tag:blogger.com,1999:blog-70789780913255128382024-02-18T21:37:08.622-05:00Let's Talk PrimatesTalking with human primates about non-human primates, ecology, and conservation.Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.comBlogger76125tag:blogger.com,1999:blog-7078978091325512838.post-56316948920449082582016-08-19T15:14:00.001-04:002016-08-19T15:14:01.681-04:00Happy World Orangutan Day- A Brief Review of Recent Research and News<div class="separator" style="clear: both; text-align: center;">
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Happy <a href="http://www.worldorangutanevents.org/" target="_blank">World Orangutan Day</a>. Orangutans, both Bornean (<i>Pongo pygmaeus</i>) and Sumatran (<i>Pongo abelli</i>), are some of my favorite primates. These orange, solitary creatures live a primary arboreal life in the country of Indonesia on the islands of Borneo and Sumatra. They are highly intelligent and one of our closest living relatives. In honor of International Orangutan Day, I thought I'd celebrate with a post on some of the latest orangutan research.<br />
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Starting off with some good news: <a href="http://advances.sciencemag.org/content/2/3/e1500789" target="_blank">there are more Sumatran orangutans than was previously thought</a>. There are possibly 8,000 more, bringing the total up to approximately 14, 600 individuals. Better methods and techniques are the main reasons behind the increase in numbers with areas previously not surveyed visited and orangutans found at elevations higher than researchers previously thought it was likely they inhabited.<br />
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<a href="http://www.iucnredlist.org/details/39780/0" target="_blank">Sumatran orangutans</a> have been classified as critically endangered since they were first listed on the IUCN Redlist. However, <a href="http://www.iucnredlist.org/details/17975/0" target="_blank">Bornean orangutans</a> were previously listed as endangered, until it was <a href="https://www.iucn.org/news/whale-sharks-winghead-sharks-and-bornean-orangutans-slide-towards-extinction" target="_blank">announced earlier this year</a> that they have slipped to critically endangered as well. Habitat loss due to palm oil and rubber plantations threaten this species as well as hunting.<br />
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Rocky, an orangutan at the Indianapolis Zoo, can <a href="http://www.natureworldnews.com/articles/25892/20160802/talking-ape-an-orangutan-named-rocky-could-mimic-human-speech.htm" target="_blank">reproduce grunting sounds made by humans</a>. He is able to mimic the pitch and tone of sounds made by humans and started mimicking at age eight. When compared to a database filled with the sounds of other orangutans, Rocky is unique. This new finding raises more questions about the development and origin of language in humans and what our last common ancestor with orangutans looked (and sounded?) like.<br />
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Another zoo-based <a href="http://link.springer.com/article/10.1007%2Fs10071-016-1015-0" target="_blank">study </a>has shown that orangutans have the ability to use past experiences to create new images in their mind about new experiences. This ability is referred to as affective forecasting. Naong, an orangutan housed at a Swedish zoo, is able to guess whether he likes a new juice flavor based on the past juices he's tasted. Originally given four flavors of juice, once Naong was familiar with these flavors, the juices were mixed together. Naong, if he observed the mixing, was able to guess whether or not he liked the mixed flavors based on his past preferences. This is yet another way humans are not as unique and different from our primate ancestors than perhaps we thought. Although anyone who has spent a significant amount of time observing these animals at a zoo or reading up on them probably won't be too surprised.<br />
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An unsettling <a href="http://link.springer.com/article/10.1007%2Fs00265-015-2053-3" target="_blank">study </a>shows how just aggressive female orangutans can be. For the first time, researchers have observed the death of a female orangutan due to the aggressive actions of other orangutans. A young, female, Bornean orangutan attacked an older female with the help of a male orangutan for over thirty minutes. The two attackers traded off, with one attacking and the other preventing the victim from escaping. The older female later died as a result of her injuries. While aggressive behavior on this scale is known in chimpanzees, this is the first time such extreme behavior has been observed in wild female orangutans.<br />
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To end on a lighter note, a <a href="http://www.ibtimes.co.uk/sumatran-great-ape-releases-jazz-single-world-orangutan-day-1576965" target="_blank">Sumatran orangutan has released his first music single</a>. Playing on the drums and piano while a zookeeper recorded, Kluet is on his way to international fame perhaps. You can purchase the single <a href="https://www.zoossa.com.au/product/give-me-a-klue/" target="_blank">here</a>. Proceeds are going towards conservation efforts.<br />
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To conserve these animals and show your support for them, consider buying sustainable palm oil, being mindful of your overall consumption and energy expenditure, and donating your time or funds to charities that support these magnificent apes, such as <a href="https://orangutan.org/" target="_blank">Orangutan Foundation International</a>, <a href="http://www.orangutans.com.au/Orangutans-Survival-Information/About-Us.aspx" target="_blank">Bornean Orangutan Survival Foundation</a>, or the <a href="http://www.centerforgreatapes.org/who-we-are/" target="_blank">Center for Great Apes</a>.<br />
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<br />Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.com0tag:blogger.com,1999:blog-7078978091325512838.post-6171709260265710252016-07-29T09:30:00.002-04:002016-07-29T09:30:39.639-04:00Lemur habitat was changing before humans even arrivedNew research from the DNA of mouse lemurs (of the genus <i>Microcebus</i>) has lead to a surprising discovery about Malagasy forests and their ancient past. Madagascar, a large island off the west coast of Africa, is made up of many forests that are presently not connected and haven't been since around the time humans reached the island. The eastern rainforests (green in the image below) are separated from the western, deciduous forests (blue in the image below) by an expanse of grasslands (in yellow). There are multiple theories concerning what the landscape looked liked in the past and why the eastern and western forests are separated, and research from Yoder and colleagues (2016) uses the genetic history of lemurs to tell us more.<br />
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Habitats of Madagascar and species locations. </div>
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From Yoder et al., 2016</div>
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Some believe that, rather than this disconnect we now see between western and eastern forests, Madagascar was covered in closed-canopy forests prior to the arrival of humans, with humans acting as the primary agents of change. This so-called forest hypothesis maintains that the large expanse of grasslands that experience frequent burning were once forests and their reduction was not natural.Others believe that the grasslands we see today are similar to ancient grasslands found in Madagascar. Thus, the landscape was not so radically different from the present. This is referred to as the grassland hypothesis by Yoder and colleagues (2016). Finally, another idea termed the mosaic hypothesis by Yoder and colleagues (2016) suggests that the central part of the country was covered with a mix of wooded savanna and closed-canopy forests.<br />
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Some of the world's top lemur experts have provided us with new information on the history of Madagascar's forests. Yoder and colleagues (2016) looked at the DNA of five different species of mouse lemurs, a genus dependent on the forest, to understand how the forests across this island nation changed. One of their research questions asks if the divide between the two forest habitats is natural or what remains of a transitional cline?<br />
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Results suggest that the five species studied started diverging from one another roughly five hundred and forty thousand years ago with the last node of divergence around fifty-five thousand years ago. The timing of mouse lemur evolution and divergence coincides with evidence suggesting great variation in climate.<br />
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<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgA5Qt9nIx5kDFEDyXlUO_BiCWJngXjglDb-2IgOtcBdHfux5IcJwRVJ9ZqU9RyS2MJmo0WRU2BupDuediJr4s8f3svn1buJ7vR-C9EVl7SPJdkBOBHRxs9Fbxu8cp1fCOgCjpkZvPAa-8/s1600/Capture.PNG" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="237" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgA5Qt9nIx5kDFEDyXlUO_BiCWJngXjglDb-2IgOtcBdHfux5IcJwRVJ9ZqU9RyS2MJmo0WRU2BupDuediJr4s8f3svn1buJ7vR-C9EVl7SPJdkBOBHRxs9Fbxu8cp1fCOgCjpkZvPAa-8/s320/Capture.PNG" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><i>M. murinus. </i>Photo:<a href="https://www.flickr.com/photos/joachim_s_mueller/473754210" target="_blank"> Joachim S. Muller</a></td></tr>
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Genetic analysis of <i>M. myoxinus, </i>a subspecies of mouse lemur that lives in continuous forests, and <i>M. lehilahytsara</i>, another subspecies that lives in a mosaic of forests, show significantly different patterns in regards to geographic patterns of divergence. Results suggest that <i>M. lehilahytsara</i>, the mouse lemur in a mosaic of forests, has lived in this type of habitat for a very long period of time, since before the arrival of humans. Thus, genetic evidence from mouse lemurs does not support the forest hypothesis.<br />
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Yoder and colleagues (2016) also discovered that <i>M. berthae </i>and <i>M. rufus </i>are more closely related than would be expected, given their geographic differences. One species lives lives in the southeast in humid forests and the other in dry forests of the west. This close genetic relationship points towards the mosaic hypothesis of Madagascar's ancient geography. We see a genetic divergence that is tens of thousands of years old and not uniform across all Microcebus species.<br />
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Thus, using the genes of mouse lemurs, Yoder and colleagues (2016) were able to conclude that the central part of Madagascar was composed of a mosaic habitat composed of forests and grasslands. The arrival of humans does not appear to have caused a tremendous change from an entirely forested landscape to grasslands similar to what we see today.<br />
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Links of possible interest:<br />
<a href="http://www.wildmadagascar.org/overview/ecosystems.html" target="_blank"><br /></a>
<a href="http://www.wildmadagascar.org/overview/ecosystems.html" target="_blank">Ecosystems in Madagascar</a><br />
Read the paper <a href="http://www.pnas.org/content/113/29/8049.full#sec-12" target="_blank">here</a><br />
<a href="http://letstalkprimates.blogspot.pe/p/say-no-to-pet-primates.html" target="_blank">They may be cute, but you shouldn't have a primate as a pet</a><br />
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<span style="font-family: inherit; font-size: x-small;">Works cited: </span><br />
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<span style="font-size: x-small;"><span style="font-family: inherit;">Blome, M. W., Cohen, A. S., Tryon, C. A., Brooks, A. S., & Russell, J. (2012). The environmental context for the origins of modern human diversity: a synthesis of regional variability in African climate 150,000–30,000 years ago. Journal of Human Evolution, 62(5), 563-592.</span></span><br />
<span style="font-family: inherit; font-size: x-small;">Cannon, C. H., Morley, R. J., & Bush, A. B. (2009). The current refugial rainforests of Sundaland are unrepresentative of their biogeographic past and highly vulnerable to disturbance. Proceedings of the National Academy of Sciences, 106(27), 11188-11193.</span><br />
<span style="font-family: inherit; font-size: x-small;">Scholz, C. A., Cohen, A. S., Johnson, T. C., King, J., Talbot, M. R., & Brown, E. T. (2011). Scientific drilling in the Great Rift Valley: the 2005 Lake Malawi Scientific Drilling Project—an overview of the past 145,000 years of climate variability in Southern Hemisphere East Africa. Palaeogeography, Palaeoclimatology, Palaeoecology, 303(1), 3-19.</span><br />
<span style="font-family: inherit; font-size: x-small;">Yoder, A. D., Campbell, C. R., Blanco, M. B., dos Reis, M., Ganzhorn, J. U., Goodman, S. M., ... & Ralison, J. M. (2016). Geogenetic patterns in mouse lemurs (genus Microcebus) reveal the ghosts of Madagascar's forests past. Proceedings of the National Academy of Sciences, 201601081.</span><br />
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Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.com3tag:blogger.com,1999:blog-7078978091325512838.post-48940722447754975042016-07-14T07:46:00.004-04:002016-07-14T07:46:28.175-04:00Viruses detected on plants chewed by primatesNew research has discovered a noninvasive way to test primates for viruses. Collaboration between UC Davis and Gorilla Doctors has shown that the plants mountain gorillas (<i>Gorilla beringei beringei</i>) and golden monkeys (<i>Cercopithecus mitis kandti</i>) consume and discard can be collected and analyzed to determine what viruses the animals have. Blood samples and oral and rectal swabs all require the researcher to anesthetize the animal, something that is not done with critically endangered mountain gorillas unless absolutely necessary.<br />
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEis2RxhSBjp47BmcCyYA3jy8qLBl1U_qkUxsZE0lmPdKsH6wI36ZTXNuBCt7zjWyJV7cfDO_lxny-UoyLuqpJwePJAcqCFU-8olNbdRl1ev1lS5w_8rnj3HC38ohbNYfD6e1K-K_2jzur8/s1600/Screen+Shot+2014-09-24+at+12.32.21+PM.png" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img border="0" height="202" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEis2RxhSBjp47BmcCyYA3jy8qLBl1U_qkUxsZE0lmPdKsH6wI36ZTXNuBCt7zjWyJV7cfDO_lxny-UoyLuqpJwePJAcqCFU-8olNbdRl1ev1lS5w_8rnj3HC38ohbNYfD6e1K-K_2jzur8/s320/Screen+Shot+2014-09-24+at+12.32.21+PM.png" width="320" /></a></div>
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Thus, this new noninvasive method will allow researchers to detect viruses simply by following the animals at a distance and collecting any bits of chewed bark, leaves, or fruit the individual discards. For this study, Smiley Evans and colleagues (2016) spent almost a year collecting these vegetation discards from 294 gorillas from 26 different family groups across the Volcanoes National Park, Bwindi Impenetrable Forest, and Mgahinga Gorilla Park.<br />
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The authors also looked at golden monkeys, collecting plant samples on three different dates in order to determine if their methods could be used on other primate species. Samples were collected from 18 individuals. For both species, researchers observed the animals, collected disregarded plant parts, and sampled from plants with visible bite marks and saliva.<br />
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It was possible to collect samples from nearly every individual in a family, including infants who may not consume the plants but still bite and chew them. DNA and RNA viruses were both successfully detected using this method with minimal disruption. Compared to other methods, Smiley Evans and colleagues were able to sample more individuals with less risk and little behavioral disruption. Using this method, the researcher easily knows the age of the sample because close behavioral observation is required.<br />
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Golden monkeys proved more challenging than mountain gorillas because they are arboreal and handle food less with their mouths when compared to mountain gorillas. However, it is still possible to collect samples, but researchers should prepare to collect fewer samples per visit.<br />
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This research is especially important for mountain gorillas because infectious diseases are one of the greatest threats to this species, and as wildlife increasingly comes into contact with humans, breakthroughs in disease ecology have the potential to positively impact these gentle giants. Roughly 60% of the remaining 880 mountain gorillas are habituated to humans (Gray et al., 2011; Robbins et al., 2011), meaning they encounter humans, whether tourists, researchers, or others, on a regular basis and are accustomed their presence.<br />
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<span style="font-family: "times new roman";">Links of possible interest: </span><br />
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<a href="http://www.iucnredlist.org/details/39999/0" target="_blank">IUCN mountain gorilla page</a></div>
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<a href="http://www.gorilladoctors.org/" target="_blank">Gorilla Doctors</a></div>
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<a href="http://letstalkprimates.blogspot.pe/2015/04/mountain-gorilla-genome-sequenced.html" target="_blank">Mountain gorilla genome sequenced</a><br />
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Works cited:<br />
Gray, M., Fawcett, K., Basabose, A., et al., (2011). Virunga Massif Mountain Gorilla Census 2010 Summary Report. International Gorilla Conservation Programme.<br />
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Robbins, M. M., Roy, J., Kato, R., Kabano, P., Basabose, A., Tibenda, E., ... & Gray, G. (2011). Bwindi Mountain Gorilla Census 2011-Summary of Results. Uganda Wildlife Authority, 28.<br />
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Smiley Evans, T., Gilardi, K. V., Barry, P. A., Dsebide, B. J., Kinani, J. F., Nizeyimana, F., ... & Mazet J. A. (2016). Detection of Viruses Using Disregarded Plants from Wild Mountain Gorillas and Golden Monkeys. <i>American Journal of Primatology</i>.<br />
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Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.com0tag:blogger.com,1999:blog-7078978091325512838.post-43923438470700234152016-06-19T08:53:00.001-04:002016-06-19T08:58:49.739-04:00Adapted for adaptability-evidence suggests primate brains use reservoir computing<div class="separator" style="clear: both; text-align: center;">
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<tr><td style="text-align: center;"><a href="https://upload.wikimedia.org/wikipedia/commons/thumb/d/de/Primate_skull_series_with_legend.png/1600px-Primate_skull_series_with_legend.png" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="235" src="https://upload.wikimedia.org/wikipedia/commons/thumb/d/de/Primate_skull_series_with_legend.png/1600px-Primate_skull_series_with_legend.png" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><a href="https://commons.wikimedia.org/wiki/File:Primate_skull_series_with_legend.png" target="_blank">Photo: Christopher Walsh, Harvard Medical School</a></td></tr>
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Primate brains are incredibly adaptive, responding to new situations and stimuli as needed. Think of all of the various skills we learn from computer programming to making pottery to neuroscience. Our brains learn new content and do so relatively efficiently, but how? How are humans and other primates so good at adapting to new information and scenarios?<br />
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Enel and colleagues (2016) wanted to better understand how our primate brains adapt to situations and stimuli that evolution could not have directly anticipated. They took advantage of developments from Rigotti and colleagues (2010) in reservoir computing, a branch of recurrent neural networks in which randomly connected neurons form a network of recurrent loops. Recurrent connections are fixed but connections from to output neurons can change. Rigotti and colleagues (2010) propose that recurrent neural networks with multiple, different neuronal responses are significant in the ability to complete complex cognitive tasks.<br />
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Enel and colleagues (2016) developed a recurrent neural network model that would perform a specific cognitive task and then compared predictions from the model to data from rhesus monkeys. Of four potential targets on a touch screen, only one would reward the monkeys with fruit juice. The monkeys needed to discover the fruit juice target by trial and error. The target corresponding to fruit juice changed after every trial.<br />
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<tr><td class="tr-caption" style="text-align: center;">Model Architecture, Figure from Enel and colleagues 2016 paper, Reservoir Computing Properties of Neural Dynamics in Prefrontal Cortex</td></tr>
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Results show that the model was able to shift when it did not receive a reward and repeat when it did, a new extension of the functions of reservoir computing. The model was able to perform the task almost perfectly using a circular search and an ordered search and when trained on a schedule that was derived from the performance of one of the monkeys. Enel and colleagues (2016) compared the neural coding behavior of the model with the primate cortex. They found that variance in the presence of reservoir neurons in 1) target choice and 2) phase of the problem (either continue searching to find the reward or repeat because the reward has been discovered) show significant effects for both choice and phase. Choice and phase could not be directly derived from current inputs, but instead needed the history of previous inputs and their responses. This has also been observed for the primate brain (Barone and Joseph, 1989). See the published paper for the full results and more details about their findings.<br />
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This new research helps to explain how primates face and then handle a diverse and endless range of situations. It will be interesting to see if the same mechanism for behavioral adaptability is found in non-primate species or if it is unique to primates.<br />
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<span style="font-size: x-small;">Works cited:</span><br />
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;">Barone, P., & Joseph, J. P. (1989). Prefrontal cortex and spatial sequencing in macaque monkey. <i>Experimental brain research</i>, 78(3), 447-464.</span><br />
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;">Enel, P., Procyk, E., Quilodran, R., & Domineer, P., F. (2016) Reservoir Computing Properties of Neural Dynamics in Prefrontal Cortex. <i>PLoS Comput Biol, </i>12(6): e1004967. DOI: 10.1371/journal.pcbi.1004967 </span><br />
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;">Rigotti, M., Ben Dayan Rubin, D. D., Wang, X. J., & Fusi, S. (2010). Internal representation of task rules by recurrent dynamics: the importance of the diversity of neural responses. <i>Frontiers in Computational Neuroscience</i>, 4, 24.</span>Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.com0tag:blogger.com,1999:blog-7078978091325512838.post-73761915606077964422016-05-25T09:13:00.000-04:002016-05-25T09:18:21.789-04:00Cercopithecus monkeys opportunistically prey on bats<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: left; margin-right: 1em;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiyg5lwoMafrvmz13ZPS7z71-5DvdQ0to4aLKcW47gOtOx3zHD6lm9xrIQYhBl5btA2RXcmcSO7xyOest8TPRFhJs6gp70nD1c3PagTttD45eyy_o9wKJBRZscVGZcfRnVMbMrdqwsKPHs/s1600/Screen+Shot+2016-05-25+at+8.27.50+AM.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="213" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiyg5lwoMafrvmz13ZPS7z71-5DvdQ0to4aLKcW47gOtOx3zHD6lm9xrIQYhBl5btA2RXcmcSO7xyOest8TPRFhJs6gp70nD1c3PagTttD45eyy_o9wKJBRZscVGZcfRnVMbMrdqwsKPHs/s320/Screen+Shot+2016-05-25+at+8.27.50+AM.png" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="font-size: 13px; text-align: center;"><i>C. mitis, </i>photo <a href="https://www.flickr.com/photos/dianasch/16100567768/in/photolist-qwKBS1-6nMAdK-62hrgY-6vZdTF-6rSUow-6r9WeL-6rUAtT-3h8bXN-pJxWNa-6HiMCY-6sSQBK-73m6kz-4Aqsnu-c9oxxd-73m7r8-5Huwrg-5HxsL3-6oN6GB-4s4WVr-7nRDZN-vroym-7s7dgZ-dM7S6x-mDym3-acxry-hbvkGW-y4tx3-8vi9nt-4jvv9C-8vGnwi-g67FRp-9c83gc-o2jQfS-6rkzM7-7u7qAH-5HB5zc-acxs3-7SFkAx-9Fb5CM-o2mgGy-5w4umv-iAjL6-bf6EYT-mgdUDZ-8kcjar-7SJBJS-3eHezR-5QkAmn-kETVi6-5T2j3H" target="_blank">Diana Robinson</a></td></tr>
</tbody></table>
Two species of Cercopithecus monkeys in Kenya have been observed and documented feeding on bats when the opportunity presents itself. Tapanes and colleagues (2016) photographed and filmed this behavior in Blue monkeys, <i>Cercopithecus mitis, </i>and in one monkey which was a hybrid species of <i>C. mitis </i>and<i> C. ascanius, </i>the Red-tailed monkey<i>. </i>They report on thirteen observations of bat predation attempts over six and a half years at two sites, Gombe in Tanzania and the Kakamega Forest in Kenya). Of these thirteen attempts, eleven were successful. Surveying researchers of blue and red-tailed monkeys at other sites did not identify further instances of bat predation.<br />
<br />
Although identifying the bats was challenging, Tapanes and colleagues determined that multiple species of bats were consumed. Researchers observed two instances where an individual grabbed a lone roosting bat and consumed it. In the other observations, the researchers did not witness the individual capturing the bat.<br />
<br />
Unsurprisingly, the evidence suggests that bats are a preferred food item for Cercopithecus monkeys. In two of a successful predation event, other monkeys gathered around and observed the monkey feeding on the bat. Three instances were observed where some sort of aggressive display or behavior to either obtain or retain the bat, implying this food item is worth fighting over.<br />
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All observed instances of this behavior occurred in either forest edges or human-modified habitat, raising the question as to whether or not this behavior occurs naturally or is a product of habitat destruction and alteration due to human activities. It is possible that anthropogenic changes to the landscape have resulted in blue and red-tailed monkeys altering their feeding patterns and behaviors accordingly, with increased consumption of bats as a potential modification. Thirty-six years of data collection at Kakamega forest show that bat predation coincides with increased use of plantation forests that has occurred due to forest fragmentation and loss. Tapanes and colleagues (2016) also suggest that bat predation could be more widespread, but it is simply easier for researchers to observe this rare behavior within altered habitats. They do not think this reason is likely, stating that observation conditions were similar in both plantation forest and forest that is more natural.<br />
<br />
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhRMtyjK5eg69bEnne3UopA1-Y7MCzFAhapElv8YZact2fFEcNHMVa9Vr-DPb8E9wSIyVQeEMNtWpYqyKsQsU_y_QyTzh1y7un79Bcqwiyvcd5jo8BhhoVeastTOzBusl8ybXzc4smkrVY/s1600/Screen+Shot+2016-05-25+at+9.04.41+AM.png" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="180" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhRMtyjK5eg69bEnne3UopA1-Y7MCzFAhapElv8YZact2fFEcNHMVa9Vr-DPb8E9wSIyVQeEMNtWpYqyKsQsU_y_QyTzh1y7un79Bcqwiyvcd5jo8BhhoVeastTOzBusl8ybXzc4smkrVY/s320/Screen+Shot+2016-05-25+at+9.04.41+AM.png" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="font-size: 13px; text-align: center;">Blue monkey feeding, photo <a href="https://www.flickr.com/photos/christoph_straessler/16847132867/in/photolist-ajYKS8-5KfcSA-atwXK9-rEHXE4-7ed42p-dX18ym-6ZQ7x7-RYk19-5Y12vc-nWhkad-arQcXa-7ed3Yr-5Hru2A-eKVbpX-7Lq6HJ-aHGkQe-4NXMYP-7egWqj-7ed7jn-2xsSic-9yKNHV-py4ctK-6KyW4E-iRDcxG-984pX5-7egZx5-j4B3q5-2WZxy4-5GGCGG-3Rz7WB-353Zvo-bbZjkB-7mWd7Q-3p3Bcz-44D8GC-5zAEMU-5338sY-9P7ZDp-nWUsHK-gYHpke-bwt4ZM-apMtAK-4RaSd8-574vet-vDzFz-k42kbP-7UMXRa-9nKgk9-6Q972C-aFc4FU" target="_blank">Christoph Strässler</a></td></tr>
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These findings have important implications for the transmission of <b>zoonotic diseases</b>, or diseases that can be transmitted from animals to humans. It has previously been hypothesized that primates contract diseases from bats when they consume fruit with an infected bat's saliva or feces (Dobson, 2005; Alexander et al., 2015; Rodhain, 2015). This latest study forces us to consider the fact that directly handling the bats themselves may be a method for disease transfer. As monkeys can transmit many diseases to humans, it is worth studying this phenomenon more, if possible.<br />
<br />
Links of potential interest:<br />
<a href="http://www.iucnredlist.org/details/4221/0" target="_blank">IUCN Redlist page for C. mitis</a><br />
<a href="http://netvet.wustl.edu/species/primates/primzoon.txt" target="_blank">Primate zoonotic diseases</a><br />
<a href="http://www.smithsonianmag.com/science-nature/which-primate-is-the-most-likely-source-of-the-next-pandemic-38535377/?no-ist" target="_blank">Which primate is likely the source of the next pandemic?</a><br />
<a href="http://letstalkprimates.blogspot.com/2014/11/connections-between-ebola-primates-and.html" target="_blank">Ebola, primates, and bushmeat</a><br />
<br />
<span style="font-size: x-small;">Works cited:</span><br />
<span style="font-size: x-small;">Alexander, K. A., Sanderson, C. E., Marathe, M., Lewis, B. L., Rivers, C. M., Shaman, J., ... & Eubank, S. (2015). What factors might have led to the emergence of Ebola in West Africa?. <i>PLoS Negl Trop Dis</i>, 9(6), e0003652.</span><br />
<span style="font-size: x-small;">Dobson, A. P. (2005). What links bats to emerging infectious diseases?. <i>Science</i>, 310(5748), 628-629.</span><br />
<span style="font-size: x-small;">Rodhain, F. (2015). Chauves-souris et virus: des relations complexes. <i>Bulletin de la Société de pathologie exotiqu</i>e, 108(4), 272-289.</span><br />
<span style="font-size: x-small;">Tapanes, E., Detwiler, K. M., & Cords, M. (2016). Bat Predation by Cercopithecus Monkeys: Implications for Zoonotic Disease Transmission. <i>EcoHealth</i>, 1-5.</span><br />
<br />Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.com0tag:blogger.com,1999:blog-7078978091325512838.post-11692758334145968732016-04-19T07:22:00.002-04:002016-04-19T07:22:14.684-04:00What do geladas and humans have in common? Apparently, vocal patterns.<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjp3-cjIarEJA5eAlWd3Hr_mCsZcATTQF99WJDuuskJB7lC2lMUpn3_ECN4OZEBOCSt-2BxoDv0qTAWW3-06NpimUPJzE4dsjOmBlEyuAKs4TspTnRHZajEnUDxpn2BsLIICeH9ZOqEqC8/s1600/Screen+Shot+2016-04-18+at+7.53.15+PM.png" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="206" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjp3-cjIarEJA5eAlWd3Hr_mCsZcATTQF99WJDuuskJB7lC2lMUpn3_ECN4OZEBOCSt-2BxoDv0qTAWW3-06NpimUPJzE4dsjOmBlEyuAKs4TspTnRHZajEnUDxpn2BsLIICeH9ZOqEqC8/s320/Screen+Shot+2016-04-18+at+7.53.15+PM.png" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><i style="text-align: start;">T. gelada. </i><span style="text-align: start;">Photo: <a href="https://www.flickr.com/photos/rod_waddington/8199829450/in/photolist-duAgBQ-duuwyV-aqgQ49-mfud7D-cxmGAq-5Br98a-7F7GqJ-qngbDJ-bgzbcn-mfS5eG-kP51NL-bDq9cz-gS7sYH-pCej6u-5zrnrN-8RrMdD-5SWsP6-8Pr8iU-7mFczT-ft6ERJ-sJVCg-pCHbYx-rwpJe4-tuBSaa-td1VSu-8WaKnH-8wMhpF-8eWEBm-8WaKaV-pTkqqE-pM3obV-jFFxJG-tUHNu-yZ6ig-pqtzLo-qxTqJ8-pTkpkU-8WhnAb-5Gr4PE-qxLbdC-55cHkZ-89Nxnr-9ySUxf-aNioYg-hovs1z-9UjfkF-tUHND-tUHNB-qxURNx-8WdMzJ" target="_blank">Ron Waddington</a></span></td></tr>
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They live in very large groups called herds, they primarily graze on terrestrial vegetation, and they roam on large open plains. In more than a few ways, geladas (<i>Theropithecus gelada</i>) are similar to cows. Geladas are more vocal than cows though. They have a diverse range of vocalizations for various behaviors and situations, such as contact, showing submission, aggression, and others (Kawai, 1979; Aich et al., 1990). The diversity and complex communication exhibited by geladas is one of the reasons this is a very interesting primate species to study.<br />
<br />
A new study on their vocal sequences shows that this species of <b>Old World Monkey</b> follows patterns that are similar to humans. As far back as the late eighties, Richman (1987) suggested the geladas use melody and rhythm in ways similar to humans. Now, Gustison and colleagues have shown that the longer the sequence of sounds is that a gelada makes, the shorter the sounds within that long sequence. This is the same pattern observed in humans and is called Menzerath's law. The longer our sentences, the shorter the words tend to be in those sentences. <br />
<br />
The authors studied fifty-seven male geladas in the wild and recorded and analyzed over 1000 vocal sequences. In addition to discovering that longer sequences are made up of shorter calls, Gustison and colleagues report that long sequences start with short calls and short sequences start with long calls. Thus, the start of the sequence is an indicator of its overall length. Longer sequences also have faster tempos. Gustison and colleagues state this might be to reduce the possibility of one gelada being "talked over" by another. You can understand how this might be a problem in a chatty species that lives on open plains. If you have a lot to say, you better say it quickly.<br />
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<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: left; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjeZfcpm217gPfBvf5u3VOf27D-hxO0mNKiaMMl4IH-Y38NT9jaAdYKB7-u24Iot9djG2jfjp-3Dxg35Vah7TUKv1cAbp6gfPnSRJeNNdIsc5NJ4K4JAQNE71OLfheHz-vNPO-xeOkxTPg/s1600/Screen+Shot+2016-04-18+at+7.49.25+PM.png" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="240" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjeZfcpm217gPfBvf5u3VOf27D-hxO0mNKiaMMl4IH-Y38NT9jaAdYKB7-u24Iot9djG2jfjp-3Dxg35Vah7TUKv1cAbp6gfPnSRJeNNdIsc5NJ4K4JAQNE71OLfheHz-vNPO-xeOkxTPg/s320/Screen+Shot+2016-04-18+at+7.49.25+PM.png" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Geladas grazing. Photo <a href="https://www.flickr.com/photos/merula/5343928380/in/photolist-99e2Jd-68o1BQ-59EgP2-9chwst-932Uyn-hovTiQ-oCrHsd-7MfjGP-fsRjPV-8Mp7Fo-4JhaEk-jaNDKJ-4JmoMQ-qxM6nq-ar2i1n-4JhagB-7RCXs-4JmnDG-4JhabK-9ZaErA-4Jhaei-s9fMMZ-neTHPs-ft6F9q-6EGJYc-fsRjLM-egh4QJ-fsRjUa-afE6zh-68o1Jd-6Dkfew-ft6EPY-ft6EZb-79q9o1-8GzH6-5Zo7kT-ft6F1Y-fsRjDK-ft6FcU-68o1FE-9ekNtS-7YKPew-5tZZzf-7kRd2d-8wK8Eu-Los8S-ft6FbA-rFDsnc-4ReM7u-qQpsBY" target="_blank">Alastair Rae</a></td></tr>
</tbody></table>
Interestingly, there was no negative relationship between the position of a call and its duration (calls later in the sequence were not shorter). Yet, the proportion of grunts where the gelada was exhaling decreased in longer sequences and the proportion of grunts where the individual inhaled increased. The authors believe this pattern is due to the fact that individuals make grunts with both inhalations and exhalations on the same breath as the sequence lengthens. Once geladas have more than 15 calls per sequence, the majority of their calls have both inhale and exhale grunts and the proportion of inhale and exhale grunts hardly varies. Thus, respiration and energy demands may constrain gelada vocalizations, and be partially the reason for conforming with Menzerath's law.<br />
<br />
This is the first time Menzerath's law has been studied in non-humans. Thus, other animals with expansive vocal repertories, such as songbirds, may also exhibit this law. It is hard to draw conclusions about the evolution of communication in non-human primates and our human ancestors without knowing if Menzerath's law holds true for species that are further separated from humans. For now, we know humans are not unique in adhering to Menzerath's law. It is possible that this pattern existed before meaningful combinations of vocalizations had evolved. Tests in other species will only serve to improve our understanding of sequences, vocal patterns, and the evolution of language and communication in general.<br />
<br />
<br />
<br />
Links of potential interest:<br />
<a href="https://en.wikipedia.org/wiki/Menzerath%27s_law" target="_blank">Menzerath's Law</a><br />
<a href="http://www.iucnredlist.org/details/21744/0" target="_blank">IUCN page on geladas</a><br />
<a href="https://www.youtube.com/watch?v=WNYP6ypx9mE" target="_blank">YouTube video on gelada chatter</a><br />
<br />
Works cited:<br />
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;">Aich, H., Moos-Heilen, R., & Zimmermann, E. (1990). Vocalizations of adult gelada baboons (<i>Theropithecus gelada</i>): acoustic structure and behavioural context. <i>Folia primatologica</i>, 55(3-4), 109-132.</span><br />
<span style="font-size: x-small;">Kawai, M. (1979). Auditory communication and social relations. <i>Ecological and Sociological Studies of Gelada Baboons</i>, 219-241.</span><br />
<span style="font-size: x-small;">Gustison, M., Semple, S., Ferrer-I-Rancho, R, Bergmann, T. (in press). Gelada vocal sequences follow Menzerath’s linguistic law. PNAS. www.pnas.org/cgi/doi/10.1073/pnas.1522072113 </span><br />
<span style="font-size: x-small;">Richman, B. (1987). Rhythm and melody in gelada vocal exchanges. <i>Primates</i>, 28(2), 199-223.</span>Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.com0tag:blogger.com,1999:blog-7078978091325512838.post-76681725795514206152016-04-15T06:50:00.000-04:002016-04-15T06:50:02.760-04:00What you may not have read about the scary decline in Grauer's Gorilla numbers<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: left; margin-right: 1em; text-align: left;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj9I7KH3ID5ZP3NOSs9aMTQtCOfJVCFx1XdbhmXuEa_fu2Qd5qhqFJ7EOUopFFor2XBZ_bCUZXTNBZuOsNKdhmrS9t_AgtO7Bi0QHrf77e-j6Ud_Vm6HOrWQm80rVBPL55ihsVoim6qmto/s1600/Screen+Shot+2016-04-14+at+7.33.06+AM.png" imageanchor="1" style="clear: left; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj9I7KH3ID5ZP3NOSs9aMTQtCOfJVCFx1XdbhmXuEa_fu2Qd5qhqFJ7EOUopFFor2XBZ_bCUZXTNBZuOsNKdhmrS9t_AgtO7Bi0QHrf77e-j6Ud_Vm6HOrWQm80rVBPL55ihsVoim6qmto/s320/Screen+Shot+2016-04-14+at+7.33.06+AM.png" width="226" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Cover of the WCS and FFI Report</td></tr>
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Over a week ago, a report from Wildlife Conservation Society and Fauna and Flora International hit the press about Grauer's gorillas (<i>Gorilla beringei graueri). </i>Grauer's gorillas, previously known as eastern lowland gorillas, are one of four subspecies of gorillas. Consuming fruits and vegetation, Grauer's gorillas are the largest subspecies. They are listed as endangered and are found only in the Democratic Republic of Congo (DRC).<br />
<br />
They made the headlines, and not just on the science news sources, because the latest data shows their numbers have declined dramatically. Over the past twenty years, Grauer's gorilla numbers have declined by an astonishing 77%, with only 2, 585 animals estimated alive today. Their range has been reduced by 84-93%. If you saw this on the news, you probably also saw that civil unrest and other human pressures are the reasons behind the sudden decline. This is hardly surprising.<br />
<br />
What you may have missed are some of the more nuanced details behind these numbers, details that can be found in the report itself, which also covers chimpanzees in the same area. In their report titled, "Status of Grauer's Gorilla and Chimpanzees in Eastern Democratic Republic of Congo: Historical and Current Distribution and Abundance," we learn that increases in agriculture and the availability and use of shot guns caused habitat loss and extinctions of local populations in the 60s and 70s. Surveys done in the 90s also suggested species decline due to expanding human populations and hunting. The late 90s and early 2000s saw these threats exacerbated when refugees from civil war in Rwanda, internally displaced people, and armed groups in the DRC put further pressure on DRC forests and wildlife. This influx of people needed fuel for firewood, land for agriculture, timber, and also hunted wildlife and mined.<br />
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The main threats to Grauer's gorillas are hunting for bushmeat and habitat loss due to the spread of agriculture. Hunting practices are related to artisanal mining though. These mines are found adjacent to or even in protected areas, are illegal, and are controlled by armed militias (Kirkby et al., 2015). They allow people an economic opportunity to earn an income quickly and attract people from multiple social classes(Kirkby et al., 2015). Once working at these remote mines, miners rely on bushmeat for food and consume primates and other large mammals(Kirkby et al., 2015). The miners aren't evil people though, as many said they wouldn't hunt bushmeat if alternatives were available and also said they wanted to leave the mining industry.<br />
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<a href="http://letstalkprimates.blogspot.com/2014/08/smart-wildlife-conservation-tool.html" target="_blank">SMART</a> patrols, reconnaissance surveys, transects, and occupancy surveys were used to determine gorilla decline and show that one of the areas with the highest number of animals, Kahuzi-Biega National Park saw a decline of 87% in gorilla density, and this is with a portion of the Park protected reasonably well. Seven of the eleven sites surveyed through encounter rates show an average decline of 94%. These findings are enough to support raising the IUCN status of Grauer's gorillas to critically endangered.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi4KbME6UIgrq-5NwuYdov49JUd4IzJbsb6_qDS5ey5-rZ49PP94tyQEDJleHM-FOcMoSHRnReeiqTb0hi3YzbYwgK6tHI9kUb4GxOk3PFm7EPqdvISFzRilmcQkot3qMnYgLOLu-clThI/s1600/Screen+Shot+2016-04-15+at+6.32.38+AM.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="400" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi4KbME6UIgrq-5NwuYdov49JUd4IzJbsb6_qDS5ey5-rZ49PP94tyQEDJleHM-FOcMoSHRnReeiqTb0hi3YzbYwgK6tHI9kUb4GxOk3PFm7EPqdvISFzRilmcQkot3qMnYgLOLu-clThI/s400/Screen+Shot+2016-04-15+at+6.32.38+AM.png" width="282" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Occupancy probability model from report. Blue areas <br />mean high likelihood and red very low likelihood of gorillas</td></tr>
</tbody></table>
<div class="separator" style="clear: both; text-align: center;">
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Behind these alarming numbers, a story emerges of people pushed beyond their limits and forced to use the forests available in order to survive. Civil war, changes in government, and general civil unrest gives the DRC its tumultuous historic timeline, the effects of which not only impact people but also the flora and fauna of the region. Some may find it easy to forget, but humans and nature are intricately linked.<br />
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You may think you have no connection to this story other than one as an innocent bystander, but the resources mined from the DRC are part of an industry many of us play into. Most of the mines are for cassiterite, gold, coltan, and wolframite. The first is an important source of tin, the second you may be wearing now, coltan is used in electronics such as our cell phones, and the last is an important source of <a href="http://www.itia.info/tungsten-primary-uses.html" target="_blank">tungsten</a>. Given that mining is one of the main reasons Grauer's gorillas are threatened, chances are many of us are connected to this problem, as uncomfortable as that may make us feel.<br />
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Links of potential interest<br />
<a href="http://www.iucnredlist.org/details/39995/0" target="_blank">IUCN Page for Grauer's Gorillas</a><br />
<a href="http://www.iucnredlist.org/technical-documents/categories-and-criteria/2001-categories-criteria#categories">IUCN Categories and Their Criteria</a><br />
<a href="http://www.bbc.com/news/world-africa-13283212" target="_blank">BBC's Country Profile of the DRC</a><br />
<br />
<span style="font-size: x-small;">Works cited:</span><br />
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;">Kirkby, A., Spira, C., Bahati, B., Twendilonge, A., Kujirakwinja, D., Plumptre, A., ... & Nishuli, R. (2015). Investigating artisanal mining and bushmeat around protected areas. Unpublished report to USAID and Arcus Foundation.</span><br />
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;">Plumptre, A.J., Nixon, S., Critchlow, R., Vieilledent, G., Nishuli, R., Kirkby, </span><span style="font-size: x-small;">A., Williamson, E.A., Hall, J.S. & Kujirakwinja, D. (2015). Status of Grauer’s gorilla </span><span style="font-size: x-small;">and chimpanzees in eastern Democratic Republic of Congo: Historical and current </span><span style="font-size: x-small;">distribution and abundance. Unpublished report to Arcus Foundation, USAID and US </span><span style="font-size: x-small;">Fish and Wildlife Service.</span>Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.com0tag:blogger.com,1999:blog-7078978091325512838.post-76928828522584731212016-04-05T07:24:00.000-04:002016-04-05T07:24:22.103-04:00Bonobos focus on the positives: humans focus on the negatives<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: left; text-align: left;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh83CiSi-tY0SDiSoBKkZ1GQ-oOC4k62zs9693iNAN_kuC-4aekgQYfRRx1ZskzCzVAh49WEnwTyTqZeoYichF_5sp4AHatijyFZoOC7HUBpqjNF9KXisY5JUC-XQEQTRoRdyNJRfEf2_0/s1600/Screen+Shot+2016-04-05+at+7.01.20+AM.png" imageanchor="1" style="clear: left; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh83CiSi-tY0SDiSoBKkZ1GQ-oOC4k62zs9693iNAN_kuC-4aekgQYfRRx1ZskzCzVAh49WEnwTyTqZeoYichF_5sp4AHatijyFZoOC7HUBpqjNF9KXisY5JUC-XQEQTRoRdyNJRfEf2_0/s320/Screen+Shot+2016-04-05+at+7.01.20+AM.png" width="212" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Photo: <a href="https://www.flickr.com/photos/wcdumonts/8943602857/in/photolist-eCjixg-7mTVfF-nQtSA6-gWzS5y-9giitr-9gipd8-7ZbC1p-2GLUny-9gmsTj-9gijyP-bDZhg-7c1ix6-dkh7TD-qRP7u-797jpJ-7ZbCce-dkh8fG-7ZbBot-dkh8XL-9x5two-5v2Svp-9gmoA9-9gingc-9uaCxv-6dA3Na-9gmsqo-9gioHK-6dsfzq-9gmqTu-9gik9M-4Puhfs-PYPz1-9oE2Nw-5JUDVi-7ZbBfi-azWXSB-e5jHkC-2GGoRc-6ds9Nu-8Qighp-5v7e2w-h2oycv-d5VRWj-gabNc9-q4BdUk-8QmnoN-6To5oB-8QifYn-9udDoU-9udFWQ" target="_blank">Mark Dumont</a></td></tr>
</tbody></table>
A recent study done on captive bonobos (<i>Pan paniscus</i>) reports that these apes focus on images that are of a more positive nature (compared to images of danger or aggression). Using a test designed to understand attentional bias in humans, researchers from various institutions in The Netherlands studied attentional bias in bonobos, our close relatives.<br />
<br />
Four female bonobos each completed either twenty-five or twenty-six trials in total over thirteen separate testing sessions. They were briefly shown two images and then a dot appeared on the screen which remained there until the individual tapped the dot. Upon tapping the dot, the individual is rewarded with a food item. In half of the trials, the images briefly shown were of a bonobo in some sort of emotional state, such as pant hooting, playing, or in distress. In the other half, the images were of a bonobo in a neutral state.<br />
<br />
By looking at the reaction time, Kret and colleagues (2016) were able to determine that bonobos are more captivated by images of other bonobos that are affiliative or protective rather than images with bonobos in distress or aggression, which has found to be the case most often for humans (Vuilleumier and Schwartz, 2001; Williams et al., 2004; Tamietto et al., 2005; Flaisch et al., 2009).<br />
<br />
Images of yawning, grooming, and sexual behavior caught the bonobo's attention the most. Reaction time was longest for yawning, followed by grooming and then sexual behaviors. Yawning is a contagious behavior in humans and also for bonobos (Palagi et al., 2014). Grooming and sexual behavior are both types of behavior that reduce tension (Manson et al., 1997; De Waal, 1997; Crockford et al., 2013).<br />
<br />
The increased attention devoted to these social behaviors suggest that they are of greater importance to bonobos than aggressive behaviors or actions associated with a threat. Given that this isn't the case with humans and what captures our attention, this study highlights another intriguing difference between the two species.<br />
<br />
Links of potential interest:<br />
<a href="http://www.pnas.org/content/early/2016/03/08/1522060113.full" target="_blank">Paper in PNAS </a><br />
<a href="http://letstalkprimates.blogspot.com/2015/01/are-famous-sex-loving-bonobos-really.html" target="_blank">Are bonobos more peaceful than chimpanzees?</a><br />
<a href="http://www.iucnredlist.org/details/15932/0" target="_blank">IUCN page on bonobos</a><br />
<br />
<br />
<span style="font-size: x-small;">Works cited:</span><br />
<span style="font-size: x-small;">Crockford, C., Wittig, R. M., Langergraber, K., Ziegler, T. E., Zuberbühler, K., & Deschner, T. (2013). Urinary oxytocin and social bonding in related and unrelated wild chimpanzees. Proceedings of the Royal Society of London B: Biological Sciences, 280(1755), 20122765.</span><br />
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;">De Waal, F. B. (1997). The chimpanzee's service economy: food for grooming. Evolution and Human Behavior, 18(6), 375-386.</span><br />
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;">Flaisch, T., Schupp, H. T., Renner, B., & Junghöfer, M. (2009). Neural systems of visual attention responding to emotional gestures. Neuroimage, 45(4), 1339-1346.</span><br />
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;">Kret, M. E., Jaasma, L., Bionda, T., & Wijnen, J. G. (2016). Bonobos (Pan paniscus) show an attentional bias toward conspecifics’ emotions. Proceedings of the National Academy of Sciences, 201522060.</span><br />
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;">Manson, J. H., Perry, S., & Parish, A. R. (1997). Nonconceptive sexual behavior in bonobos and capuchins. International Journal of Primatology, 18(5), 767-786.</span><br />
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;">Palagi, E., Norscia, I., & Demuru, E. (2014). Yawn contagion in humans and bonobos: emotional affinity matters more than species. PeerJ, 2, e519.</span><br />
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;">Tamietto, M., Latini Corazzini, L., Pia, L., Zettin, M., Gionco, M., & Geminiani, G. (2005). Effects of emotional face cueing on line bisection in neglect: a single case study. Neurocase, 11(6), 399-404.</span><br />
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;">Vuilleumier, P., & Schwartz, S. (2001). Emotional facial expressions capture attention. Neurology, 56(2), 153-158.</span><br />
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;">Williams, M. A., & Mattingley, J. B. (2004). Unconscious perception of non-threatening facial emotion in parietal extinction. Experimental Brain Research, 154(4), 403-406.</span>Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.com0tag:blogger.com,1999:blog-7078978091325512838.post-20605393863200486042016-03-23T06:48:00.003-04:002016-03-23T06:48:24.067-04:00The latest puzzling chimpanzee behavior<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; margin-left: 1em; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEihUOWurIbA7W40hmOSnNTC2BoSfZTQqyfoDAMqDJuewchgSq4VgTs5T78KMsMpEzru5kSjxmYrgqB8VjAU_cmoAstW3aoarF7-uw3tG8iGbwxH2FR8jJETcyLqNRq-kEhNTEDqcohW_ww/s1600/Screen+Shot+2014-12-11+at+12.19.12+PM.png" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="224" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEihUOWurIbA7W40hmOSnNTC2BoSfZTQqyfoDAMqDJuewchgSq4VgTs5T78KMsMpEzru5kSjxmYrgqB8VjAU_cmoAstW3aoarF7-uw3tG8iGbwxH2FR8jJETcyLqNRq-kEhNTEDqcohW_ww/s320/Screen+Shot+2014-12-11+at+12.19.12+PM.png" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Young chimpanzee. Photo credit <a href="https://www.flickr.com/photos/frauschnatterliese/14146037805/in/photolist-5nPL6-29zXHS-nmDhUW-kFBqi6-3akF4o-pteuBN-9jNQFG-8zMmft-bBR2cs-nQFwSQ-4AetBE-eh2z87-eiu8VH-5YzifQ-7iPDu4-oJfoy2-6tyzJw-aEsaCb-8oWuSc-bCBPgJ-F6XDW-3bm8iT-oNV1W3-izL1zF-os2GPu-ghYNFS-8UuGVA-nnnKhn-4x3fEk-8RyG4Y-arq7n5-oYmXpf-8zQud9-ghZb4w-6MbXGm-fGFd9m-bUmKZ9-6Mc5HE-5p37Y7-4x7geQ-8oZF1j-g6Eimo-7dhFR4-6vD1wG-adxHvw-4QnzEt-8PxP51-7ofHNA-dy9Ao2-ny39cx" target="_blank">Sabine Bresse</a></td></tr>
</tbody></table>
Of the animal kingdom, chimpanzees, <i>Pan troglodytes,</i> are one of the well-known tool users. All populations of wild chimpanzees studied have been observed using leaves to obtain food and some populations have been observed modifying branches to forage for termites and even fashioning spears to hunt bushbabies (Shumaker et al, 2011; Boesch, 2012).<br />
<br />
As is the case with studying many primates, our knowledge of tool use and how it is passed from generation to generation is limited by the number of field sites where long-term research occurs. Chimpanzees must first become used to human presence (or habituated) before their natural behavior can be studied, and this can take a great deal of time.<br />
<br />
Theorizing that the repertoire of chimpanzee behavior is much wider than what is currently known, Kühl and colleagues used camera traps to study multiple populations of chimpanzees in West Africa that are not habituated. This is when they noticed some very interesting behavior. Researchers first noted unusual piles of rocks in trees and used camera traps to determine what was behind this puzzle. They observed chimpanzees picking up rocks from piles around or in trees and then throwing them at the tree. <br />
<br />
Through the camera trap footage, researchers were able to determine that chimpanzees would throw the stones at the trees and vocalize a long-distance pant-hoot at the same time. The stones are mainly thrown by adult males and they seem to be independent of any sort of foraging behavior. The same chimpanzee was often observed returning to the tree and engaging in the behavior. This strange accumulative stone-throwing has only observed in West Africa and was seen in four populations of chimpanzees.<br />
<br />
Stone throwing may be a type of male display,
during which the individual attempts to draw attention to one's strength and impress other chimps. Kühl and colleagues theorize that using the stones in this manner may produce a loud sound resulting in a greater display. Another theory the authors present is that this may be a symbolic behavior. In either case, obviously more data is needed. Stone-throwing chimpanzees raises more questions than it does answers in terms of behavior and possibly cognition in the case of the latter theory.<br />
<br />
This work goes to show that you can still learn a great deal about a comparatively well-studied primate species even if you're not Jane Goodall and haven't been working at the same research site for decades. Kühl and colleagues have captured some truly fascinating behavior that raise a series of new questions using technology to their benefit.<br />
<br />
Links of potential interest:<br />
<a href="http://phys.org/news/2016-02-chimpanzees-stones-trees.html" target="_blank">Video of behavior</a><br />
<a href="http://panafrican.eva.mpg.de/" target="_blank">Pan African Programme: The Cultured Chimpanzee</a> <br />
<a href="http://letstalkprimates.blogspot.com/2014/12/how-human-are-chimps-differences-and.html" target="_blank">How human are chimps?</a><br />
<a href="http://letstalkprimates.blogspot.com/2015/04/female-chimps-are-more-likely-than.html" target="_blank">Females more likely to use tools when hunting </a><br />
<br />
<br />
<br />
<span style="font-size: x-small;">Works cited:</span><br />
<br />
<span style="font-size: x-small;"><span itemprop="author" itemscope="" itemtype="http://schema.org/Person"><span itemprop="name">Boesch, C.</span></span> <i>Wild Cultures: A Comparison between Chimpanzee and Human Cultures</i>. (Cambridge University Press, 2012).</span><br />
<br />
<span style="font-size: x-small;">Kühl, H. S. <i>et al.</i> Chimpanzee accumulative stone throwing. <i>Sci. Rep.</i> <b>6</b>, 22219; doi: 10.1038/srep22219 (2016). </span><br />
<br />
<span style="font-size: x-small;"><span itemprop="author" itemscope="" itemtype="http://schema.org/Person"><span itemprop="name">Shumaker, R. W.</span></span>, <span itemprop="author" itemscope="" itemtype="http://schema.org/Person"><span itemprop="name">Walkup, K. R.</span></span> & <span itemprop="author" itemscope="" itemtype="http://schema.org/Person"><span itemprop="name">Beck, B. B.</span></span> <i>Animal Tool Behavior: The Use and Manufacture of Tools by Animals</i>. (JHU Press, 2011).</span> Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.com0tag:blogger.com,1999:blog-7078978091325512838.post-45310189599828694762016-02-26T07:34:00.001-05:002016-02-26T07:34:30.866-05:00What effect temporally and spatially complex fruits may have on chimp cognition<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; margin-left: 1em; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjead09ZqROL1mgctw_-j3T9UqaNhgsik9oxcnXx3bYQiLrk4IRBqhbPRSNuZb7N4wRzfkjCY7-ESLTZjF1Lh1H7E5k3i-SlQI9RwcKUB7yULPwUI5-_kYvI37KsDogeuCZzlo7pre5ZZE/s1600/Screen+Shot+2014-12-11+at+12.21.25+PM.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="209" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjead09ZqROL1mgctw_-j3T9UqaNhgsik9oxcnXx3bYQiLrk4IRBqhbPRSNuZb7N4wRzfkjCY7-ESLTZjF1Lh1H7E5k3i-SlQI9RwcKUB7yULPwUI5-_kYvI37KsDogeuCZzlo7pre5ZZE/s320/Screen+Shot+2014-12-11+at+12.21.25+PM.png" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Photo credit <a href="https://www.flickr.com/photos/smorchon/2321103614/in/photolist-5nPL6-29zXHS-nmDhUW-kFBqi6-3akF4o-pteuBN-9jNQFG-8zMmft-bBR2cs-nQFwSQ-4AetBE-eh2z87-eiu8VH-5YzifQ-7iPDu4-oJfoy2-6tyzJw-aEsaCb-8oWuSc-bCBPgJ-F6XDW-3bm8iT-oNV1W3-izL1zF-os2GPu-ghYNFS-8UuGVA-nnnKhn-4x3fEk-8RyG4Y-arq7n5-oYmXpf-8zQud9-ghZb4w-6MbXGm-fGFd9m-bUmKZ9-6Mc5HE-5p37Y7-4x7geQ-8oZF1j-g6Eimo-7dhFR4-6vD1wG-adxHvw-4QnzEt-8PxP51-7ofHNA-dy9Ao2-ny39cx/" target="_blank">Sergio Morchon</a></td></tr>
</tbody></table>
<span class="current-selection">A recent study by </span>Janmaat and colleagues (2016) details how fruits in chimpanzee habitat are spatially and temporally complex (see that post <a href="http://letstalkprimates.blogspot.com/2016/02/the-spatial-and-temporal-complexity-of.html" target="_blank">here</a>). As Janmaat and colleagues stated, this complexity in diet has implications for chimpanzee intelligence. <br />
<br />
<span class="current-selection">Fruits are a preferred food. It's worth hunting down these high-energy food items. That said, fruits aren't always easy to find. </span><span class="current-selection"><span class="current-selection">It's a waste of energy to travel to a
specific fruiting tree with the thought of consuming a high-energy meal
if that tree isn't producing. </span>Wasting energy wandering around a forest looking for fruits that don't exist definitely isn't adaptive, and it's not something we would expect to see in chimpanzees or in any other species. It's in a chimpanzee's best interest to know where a fruit tree is and whether or not it will be fruiting. </span><span class="current-selection"><span class="current-selection">This type of processing takes a certain amount of knowledge and brain power. </span></span><br />
<br />
<span class="current-selection"><span class="current-selection">The <b>ecological intelligence hypothesis</b>
suggests that primates consuming foods that are fleeting in their
availability and scattered geographically would require larger ranges
and the cognitive capability to forage optimally for those ephemeral and
scattered foods (Milton and May, 1976; Milton, 1980; </span></span>Milton, 1981; Milton, 1988). Being able to remember where these scattered foods are and when they are available would be advantageous for the primate.<br />
<br />
<span class="current-selection">Janmaat and colleagues (2016) found </span>substantial variation between fruiting species in regards to the timing of fruit production, and the authors suggest
that chimps would benefit from learning species-specific fruiting
patterns to locate these foods. There was also
significant variation within a species in the monthly percentage of
fruiting trees across years and between forests. Rather than this knowledge being genetic or something all chimpanzees are born with, it is more likely that chimpanzees learn about synchronicity of fruiting.<br />
<br />
In regards to remembering trees that produce
large amounts of fruit, the authors used existing literature and their
own observations of great variation in fruit tree production histories
to hypothesize that chimpanzees use their ranging patterns to monitor
trees that are likely to produce large crops of fruit. Chimps would need
to store information on fruit production histories over many years,
particularly for species that fruit every few years rather than every
few months, providing further evidence of how chimpanzees use their brains and intelligence to survive in their environment.<br />
<br />
The forests chimpanzees inhabit clearly provide challenges for our closest relatives in terms of finding their preferred foods, ripe fruits. However, these intelligent animals have the brain power needed to master this environment and the challenges forests present. Their intelligence not only helps them navigate living in a social group and managing complex relationships but it also allows them to navigate the complex ecology surrounding them.<br />
<br />
Links of possible interest:<br />
<a href="http://phys.org/news/2013-10-long-term-memory-chimpanzees-food.html#nRlv" target="_blank">Chimpanzees and long term memory</a><br />
<a href="http://www.pbs.org/wgbh/nova/nature/ape-genius.html" target="_blank">NOVA's Ape Genius</a><br />
<br />
<br />
Works cited:<br />
<br />
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;">Milton, K., & May, M. L. (1976). Body weight, diet and home range area in primates. <i>Nature</i>, <i>259</i>(5543), 459-462.</span></div>
<div class="gs_citr" id="gs_cit1" tabindex="0">
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;">Milton, K. (1980). <i>The foraging strategy of howler monkeys: a study in primate economics</i>. Columbia University Press.</span></div>
</div>
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;">Milton, K. (1981). Distribution patterns of tropical plant foods as an evolutionary stimulus to primate mental development. <i>American Anthropologist</i>, <i>83</i>(3), 534-548.</span></div>
<span style="font-size: x-small;">Milton
K. 1988. Foraging behaviour and the evolution of primate intelligence.
In: Byrne RW, Whiten A, editors. Machiavellian intelligence: social
expertise and the evolution of intellect in monkeys, apes and humans.
Oxford: Clarendon Press. p 285–305.</span>Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.com0tag:blogger.com,1999:blog-7078978091325512838.post-90772338773737381932016-02-16T06:50:00.000-05:002016-02-16T06:52:34.523-05:00Gorillas and humans diverged from one another earlier than thought<div class="separator" style="clear: both; text-align: center;">
</div>
Studying ancient humans and primates tells us more about our owns selves and what it means to be human, what it means to be of the species modern <i>Homo sapiens</i>. While we can look at our closest living relatives, apes and other primates, to theorize a great deal about how our ancestors acted 5 million years ago (mya), we also rely on fossil evidence and genetic studies. Studying human ancestors presents one very large problem: lack of fossil evidence. The <a href="http://www.oum.ox.ac.uk/thezone/fossils/intro/form.htm" target="_blank">fossilization process</a> requires just the right conditions at time of death and the right conditions afterwards. Thus, there are many gaps in our knowledge because the data simply isn't available. The fossils haven't been found.<br />
<br />
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: left; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh_Bx8lxtRXP_omXj-C_Iti9m9JcKtyzkMsHenFhVKiiOnAW7YNKoAli11KRib0p5p39OaW0yIV7ghWoW6pOB6hO2-X0NQmvMd2l1pw7WnS_g8OeXE1L9LfLP1JkSdD4jYOCg1gpqH1R34/s1600/Screen+Shot+2015-04-12+at+11.19.30+AM.png" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="186" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh_Bx8lxtRXP_omXj-C_Iti9m9JcKtyzkMsHenFhVKiiOnAW7YNKoAli11KRib0p5p39OaW0yIV7ghWoW6pOB6hO2-X0NQmvMd2l1pw7WnS_g8OeXE1L9LfLP1JkSdD4jYOCg1gpqH1R34/s320/Screen+Shot+2015-04-12+at+11.19.30+AM.png" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Juvenile mountain gorillas, Photo credit: <a href="https://www.flickr.com/photos/pamilne/8091262829/" target="_blank">Philip Milne</a></td></tr>
</tbody></table>
Scientists are particularly interested in fossils from 12-7 mya because this is around the time when African apes (gorillas, chimpanzees, and bonobos) and humans split. Yet, few fossils from this time have been discovered. <br />
<br />
Katoh and colleagues (2016) studied fossilized teeth found in Ethiopia's Afar Rift from an ancestral gorilla, called <i>Choroapithecus abyssinicus</i>, and the surrounding layers of earth these fossils were found in. Their results that suggest <i>C. abyssinicus </i>is older than previously believed. The teeth have been dated to 8 mya, which would mean that these ancestral gorillas and ancestral humans had to have diverged earlier in time than previously thought.<br />
<br />
Previous estimates of the split between African apes and humans suggested the two lines diverged more recently. Data from genetics suggests that humans and gorillas split somewhere between seven to eight million years ago. When <i>C. abyssinicus </i>was first discovered, it was found in deposits that are older than 8mya. The geology previously suggested that this species lived 10-10.5 mya (Suwa et al., 2007). Thus, this study provides some needed clarity on the age of these fossils.<br />
<br />
With these new results, we can place the age of these fossils at 8 mya, meaning this ancestral ape and humans likely split around 10 mya rather than 8 mya and suggesting the mutation rate between the two was slower than previously thought. We can also confirm that ancestral great apes evolved in Africa, as opposed to Europe or Asia.<br />
<br />
It's always impressive how a few extra teeth and a lot of hard work can transform what we know about our own origins.<br />
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;">Works cited:</span><br />
<br />
<span style="font-size: x-small;">Katoh, S., Beyene, Y., Itaya, T., Hyodo, H., Hyodo, M., Yagi, K., ... & Nakaya, H. (2016). New geological and palaeontological age constraint for the gorilla–human lineage split. Nature, 530(7589), 215-218. </span><br />
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;">Suwa, G., Kono, R. T., Katoh, S., Asfaw, B., & Beyene, Y. (2007). A new species of great ape from the late Miocene epoch in Ethiopia. Nature, 448(7156), 921-924.</span>Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.com0tag:blogger.com,1999:blog-7078978091325512838.post-36356813474321405572016-02-02T09:05:00.001-05:002016-02-02T09:05:23.194-05:00The spatial and temporal complexity of fruit species consumed by chimpsChimpanzees live in a variety of environments, thus the types of food they consume vary accordingly. We wouldn't expect a chimpanzee troop living in <a href="http://savannachimp.blogspot.com/" target="_blank">Fongoli </a>(a savanna) to consume the same foods as chimpanzees living in <a href="http://gombechimpanzees.org/" target="_blank">Gombe</a> (a tropical forest).<br />
<br />
That caveat aside, chimpanzees across habitats prefer fruits to other food types. <span class="current-selection">We know this because fruits
make up a greater proportion of their diet than would be expected given
fruit availability (Hladik, 1977; Tutin et al., 1997; Conklin-Brittain et al.,
1998; Wrangham et al., 1998; Doran-Sheehy et al., 2006). </span><span class="current-selection"><span class="current-selection">Fruits are high in energy and low in <b>secondary compounds</b>,
or digestive inhibitors or toxins, such as tannins or lignin. </span>(Remember that the fruits we see in a grocery store or at a food stand have been selectively bred to look and taste considerably different than most wild fruits). Interestingly, chimpanzees in </span>Guinea-Bissau consume mainly wild fruits and flowers even when they are in close proximity to agricultural areas <span class="current-selection">(Carvalho et al., 2015). Thus, it seems safe to conclude that fruits are high up on the desired menu.</span><br />
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<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; margin-left: 1em; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhkz3rRcaWXUtluidkRRd-MM0uzAcyQ_KNsQRsOr3Wpox4TKISgYjLH2YA0KwSAyedqPSlXm2Uu_XE7h4hQpb9fsqRJxXQruMXuxq3m9sFNk2sE0h6Hs4gPgO-4f5QiribpcFaBZ6m6VzM/s1600/Screen+Shot+2016-01-30+at+6.19.16+PM.png" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="222" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhkz3rRcaWXUtluidkRRd-MM0uzAcyQ_KNsQRsOr3Wpox4TKISgYjLH2YA0KwSAyedqPSlXm2Uu_XE7h4hQpb9fsqRJxXQruMXuxq3m9sFNk2sE0h6Hs4gPgO-4f5QiribpcFaBZ6m6VzM/s320/Screen+Shot+2016-01-30+at+6.19.16+PM.png" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Feeding on <i>Ficus sur</i> fruits, Photo credit: <a href="https://en.wikipedia.org/wiki/Ficus_sur#/media/File:Adult_female_and_infant_wild_chimpanzees_feeding_on_Ficus_sur.jpeg" target="_blank">Alain Houle</a></td></tr>
</tbody></table>
A recent study by Janmaat and colleagues (2016) looked at three populations of chimpanzees in tropical lowland rainforest, lowland tropical moist forest, and a moist evergreen tropical forest to better understand how chimpanzees access energy-rich foods. <span class="current-selection">They considered multiple food types that are high-energy: young leaves, unripe fruit, and ripe fruit. The authors also had a particular interest in large crops of ripe fruit. They described the probability of finding trees for each of the aforementioned, three food types and how predictable ripe fruit production is in each focal tree in regards to timing, frequency, and quantity of ripe fruit produced. </span><br />
<span class="current-selection"></span><br />
<span class="current-selection"><span class="current-selection"><span class="current-selection"><span class="current-selection"><span class="current-selection"> </span>The
authors found that individuals were more likely to encounter young
leaves or unripe fruit than ripe fruit, confirming that fruits present
more of a challenge than other food types. However, </span></span></span>over half of all of the trees chimpanzees encountered over the course of this study were species of fruiting trees consumed by chimps. Thus, finding a tree species known to produce an edible fruit isn't a monumental challenge for these populations. The challenge lies in timing. </span><span class="current-selection"><span class="current-selection"> </span></span><br />
<br />
<span class="current-selection"><span class="current-selection">There was considerable variation in the timing of fruit production within a population of a tree species. Within the same species, the length of fruit production varied: one individual may produce fruit for a few months over multiple years whereas another individual may fruit for many more months within the same period. There was also monthly variation in the size of fruit crops produced. Further variation within a species complicates matters for chimps even more, as they can't count on large crops of fruits in certain months, even within individual species.</span></span><br />
<span class="current-selection"><br /></span>
<span class="current-selection">Look for an upcoming post on the implications of finding ripe fruits in a complex environment. How might the ecology of chimpanzee habitat and their dietary choices affect their intelligence? </span><br />
<span class="current-selection"><br /></span>
<span style="font-size: x-small;"><span class="current-selection"><span style="font-size: small;">Links of potential interest:</span></span></span><br />
<a href="http://letstalkprimates.blogspot.com/2015/06/chimpanzees-understanding-cooking-and.html" target="_blank"><span style="font-size: x-small;"><span class="current-selection"><span style="font-size: small;">Chimps understand and choose to cook</span></span></span></a><br />
<span style="font-size: x-small;"><span class="current-selection"><span style="font-size: small;"><a href="http://letstalkprimates.blogspot.com/2015/04/female-chimps-are-more-likely-than.html" target="_blank">Female chimpanzees more likely to use tools when hunting than males</a> </span></span></span><br />
<span style="font-size: x-small;"><span class="current-selection"><span style="font-size: small;"> </span> </span></span><br />
<br />
<span style="font-size: x-small;"><span class="current-selection">Works cited:</span></span><br />
<br />
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;">Carvalho, J. S., Vicente,
L., & Marques, T. A. (2015). Chimpanzee (Pan troglodytes verus)
Diet Composition and Food Availability in a Human-Modified Landscape at
Lagoas de Cufada Natural Park, Guinea-Bissau. <i>International Journal of Primatology</i>, <i>36</i>(4), 802-822. </span></div>
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;">Conklin-Brittain, N. L.,
Wrangham, R. W., & Hunt, K. D. (1998). Dietary response of
chimpanzees and cercopithecines to seasonal variation in fruit
abundance. II. Macronutrients. <i>International Journal of Primatology</i>, <i>19</i>(6), 971-998.</span></div>
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;">Doran-Sheehy, D. M.,
Shah, N. F., & Heimbauer, L. A. (2006). Sympatric western gorilla
and mangabey diet: re-examination of ape and monkey foraging strategies.
<i>Cambridge Studies in Biological and Evolutionary Anthropology</i>, <i>48</i>, 49.</span></div>
<div class="gs_citr" id="gs_cit1" tabindex="0">
</div>
<div class="gs_citr" id="gs_cit1" tabindex="0">
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;">Hladik, C. M. (1977). Chimpanzees of Gabon and chimpanzees of Gombe: some comparative data on the diet. <i>Primate Ecology: Studies of Feeding and Ranging behaviour in Lemurs, Monkeys, and Apes</i>, 81-501.</span></div>
<div class="gs_citr" id="gs_cit1" tabindex="0">
</div>
<div class="gs_citr" id="gs_cit1" tabindex="0">
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;">Janmaat, K. R., Boesch,
C., Byrne, R., Chapman, C. A., Bi, G., Zoro, B., ... & Polansky, L.
(2016). Spatio‐temporal complexity of chimpanzee food: How cognitive
adaptations can counteract the ephemeral nature of ripe fruit. <i>American Journal of Primatology</i>.</span></div>
</div>
<span style="font-size: x-small;"></span></div>
<div class="gs_citr" id="gs_cit1" tabindex="0">
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;">Tutin, C. E., Ham, R. M.,
White, L. J., & Harrison, M. J. (1997). The primate community of
the Lopé Reserve, Gabon: diets, responses to fruit scarcity, and effects
on biomass. <i>American Journal of Primatology</i>, <i>42</i>(1), 1-24.</span></div>
</div>
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;">Wrangham, R. W.,
Conklin-Brittain, N. L., & Hunt, K. D. (1998). Dietary response of
chimpanzees and cercopithecines to seasonal variation in fruit
abundance. I. Antifeedants. <i>International Journal of Primatology</i>, <i>19</i>(6), 949-970.</span></div>
Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.com0tag:blogger.com,1999:blog-7078978091325512838.post-21242820361617952592016-01-11T11:37:00.001-05:002016-01-11T11:37:31.818-05:00Find yourself being spiteful? Blame these primate relatives.It looks like humans aren't the only ones who make an effort to punish or act negatively towards those we believe are undeserving. Leimgruber and colleagues (2015) recently published a new study on inequality and fairness in the journal <i>Evolution and Human Behavior.</i> They looked at whether capuchins (<i>Cebus apella</i>) would punish individuals who stole food or who benefited from an unequal distribution of food. The results and how they compare to other research might surprise you.<br />
<br />
Capuchins are a <b>New World Monkey</b> that are closely related to us. Humans and capuchins last shared a <b>common ancestor</b> roughly 30 million years ago (Fragaszy et al., 2004). These social primates live in large groups with dominance hierarchies. To learn more about this species, including their behavior, click <a href="http://pin.primate.wisc.edu/factsheets/entry/tufted_capuchin" target="_blank">here</a>.<br />
<br />
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: left; text-align: left;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgT6SqethOXQtatOiJxNdvYe0ASTAL2bHVwqguSQ9nqo5dVYDK6eD7SY3dB189YFgxGBgTYOcMYML1CjwVDO1iv6GfamKy6ixwRoDucfSphPUipWyh2EyrIWbklKemyicfqmSxJolEY0tU/s1600/Picture+1.png" imageanchor="1" style="clear: left; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="212" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgT6SqethOXQtatOiJxNdvYe0ASTAL2bHVwqguSQ9nqo5dVYDK6eD7SY3dB189YFgxGBgTYOcMYML1CjwVDO1iv6GfamKy6ixwRoDucfSphPUipWyh2EyrIWbklKemyicfqmSxJolEY0tU/s320/Picture+1.png" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><i>C. apella </i>Photo: <a href="https://www.flickr.com/photos/jmittermeier/3746966353" target="_blank">John Mittermeier</a></td></tr>
</tbody></table>
As you can probably guess, capuchins were tested in captivity to determine how they responded when a reward was not equally given and when a resource was stolen from them. Six individuals were tested. All individuals were tested against a low-ranking member of their social unit. Monkeys were tested in different enclosures but with a shared table that spanned both enclosures. Multiple conditions were tests: one where the test individual had access to the food, one where the test individual briefly had access to the food and then a researcher moved it to the low-ranking individual, and one where the low-ranking individual could steal the food outright. When the low-ranking individual gains control over a food source (due to the researcher moving the food source towards the individual), capuchins will pull on a rope that collapses the table holding the food. They will also do this when the low-ranking individual is given the ability to steal the food.<br />
<br />
Intentions don't seem to matter if you're a scorned capuchin. Capuchins punish the low-ranking individual even when that individual was not to blame for the unequal distribution of food. As Leimgruber stated when interviewed for Phys.org, capuchin monkeys appear to have a sort of "If I can't have it, no one can"attitude.<br />
<br />
Similar inequality studies have been conducted with chimpanzees, our closest living relatives. When we think of chimpanzees in comparison to capuchins, chimpanzees may seem more ruthless. They will <a href="http://news.sciencemag.org/plants-animals/2014/09/why-do-chimps-kill-each-other" target="_blank">kill one another</a> and they've been observed going to <a href="http://news.discovery.com/animals/zoo-animals/chimp-war-behavior.htm" target="_blank">"war" with other troops</a> of chimpanzees. Yet, chimpanzees will only make an effort to punish if the other individual is responsible for the inequality (<a href="http://www.pnas.org/content/109/37/14824.full" target="_blank">Riedl et al., 2012</a>). Perhaps capuchins are the anomaly or maybe this spiteful behavior does have its evolutionary origins 30 million years ago, making chimpanzees the anomaly. Similar studies will need to be done in other primate species to better understand the evolutionary history of this trait in primates.<br />
<br />
Of course, we can't actually blame capuchins for our spiteful actions (nor should we: let's not forget the power of human agency), but this study adds to our knowledge of human behavior while, perhaps, raising more questions.<br />
<br />
Links of potential interest:<br />
<br />
<a href="http://phys.org/news/2016-01-monkeys-spite.html" target="_blank">Phy.org article</a><br />
<a href="https://www.youtube.com/watch?v=-KSryJXDpZo" target="_blank">Video of capuchin fairness test</a><br />
<a href="https://www.ted.com/talks/frans_de_waal_do_animals_have_morals?language=en" target="_blank">Frans de Waal Ted Talk on Moral Behavior</a><br />
<br />
<span class="Apple-style-span" style="font-size: x-small;">Works cited:</span><br />
<span class="Apple-style-span" style="font-size: x-small;"><br /></span>
<span class="Apple-style-span" style="font-size: x-small;">Fragaszy, D. M., Visalberghi, E., & Fedigan, L. M. (2004). The complete capuchin: the biology of the genus Cebus. Cambridge University Press.</span><br />
<span class="Apple-style-span" style="font-size: x-small;"><br /></span>
<span class="Apple-style-span" style="font-size: x-small;">Leimgruber, K. L., Rosati, A. G., & Santos, L. R. (2015). Capuchin monkeys punish those who have more. Evolution and Human Behavior.</span><br />
<span class="Apple-style-span" style="font-size: x-small;"><br /></span>
<br />
<span class="Apple-style-span" style="font-size: x-small;">Riedl, K., Jensen, K., Call, J., & Tomasello, M. (2012). No third-party punishment in chimpanzees. Proceedings of the National Academy of Sciences, 109(37), 14824-14829.</span><br />
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<br />Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.com0tag:blogger.com,1999:blog-7078978091325512838.post-75507387843236047482015-12-26T12:34:00.001-05:002015-12-26T12:34:42.160-05:00New research on vocalizations, grooming, and social bonds <table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: left; margin-right: 1em; text-align: left;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhkulepCRYjba43c5mY8DbWXAOKYiq8NA4neU8sUjkzdItlgBCgck03DzG0YG8sAT_hBh-uc-5BdqSmXe-N4LRICAYM9rKf480Wu_etJWRHQMytUbeGyXyrz3U5RQIy7NTGk2xG53HO6II/s1600/DSC_0895.jpg" imageanchor="1" style="clear: left; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhkulepCRYjba43c5mY8DbWXAOKYiq8NA4neU8sUjkzdItlgBCgck03DzG0YG8sAT_hBh-uc-5BdqSmXe-N4LRICAYM9rKf480Wu_etJWRHQMytUbeGyXyrz3U5RQIy7NTGk2xG53HO6II/s320/DSC_0895.jpg" width="212" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><i>Lemur catta </i>Photo: author</td></tr>
</tbody></table>
Both grooming and vocalizing are linked to social bonds and relationships. Increases in the vocal repertoire of primates is correlated with group size and amount of time spent grooming (McComb and Semple, 2005). Previous research has shown that pairs of baboons (<i>Papio cynocephalus</i>) spend more time grooming one another (<b>allo-grooming</b>) and allo-groom more frequently if they are bonded socially (Silk et al., 2006). Dunbar first suggested that vocalizations may serve to act as a way of socially bonding when larger group sizes make grooming every member more difficult (1993; 2003; 2004). <br />
<br />
A study published this December provides further insight into the
reasons why small talk may have evolved and how it relates to social
relationships. Studying ring-tailed lemurs (<i>Lemur catta</i>), Kulahci and colleagues (2015) examined vocalizations and grooming. Four troops of free-ranging and semi-freeranging lemurs at the <a href="http://lemur.duke.edu/" target="_blank">Duke Lemur Center</a> and on <a href="http://www.stcatherinesisland.org/species/ringtailed-lemur/" target="_blank">St. Catherine's Island</a> were studied. Vocalization and grooming network outdegrees were calculated to determine who each individual initiated vocalizations and grooming towards. The grooming network outdegree was simply the number of individuals the individual in question groomed. The vocalization network outdegree was the number of individuals that the individual in question produced a vocal response towards upon hearing a call.<br />
<br />
Kulahci and colleagues (2015) found that ring-tailed lemurs were more selective in who they vocalized to than who they chose to groom: as troop size increased, lemurs groomed more individuals but they did not vocalize directly towards more individuals. Regardless of troop size, vocalization network outdegrees were lower than grooming network outdegrees, showing that lemur are picky about who they vocalize to but less so about who they groom. Individuals responded to the vocalizations of lemurs they groomed more frequently than they did lemurs they groomed less often.<br />
<br />
When audio playbacks were used, the same selectivity in vocalization responses was displayed. Thus, this selectivity in vocalizations is not due to olfactory or visual cues.<br />
<br />
While this study agrees with previous work highlighting the connection between grooming and vocalizations, it does not align with Dunbar's hypothesis (1993; 2003; 2004) that vocalizations allow an individual to maintain more social bonds than grooming would. Whereas we would have expected to see vocalizations increase with group size, the opposite was true for this study. Rather than vocalize with more troop members as group size increases, <i>L. catta </i>selectively vocalize and groom all members. Thus, vocalizations may be a better indicator of social bonds than grooming, at least in <i>L. catta</i>.<br />
<br />
Links of possible interest:<br />
<a href="http://www.reed.edu/biology/professors/srenn/pages/teaching/web_2008/dklj_site_final/home.html" target="_blank"> Social grooming in primates</a><br />
<a href="http://phys.org/news/2009-09-monkeys-grooming-habits-clues-socialise.html" target="_blank">How the size of the neocortex and the size of grooming clusters relate</a><br />
<a href="http://rstb.royalsocietypublishing.org/content/367/1597/1847" target="_blank">Derived vocal complexity of geladas</a><br />
<br />
<br />
<span style="font-size: x-small;">Sources:</span><br />
<br />
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;">Dunbar, R. I. (1993). Coevolution of neocortical size, group size and language in humans. <i>Behavioral and brain sciences</i>, <i>16</i>(04), 681-694.</span></div>
<span style="font-size: x-small;"><br /></span>
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;">Dunbar, R. I. (2003). The social brain: mind, language, and society in evolutionary perspective. <i>Annual Review of Anthropology</i>, 163-181.</span></div>
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;"> </span></div>
<div class="gs_citr" id="gs_cit1" tabindex="0">
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;">Dunbar, R. I. (2004). Gossip in evolutionary perspective. <i>Review of general psychology</i>, <i>8</i>(2), 100.</span></div>
<span style="font-size: x-small;"> </span></div>
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;">Kulahci, I. G., Rubenstein, D. I., & Ghazanfar, A. A. (2015). Lemurs groom-at-a-distance through vocal networks. <i>Animal Behaviour</i>, <i>110</i>, 179-186.</span></div>
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;"> </span></div>
<div class="gs_citr" id="gs_cit1" tabindex="0">
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;"><a href="http://rsbl.royalsocietypublishing.org/content/1/4/381" target="_blank">McComb, K., & Semple, S. (2005). Coevolution of vocal communication and sociality in primates. <i>Biology Letters</i>, <i>1</i>(4), 381-385.</a></span></div>
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;"> </span></div>
<div class="gs_citr" id="gs_cit1" tabindex="0">
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;">Silk, J. B., Altmann, J.,
& Alberts, S. C. (2006). Social relationships among adult female
baboons (Papio cynocephalus) I. Variation in the strength of social
bonds. <i>Behavioral Ecology and Sociobiology</i>, <i>61</i>(2), 183-195.</span></div>
</div>
</div>
Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.com0tag:blogger.com,1999:blog-7078978091325512838.post-52716674337095645892015-12-21T15:31:00.001-05:002015-12-21T15:31:38.803-05:00Another primate "sleeps" away hard times<b>Hibernation</b> allows an organism to lower its metabolism, heart rate, body temperature, and breathing in order to expend less energy during what may be a difficult time, such as a cold winter. Hibernation is a tactic commonly associated with rodents and polar bears but primates do it too. The fat-tailed dwarf lemur (<i>Cheirogaleus medius</i>) on the island of Madagascar hibernates during the dry season, using the fat in its tail to survive the winter. The Crossley's dwarf lemur (<i><span class="sciname">Cheirogaleus crossleyi</span></i>) and the Sibree's dwarf lemur (<i><span class="sciname">Cheirogaleus sibreei</span></i>) also hibernate. Some primates (<em>Microcebus murinus</em>, <i>Allocebus trichotis,</i> <em>G</em><em>alago moholi, </em>and others<em>) </em>will enter what is called <b>torpor</b>, during which body temperature and metabolism is lowered but for a period less than 24 hours. Lemurs were thought to be the only primate that hibernated, until a close cousin changed the game.<br />
<br />
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; margin-left: 1em; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjDQmvzTzZcAEnkPfCQ20ORi2bU3vb3DCO4coQsC8mQO0-QoLrN-g1APLGOL1ihnNWugyqqZ0D7qSli9bz-wgThMH4-JbPz_XX6iKdqfzPkiLz3LZMKMBxcAwmVQEVa4e9eX1Xzc0XtbwI/s1600/Screen+Shot+2015-12-21+at+2.54.07+PM.png" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="214" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjDQmvzTzZcAEnkPfCQ20ORi2bU3vb3DCO4coQsC8mQO0-QoLrN-g1APLGOL1ihnNWugyqqZ0D7qSli9bz-wgThMH4-JbPz_XX6iKdqfzPkiLz3LZMKMBxcAwmVQEVa4e9eX1Xzc0XtbwI/s320/Screen+Shot+2015-12-21+at+2.54.07+PM.png" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Pygmy slow loris. Photo: <span class="mw-mmv-source-author"><span class="mw-mmv-author">David Haring at Duke Lemur Center</span></span></td></tr>
</tbody></table>
It has recently been reported that the pygmy slow loris (<em>Nycticebus pygmaeus</em>), a nocturnal primate living in Cambodia, China, Laos, and Vietnam does in fact hibernate (Ruf et al., 2015). The authors behind this study set out to find a hibernating primate outside of Madagascar and they succeeded.<br />
<br />
Ruf and colleagues found it hard to believe that hibernation in primates would be restricted to only Madagascar, so they started thinking about what environmental conditions and physical characteristics would make an animal likely to hibernate. They hypothesized that a hibernating primate would be small, as most hibernating animals are (Ruf and Geiser, 2015), that the animal would live in an environment that is distinctly seasonal in temperatures and/or precipitation, and in an environment with seasonal changes in food availability. Given the primates known to use torpor, primates falling into the suborder <b>Strepsirrhines </b>seemed like their best bet.<br />
<br />
The pygmy slow loris fit their criteria. It was logical that a small primate facing cold temperatures in winter and low food availability would adapt using hibernation. Thus lowering energy requirements during a period of limited resources. While previous descriptions of the pygmy slow loris were in accord with hibernation (Ratajszczak, 1998; Streicher, 2005), no measurements had been taken. Thus, Ruf and colleagues decided to take some.<br />
<br />
After measuring temperature (but not metabolic rate) in five adults over 769 days total, animals hibernated for several days during midwinter interspersed with periods of activity and or torpor. On average, animals hibernated for 43 hours (± 3 hours with a range of 25.9-62.6 hours).<br />
<br />
Thus, evolutionary mechanisms have not limited hibernation in primates to Madagascar. As more research is done, it is possible that hibernation will be found in other primate species inhabiting seasonal environments.<br />
<br />
Links of possible interest:<br />
<a href="http://news.nationalgeographic.com/news/2004/06/0623_040623_lemurs.html" target="_blank">Discovery of hibernation in fat-tailed dwarf lemur</a><br />
<a href="http://phys.org/news/2013-05-primate-hibernation-common-previously-thought.html" target="_blank">Primate hibernation more common than previously thought</a><br />
<a href="http://evolutionbiology.com/definitions/the-costs-and-benefits-of-hibernation/" target="_blank">The costs and benefits of hibernation </a><br />
<br />
<span style="font-size: x-small;">Sources:</span><br />
<br />
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;">Ratajszczak, R. (1998).
Taxonomy, distribution and status of the lesser slow loris Nycticebus
pygmaeus and their implications for captive management. <i>Folia Primatologica</i>, <i>69</i>(Suppl. 1), 171-174.</span></div>
<br />
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;">Ruf, T., Streicher, U.,
Stalder, G. L., Nadler, T., & Walzer, C. (2015). Hibernation in the
pygmy slow loris (Nycticebus pygmaeus): multiday torpor in primates is
not restricted to Madagascar. <i>Scientific reports</i>, <i>5</i>.</span></div>
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;"><span itemprop="author" itemscope="" itemtype="http://schema.org/Person"><span itemprop="name">Ruf, T.</span></span> & <span itemprop="author" itemscope="" itemtype="http://schema.org/Person"><span itemprop="name">Geiser, F.</span></span> <cite itemprop="name headline">Daily torpor and hibernation in birds and mammals</cite>. <i>Biol. Rev.</i> <b>90</b>, 891–926, doi: 10.1111/brv.12137 (2015).</span><br />
<br />
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;">Streicher, U. (2005). Seasonal body weight changes in pygmy lorises Nycticebus pygmaeus. <i>Verhandlungsber. Zootierkrk</i>, <i>42</i>, 144-145.</span></div>
Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.com0tag:blogger.com,1999:blog-7078978091325512838.post-49056458395918323062015-10-14T10:27:00.002-04:002015-10-14T10:27:27.841-04:00Potential trouble for the endangered Udzungwa red colobus monkeyRecent genetic analysis of the Udzungwa red colobus monkey (<em>Procolobus gordonorum</em>) indicates the species might be in trouble in the future. This endangered monkey is <b>endemic</b> to the Udzungwa Mountains in Tanzania with population numbers currently in decline due to habitat loss and fragmentation (Struhsaker et al., 2008).<br />
<br />
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; margin-left: 1em; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhIKxbcmKetg2_V3pFLJOi_xEpLhgGChr7n5ewsbaL6R-1WKcsQijI3YtlKDOBpKKHeYngrfYrwBxyPA-0dAaMyXkOmAajC9-a_2MApMlgzKdYgYaI52I7uQpmYKqoD7infWegqGcfEsKo/s1600/Screen+Shot+2015-10-14+at+9.18.05+AM.png" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="232" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhIKxbcmKetg2_V3pFLJOi_xEpLhgGChr7n5ewsbaL6R-1WKcsQijI3YtlKDOBpKKHeYngrfYrwBxyPA-0dAaMyXkOmAajC9-a_2MApMlgzKdYgYaI52I7uQpmYKqoD7infWegqGcfEsKo/s320/Screen+Shot+2015-10-14+at+9.18.05+AM.png" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Udzungwa red colobus monkey, <a href="https://commons.wikimedia.org/wiki/File:Udzungwa_Red_Colobus_Stevage.JPG" target="_blank">credit:Stevage</a></td></tr>
</tbody></table>
Ruiz-Lopez and colleagues (2015) did genetic analyses on 121 individuals using DNA collected from fecal samples. Samples were collected from populations living in five forest fragments of varying size. Scientists then used what is termed, "landscape genetics," combining genetic analysis with <b>geographic-information-science</b> (GIS). Ruiz-Lopez and colleagues (2015) specifically looked at how fragmentation affects <i>P. gordonorum</i>'s genetic variation and what landscape features explained genetic differences. <br />
<br />
Results showed that the greatest genetic differences were found between monkeys that are separated by villages and/or by areas of land that experienced high densities of fires. Given that the red colobus monkey is <b>arboreal</b>, Ruiz-Lopez and colleagues were surprised forest coverage is not a significant factor contributing to genetic variation. Despite differences in forest fragment size and in population density of the monkeys themselves, genetic variation is not significantly affected by the forest fragment individuals inhabit. Forest fragmentation in this area is relatively new (Marshall, 2007), thus these populations have only recently been genetically isolated from each other. Perhaps not enough time has passed for differences to manifest.<br />
<br />
Ruiz-Lopez and colleagues (2015) are careful in their conclusions though and state that their findings do not necessarily prove that human activities are the main cause of this genetic variation. Human habitation and human-caused fires are likely contributing to the genetic differences, but these differences may be natural in origin, with humans simply reinforcing and maintaining genetic variation (Ruiz-Lopez et al., 2015).<br />
<br />
Although Ruiz-Lopez and colleagues are unable to show a direct cause-and-effect relationship, this work does highlight the importance of human activity on the landscape and its impact on genetic changes in primate populations. As of today, inbreeding is not a problem for the Udzungwa red colobus monkeys, but it could be in the future, given this new evidence suggests human impacts are contributing to genetic differentiation. This is one of the few studies to use landscape genetics in this region. <br />
<table id="detailsFooter"><tbody>
<tr><td><br /></td>
<td><br /></td></tr>
</tbody></table>
<br />
Links of interest:<br />
<a href="http://www.iucnredlist.org/details/40015/0" target="_blank">IUCN Redlist Page</a><br />
<a href="http://letstalkprimates.blogspot.com/2015/01/the-importance-of-wildlife-corridors-in.html" target="_blank">Why we need corridors</a><br />
<br />
<span style="font-size: x-small;">Works cited:</span><br />
<span style="font-size: x-small;">Marshall AR. (2007) <span class="journal">Disturbance in the Udzungwas: Responses of monkeys and trees to forest degradation</span>. PhD thesis University of York: UK.</span><br />
<span style="font-size: x-small;">Struhsaker, T, Butynski, T.M. & Ehardt, C. 2008. <i>Procolobus gordonorum</i>. The IUCN Red List of Threatened Species 2008: e.T40015A10302163. <a href="http://dx.doi.org/10.2305/IUCN.UK.2008.RLTS.T40015A10302163.en">http://dx.doi.org/10.2305/IUCN.UK.2008.RLTS.T40015A10302163.en</a> . </span><br />
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;">Ruiz-Lopez, M. J.,
Barelli, C., Rovero, F., Hodges, K., Roos, C., Peterman, W. E., &
Ting, N. (2015). A novel landscape genetic approach demonstrates the
effects of human disturbance on the Udzungwa red colobus monkey
(Procolobus gordonorum). <i>Heredity</i>.</span></div>
<br />
Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.com0tag:blogger.com,1999:blog-7078978091325512838.post-50408133060824424092015-10-05T08:54:00.000-04:002015-10-05T08:55:22.223-04:00Gregarious chimps have more grey matter in specific region of the brain<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: left; text-align: left;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhST6aeQ_iUdMPryEJ3M3w7cGlZbvSy91e14ZbFqWModbBTuvgSJJPhZKkmYzf7H8fuexD9B_hRCG67ED3I27-seCKoyGRGw-vOQzerqFyzhaufRpcOsWmoyxtXeearuQBzk0KFlb03oSs/s1600/Screen+Shot+2014-10-18+at+9.00.08+PM.png" imageanchor="1" style="clear: left; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="269" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhST6aeQ_iUdMPryEJ3M3w7cGlZbvSy91e14ZbFqWModbBTuvgSJJPhZKkmYzf7H8fuexD9B_hRCG67ED3I27-seCKoyGRGw-vOQzerqFyzhaufRpcOsWmoyxtXeearuQBzk0KFlb03oSs/s320/Screen+Shot+2014-10-18+at+9.00.08+PM.png" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><a href="https://www.flickr.com/photos/ucumari/4669393822/in/photolist-avbFK8-94yvCD-7UHYD4-oWJxMx-ehnmhe-arpnwP-6mSSp3-29zXHS-kFBqi6-3akF4o-87BS73-bBR2cs-nQFwSQ-eh2z87-5YzifQ-6tyzJw-bCBPgJ-787Ty-oNV1W3-kAPVdg-6Dzh2H-4VeYw9-fmzNqo-bNatp-breara-jninqr-g9Fokm-ay1Cam-5nPL6-g6Eimo-nmDhUW-7dhFR4-9jNQFG-8zMmft-5DiXck-6vD1wG-59U26Y-4AetBE-adxHvw-eiu8VH-4QnzEt-6HyNwb-7iPDu4-oJfoy2-aEsaCb-8oWuSc-F6XDW-3bm8iT-izL1zF-os2GPu" target="_blank">Chimpanzees with offspring, Photo credit: flickr user Valerie</a></td></tr>
</tbody></table>
As one of our closest living relatives, studying the behavior,
ecology, and anatomy of chimps provides a look back in time as to what
the <b>last common ancestor</b> of chimpanzees and humans may have been
like. A recent study examined the brain structure of over one hundred
chimpanzees to understand how personality and the brain are connected.<br />
<br />
Latzman
and colleagues (2015) studied 107 captive chimpanzees by using MRIs and
an assessment composed of 41 questions about each individual chimp's
personality that was conducted by staff members who care for the
animals. The article did not state how long these staff members worked
with the chimpanzees, only that they felt they could assess their
personalities.<br />
<br />
Latzman and colleagues (2015) showed
that the volume of gray matter and asymmetry of various regions of the
frontal cortex are correlated. Grey matter, found mainly on the outside
of the brain, is composed on neuronal cells and unmyelinated axons. (To
learn more about grey matter, click <a href="http://www.differencebetween.net/science/health/difference-between-grey-and-white-matter/" target="_blank">here</a>.)
Chimpanzees ranked as more dominant, open, and extraverted have greater
average grey matter in the frontal cortex of their brains. Extraversion
in this article is defined as "energetic approach orientated." Their
research also shows that frontal cortex asymmetry, or lack of
equality/symmetry, is associated (but not correlated) with dominance,
extraversion, and unpredictability. <table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg_hRlvGKimfks5SqRPpi4cf2MQg6KYEA1NG06FUzhkqYgLTydLEnk6vjhtG2os74GhY4S0_4Nm_ZsjEq6YxCys_a_R__V2iIt5Ku8-Fv_Mv4z8VwkZolVV6HVFqa9LDnNj7jt_po4Yoo0/s1600/Screen+Shot+2015-09-30+at+12.14.29+PM.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="298" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg_hRlvGKimfks5SqRPpi4cf2MQg6KYEA1NG06FUzhkqYgLTydLEnk6vjhtG2os74GhY4S0_4Nm_ZsjEq6YxCys_a_R__V2iIt5Ku8-Fv_Mv4z8VwkZolVV6HVFqa9LDnNj7jt_po4Yoo0/s400/Screen+Shot+2015-09-30+at+12.14.29+PM.png" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Source: <a href="https://commons.wikimedia.org/wiki/File:Brain_areas.jpg" target="_blank"><i>Biological Psychology </i>6e via Wikipedia</a></td></tr>
</tbody></table>
<br />
There are limitations to this study, as Latzman and colleagues (2015)
mention. It is impossible to determine the causal relationship. Do
personality differences create these structural differences in the
brain? Or do structural differences in the brain create these
personalities differences? As of right now, we can't answer this
question. Interpretations of these findings are also limited by our own
understanding of the brain, and we have much to still learn about the
structure and function of this complex organ.<br />
<br />
Yet,
because of this study we have a greater understanding of the biological
bases of behavior and personality. Latzman and colleagues (2015) are
the first to study the frontal cortex of the brain and personality in
chimpanzees. As we know, chimpanzees are an excellent model for human
behavior and personality because they are so closely related to humans.
Studies such as this one allow us to refine our understanding of the
evolution of our own species. <br />
<br />
Food for thought: Would we expect to see the same results in bonobos? Orangutans? Lemurs?<br />
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;"><span style="font-size: small;">Links of interest:</span></span><br />
<a href="http://letstalkprimates.blogspot.com/2015/06/chimpanzees-understanding-cooking-and.html" target="_blank"><span style="font-size: x-small;"><span style="font-size: small;">Cooking chimpanzees</span></span></a><br />
<a href="http://letstalkprimates.blogspot.com/2015/06/rank-affects-females-likelihood-to-seek.html" target="_blank"><span style="font-size: x-small;"><span style="font-size: small;">Female friendship in chimpanzees</span></span></a><br />
<span style="font-size: x-small;"><span style="font-size: small;"><a href="http://letstalkprimates.blogspot.com/2015/04/female-chimps-are-more-likely-than.html" target="_blank">Differences in tool use between males and females</a> </span></span><br />
<br />
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;">Works cited:</span><br />
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;">Robert D. Latzman, Lisa K. Hecht, Hani D. Freeman, Steven J. Schapiro, William D. Hopkins. <b>Neuroanatomical correlates of personality in chimpanzees (Pan troglodytes): Associations between personality and frontal cortex</b>. <i>NeuroImage</i>, 2015; 123: 63 DOI: <a href="http://dx.doi.org/10.1016/j.neuroimage.2015.08.041" rel="nofollow" target="_blank">10.1016/j.neuroimage.2015.08.041</a></span><br />
<br />
<br />
Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.com0tag:blogger.com,1999:blog-7078978091325512838.post-17135621285654194462015-09-21T21:24:00.002-04:002015-09-28T13:20:46.366-04:00Male squirrel monkeys made to see in living color<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: left; margin-right: 1em; text-align: left;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi2QRm3rzwpND4A5yg531Isj3iIbjSn4QEetrNYgV4S_G3ReWCv3UI2r_hKyEEwVMSyskLbzGXl0orAkZPrqxw6xZrs_OMCleqva-Gjo8yyocdHMlKvnLiE4E1gJVnRQ5ENcesYvLBO8gg/s1600/Screen+Shot+2015-09-27+at+11.11.25+AM.png" imageanchor="1" style="clear: left; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="211" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi2QRm3rzwpND4A5yg531Isj3iIbjSn4QEetrNYgV4S_G3ReWCv3UI2r_hKyEEwVMSyskLbzGXl0orAkZPrqxw6xZrs_OMCleqva-Gjo8yyocdHMlKvnLiE4E1gJVnRQ5ENcesYvLBO8gg/s320/Screen+Shot+2015-09-27+at+11.11.25+AM.png" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Squirrel monkey in Bolivia. Photo: author</td></tr>
</tbody></table>
Squirrel monkeys, like many <b>New World Monkeys</b>, are a bit unusual when it comes to their vision. Males are <b>dichromatic</b>, meaning that they do not have the ability to see red wavelengths but can see blue and green wavelengths. Females on the other hand, may be dichromatic or they may be <b>trichromatic</b> like us, able to see blues, greens, and reds. Males are dichromatic because trichromatic vision requires two copies of a certain opsin gene, a gene that is found on the X chromosome. Thus, females, who have two Xs, likely (but not always) carry two copies of the gene. The majority of female squirrel monkey can see shades of green and shades of red. Male monkeys have the gene that codes for seeing green colors but not the gene that allows them to see red.<br />
<br />
When we refer to color blindness in humans, often what we really mean is that the person has dichromatic color vision. True color blindness in humans, where the person can only see in black and white, is very rare, although something similar does occur in another New World Monkey. Night monkeys have very poor color vision. As their name suggests, these monkeys are active only at night. Thus, seeing reds, greens, and blues isn't very advantageous given their environment. Over time, owl monkeys have evolved so that they have fewer cones, which allow the eye to see colors, and more rods, which allow the eye to distinguish blacks and whites. To further adapt for their mainly nocturnal lifestyle, the size of their eyes has also expanded. Again, being <b>monochromatic</b> is rare in humans, yet dichromatic color vision does occur in one out of twelve men. <br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhHYFuvMs3YtnuNm709DmwFt9w7a0Y8ATJDEMCFrpFt7Z2MgpZbUW8d93pmpLztR1UTGYU8qvv98kBNy52n98MDF3Uz6eOk2J1B3OvKCL7Lxmq2L2GFlpFti4vzCfP_drjO5dJojZ5B5Yc/s1600/Screen+Shot+2015-09-27+at+11.34.40+AM.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="207" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhHYFuvMs3YtnuNm709DmwFt9w7a0Y8ATJDEMCFrpFt7Z2MgpZbUW8d93pmpLztR1UTGYU8qvv98kBNy52n98MDF3Uz6eOk2J1B3OvKCL7Lxmq2L2GFlpFti4vzCfP_drjO5dJojZ5B5Yc/s320/Screen+Shot+2015-09-27+at+11.34.40+AM.png" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><a href="https://en.wikipedia.org/wiki/Photoreceptor_cell" target="_blank">Visible Wavelengths</a> Dichromats lack red cones</td></tr>
</tbody></table>
Now, there may be hope for those who have dichromatic color vision and it's thanks to research done in squirrel monkeys. Two male squirrel monkeys have been made to see all three wavelengths.<br />
<br />
Mancuso and colleagues injected the gene that would allow two male squirrel monkeys to see red into a virus, and then they injected that virus behind the retina. (Review your eye anatomy <a href="http://www.allaboutvision.com/resources/anatomy.htm" target="_blank">here</a>.) Two years later, the monkeys have had no side effects and are able to see all three wavelengths. Squirrel monkey brains, like our own, are quite plastic, meaning they can change. These two animals can now distinguish reds from greens and their brains have apparently rewired themselves so that seeing and processing information about the red wavelength can be done.<br />
<br />
Why do humans see in all three colors? There isn't a certain answer. Multiple hypotheses have been proposed. Peter Lucas, my former professor, believes our ability to see reds was advantageous in helping our ancestors see young red leaves, which are especially nutritious, against a background that is mostly made up of shades of green (Lucas et al., 1998). Our closest living relatives, chimpanzees and gorillas, consume a diet mainly composed of leaves. Or perhaps we see reds because red fruit is often ripe and therefore we can distinguish ripe fruit against a green background (Allen, 1879; Mollon, 1989; Fleagle, 1999). Yet, if this were the complete answer, wouldn't we expect New World Monkeys, who consume fruit, to see red wavelengths? Another hypothesis suggests that our ability to see shades of red occurred so that male Old World Monkeys could more easily discern the sexual swellings of females that were in estrous (Liman and Innan, 2003).<br />
<br />
Regardless of why trichromatic vision evolved in our ancestors, it seems that those humans unable to see all three wavelengths may one day be able to enjoy the Christmas colors following <b>gene therapy</b>. Trials in humans are underway and we have two male squirrel monkeys to thank for that.<br />
<br />
<br />
Links of interest:<br />
<a href="http://anthro.palomar.edu/primate/color.htm" target="_blank">Color vision in primates</a><br />
<a href="http://micro.magnet.fsu.edu/primer/lightandcolor/humanvisionintro.html" target="_blank">Color vision in humans </a><br />
<a href="http://pin.primate.wisc.edu/factsheets/entry/owl_monkey" target="_blank">Night monkeys and their morphology </a><br />
<a href="http://www.sciencedaily.com/releases/2014/12/141218210100.htm" target="_blank">A molecular view of how human color vision evolved</a><br />
<br />
<br />
<span style="font-size: x-small;">Works cited:</span><br />
<span style="font-size: x-small;"> Allen, G. 1879. The colour-sense: its origins and development. Trubner, London.</span><br />
<span style="font-size: x-small;">Fleagle, J. G. 1999. <i>Primate adaptation and evolution</i>. 2nd ed. Academic Press, San Diego, CA. </span><br />
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;">Liman, E. R., &
Innan, H. (2003). Relaxed selective pressure on an essential component
of pheromone transduction in primate evolution. <i>Proceedings of the National Academy of Sciences</i>, <i>100</i>(6), 3328-3332</span></div>
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;">Lucas, P. W., Darvell, B.
W., Lee, P. K. D., Yuen, T. D. B., & Choong, M. F. 1998. Colour
cues for leaf food selection by long-tailed macaques (Macaca
fascicularis) with a new suggestion for the evolution of trichromatic
colour vision. <i>Folia Primatologica</i>, <i>69</i>(3), 139-154. </span></div>
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;">Mancuso, K. <i>et al. </i> <span class="journalname">Nature</span> advanced online publication, doi:10.1038/nature08401 (2009). </span></div>
<div class="gs_citr" id="gs_cit1" tabindex="0">
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;">Mollon, J. D. 1989. “Tho'she kneel'd in that place where they grew…” The uses and origins of primate colour vision. <i>Journal of Experimental Biology</i>, <i>146</i>(1), 21-38.</span></div>
</div>
Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.com0tag:blogger.com,1999:blog-7078978091325512838.post-23115579165989165692015-09-03T15:14:00.001-04:002015-09-03T15:15:49.042-04:00Female orangutans may prefer males with large cheekpads<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: left; text-align: left;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiy1xsyigrk3aytVHC5wZDlq_oyWup_e_CPFn5oq88xqJymdjIGw-kdqNjAK5zrwORKbt2u4n4yDL5YTXIILod_onBMOM20Wbuk1eX-V1EUIv8TaLGw0eudLMSD7zLjakSF1jX1yU92o8Y/s1600/Screen+Shot+2015-09-02+at+12.37.17+PM.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="238" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiy1xsyigrk3aytVHC5wZDlq_oyWup_e_CPFn5oq88xqJymdjIGw-kdqNjAK5zrwORKbt2u4n4yDL5YTXIILod_onBMOM20Wbuk1eX-V1EUIv8TaLGw0eudLMSD7zLjakSF1jX1yU92o8Y/s320/Screen+Shot+2015-09-02+at+12.37.17+PM.png" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Dominant male named Kiko at NZP. Photo: author</td></tr>
</tbody></table>
Orangutans display an interesting form of <b>sexual dimorphism</b> in that males have large cheek pads but females do not. Males are also larger and have large throat sacs that aid them when they make long calls, which advertise to females and tell other orangutans, "I am here!" However, not all males develop this large size, cheek pads, and throat sac. The cheek pads, large size and throat sacs are characteristic of dominant males. Thus, orangutan males display <b>bimaturism</b>, meaning the timing of development differs. Some males develop these dominant characteristics much sooner than others. Because adult males aren't always large and with the distinguishing cheek pads and throat sacs, it can be quite difficult to tell non-dominant males and females apart.<br />
<br />
<br />
These non-dominant males aren't juvenile or infertile. They are perfectly capable of reproducing and previously have been shown to produce about half of all wild orangutan offspring (Utami et al., 2002). These two forms of adult males have different strategies when it comes to mating. The dominant males defend their territory. Their homerange is very large and includes multiple females. Non-dominant males are able to gain access to females when the dominant male isn't around.<br />
<br />
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; text-align: left;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhk3Nr5-eIjGGKGfW9d4AJy4J2-QopczDAEugZ_NV1fb_mJT0knEvLocn86kPw6uZbna2BIzmGeFh64uuIq5waws4pZ8ToMJUdUFLRv_vjtIc6LK6F1Ci77QRGwVgO6R3im0VWEyd5aDug/s1600/Screen+Shot+2015-09-02+at+12.38.49+PM.png" imageanchor="1" style="clear: left; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="140" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhk3Nr5-eIjGGKGfW9d4AJy4J2-QopczDAEugZ_NV1fb_mJT0knEvLocn86kPw6uZbna2BIzmGeFh64uuIq5waws4pZ8ToMJUdUFLRv_vjtIc6LK6F1Ci77QRGwVgO6R3im0VWEyd5aDug/s200/Screen+Shot+2015-09-02+at+12.38.49+PM.png" width="200" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Bonnie(female) at NZP. Photo: author</td></tr>
</tbody></table>
A new study resulting from eight years of field research at Tanjung Puting National Park on the island of Borneo found that females prefer dominant males with cheek pads. This is the longest study to have been done at one site in a single population of individual orangutans in terms of orangutan paternity. Banes and colleagues (2015) determined parentage for orangutans inhabiting the homerange used by Kuasasi, a dominant male. They determined he produced far more offspring once he achieved dominance and that he fathered the majority of offspring in the area. This is in contrast to what Utami and colleagues found in 2002 in Sumatra in which unflanged males produced half of the offspring. <br />
<br />
This more recent study is arguably limited by the fact that researchers determined the parentage of orangutans in one dominant male's range (Kuasasi). It is possible this is just one very successful male. Or, females are in fact choosing dominant, flanged males over unflanged males. The authors also point out that their study site may affect their results. Camp Leakey is characterized by both wild orangutans and individuals that were once captive but released to the area in the 70s. Orangutans at this site also receive medical treatment, which may mean that dominant males are surviving attacks that they otherwise would not, affecting the population.<br />
<br />
Conducting studies on paternity and life history variables on orangutans is very difficult given that, other than humans, orangutan offspring take the longest to reach adulthood of any primate. Females will reproduce every eight years (Gladikas and Wood, 1990), thus answering these types of questions remains difficult. <br />
<br />
Links of interest:<br />
<a href="http://eol.org/pages/326450/overview" target="_blank">Encyclopedia of Life Page on Bornean Orangutans</a><br />
<a href="http://www.iucnredlist.org/details/17975/0" target="_blank"> IUCN Redlist Page on Bornean Orangutan</a><br />
<a href="http://www.sciencedaily.com/releases/2013/03/130305080648.htm" target="_blank">Monopoly of the male orangutan </a><br />
<a href="http://www.soundboard.com/sb/Orangutan_Sounds" target="_blank">Orangutan long call</a><br />
<br />
<br />
<span style="font-size: x-small;">Sources:</span><br />
<br />
<span style="font-size: x-small;">Galdikas BMF, Wood JW (1990) Birth spacing patterns in humans and apes. Am J Phys Anthropol 83:185–191 </span><br />
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;">Graham L. Banes, Biruté M. F. Galdikas, Linda Vigilant. Male orang-utan bimaturism and reproductive success at Camp Leakey in Tanjung Puting National Park, Indonesia. <i>Behavioral Ecology and Sociobiology</i>, 2015; DOI: <a href="http://dx.doi.org/10.1007/s00265-015-1991-0" rel="nofollow" target="_blank">10.1007/s00265-015-1991-0</a></span><br />
<br />
<div class="gs_citr" id="gs_cit1" tabindex="0">
<span style="font-size: x-small;">Utami, S. S., Goossens,
B., Bruford, M. W., de Ruiter, J. R., & van Hooff, J. A. (2002).
Male bimaturism and reproductive success in Sumatran orang-utans. <i>Behavioral Ecology</i>, <i>13</i>(5), 643-652.</span></div>
<br />
<br />
<br />
<br />Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.com0tag:blogger.com,1999:blog-7078978091325512838.post-21405534497963203302015-08-26T11:44:00.001-04:002015-08-26T11:44:07.172-04:00Chimpanzee populations in Uganada greater than previously thought Chimpanzees (<i>Pan troglodytes</i>) are currently listed as endangered by the International Union for the <span id="goog_148232727"></span><span id="goog_148232728"></span>Conservation of Nature (IUCN) due to threats from habitat loss and degradation causing a decrease in population numbers that will likely continue (Oates et al., 2008). However, a recent study examining chimpanzee numbers in Uganda gives us reason to hope for our close primate relatives. In the open access journal BMC Ecology, McCarthy and colleagues report that 15 months of data collection has lead them to determine that over two hundred and fifty chimpanzees live in a <b>corridor</b> that was previously assumed to hold ~seventy individuals.<br />
<br />
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: left; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhST6aeQ_iUdMPryEJ3M3w7cGlZbvSy91e14ZbFqWModbBTuvgSJJPhZKkmYzf7H8fuexD9B_hRCG67ED3I27-seCKoyGRGw-vOQzerqFyzhaufRpcOsWmoyxtXeearuQBzk0KFlb03oSs/s1600/Screen+Shot+2014-10-18+at+9.00.08+PM.png" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="269" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhST6aeQ_iUdMPryEJ3M3w7cGlZbvSy91e14ZbFqWModbBTuvgSJJPhZKkmYzf7H8fuexD9B_hRCG67ED3I27-seCKoyGRGw-vOQzerqFyzhaufRpcOsWmoyxtXeearuQBzk0KFlb03oSs/s320/Screen+Shot+2014-10-18+at+9.00.08+PM.png" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><a href="https://www.flickr.com/photos/ucumari/4669393822/in/photolist-avbFK8-94yvCD-7UHYD4-oWJxMx-ehnmhe-arpnwP-6mSSp3-29zXHS-kFBqi6-3akF4o-87BS73-bBR2cs-nQFwSQ-eh2z87-5YzifQ-6tyzJw-bCBPgJ-787Ty-oNV1W3-kAPVdg-6Dzh2H-4VeYw9-fmzNqo-bNatp-breara-jninqr-g9Fokm-ay1Cam-5nPL6-g6Eimo-nmDhUW-7dhFR4-9jNQFG-8zMmft-5DiXck-6vD1wG-59U26Y-4AetBE-adxHvw-eiu8VH-4QnzEt-6HyNwb-7iPDu4-oJfoy2-aEsaCb-8oWuSc-F6XDW-3bm8iT-izL1zF-os2GPu" target="_blank">Chimpanzees with offspring, Photo credit: flickr user Valerie</a></td></tr>
</tbody></table>
The Budongo and Bugoma Forest Reserves in Uganda are two large areas of protected land separated by an unprotected area that contains villages, agricultural fields, along with grasslands and forest. It's not your typical, ideal chimpanzee habitat. This corridor is dominated by humans, with 107 humans per square km (NPHC, 2014). Yet, studies like this one have obvious merit as we lose more and more pristine habitat.<br />
<br />
Researchers collected fecal samples and genotyped those samples from 2011-2013. They then used models to determine the number of individuals. This noninvasive method is more accurate than counting the number of nests chimpanzees make at night in order to determine the number of individuals. (Chimpanzees make nests out of branches and forest materials every night that they sleep in. See a video <a href="https://www.youtube.com/watch?v=GW4UcdwroBU" target="_blank">here</a>.) Using this method, they were able to determine that there are at least nine communities, each with anywhere between eight to thirty-three individuals. Because not all areas of the unprotected corridor were not sufficiently sampled in this study, it is possible this is a conservative estimate, and numbers may be even higher.<br />
<br />
McCarthy and colleagues point out that chimpanzees exhibit a great deal of behavioral flexibility, which likely accounts for how they've coped with a less-than-ideal environment. Chimps are <b>omnivores</b> and can adapt their diet if they need to, including human-cultivated foods. Provided a lack of pressure from hunting, it is worth considering these stretches of land that previously may have been overlooked as viable areas worthy of conserving. The next steps will be understanding just how the chimps are doing so well in this habitat. What behavioral changes are they making? <br />
<br />
Links of interest:<br />
<a href="http://www.iucnredlist.org/details/15933/0" target="_blank">IUCN Redlist page on chimpanzees </a><br />
<a href="http://maps.iucnredlist.org/map.html?id=15933" target="_blank">Map showing current range of chimpanzees </a><br />
<a href="http://letstalkprimates.blogspot.com/2015/04/the-fate-of-western-lowland-gorillas.html" target="_blank">The fate of western lowland gorillas and chimpanzees over the next decade </a><br />
<a href="http://letstalkprimates.blogspot.com/2014/12/how-human-are-chimps-differences-and.html" target="_blank">How human are chimps?</a><br />
<span style="font-family: inherit;"><span style="font-size: x-small;"><br /></span></span>
<span style="font-family: inherit;"><span style="font-size: x-small;">Works cited:</span></span><br />
<table id="detailsFooter"><tbody>
<tr><td><span style="font-family: inherit;"><span style="font-size: x-small;"><b></b><br /></span></span></td>
<td><br /></td></tr>
</tbody></table>
<span style="font-size: x-small;"><span style="font-family: inherit;">Maureen S McCarthy, Jack D Lester, Eric J Howe, Mimi Arandjelovic, Craig B Stanford, Linda Vigilant. Genetic censusing identifies an unexpectedly sizeable population of an endangered large mammal in a fragmented forest landscape. <i>BMC Ecology</i>, 2015; 15 (1) DOI: <a href="http://dx.doi.org/10.1186/s12898-015-0052-x" rel="nofollow" target="_blank">10.1186/s12898-015-0052-x</a></span></span><br />
<span style="font-size: x-small;"><span style="font-family: inherit;"><em>NPHC 2014 provisional results report</em>. Uganda Bureau of Statistics, Kampala; 2014.</span></span><span style="font-family: inherit;"><span style="font-size: x-small;"> </span></span><br />
<span style="font-family: inherit;"><span style="font-size: x-small;"><span style="font-family: inherit;">Oates, J.F., Tutin, C.E.G., Humle, T., Wilson, M.L., Baillie, J.E.M., Balmforth, Z., Blom, A., Boesch, C., Cox, D., Davenport, T., Dunn, A., Dupain, J., Duvall, C., Ellis, C.M., Farmer, K.H., Gatti, S., Greengrass, E., Hart, J., Herbinger, I., Hicks, C., Hunt, K.D., Kamenya, S., Maisels, F., Mitani, J.C., Moore, J., Morgan, B.J., Morgan, D.B., Nakamura, M., Nixon, S., Plumptre, A.J., Reynolds, V., Stokes, E.J. & Walsh, P.D. 2008. Pan troglodytes. The IUCN Red List of Threatened Species. Version 2015.2. <www.iucnredlist.org>. <a href="http://www.biomedcentral.com/sfx_links?ui=s12898-015-0052-x&bibl=B103"><img align="absmiddle" alt="OpenURL" src="http://www.biomedcentral.com/sfx_links?getImage" /></a></span> </span></span>Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.com0tag:blogger.com,1999:blog-7078978091325512838.post-15755427186440832332015-07-15T14:27:00.001-04:002015-07-15T14:27:41.860-04:00How hurricane severity affects extinction probabilities for howler monkeys<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; margin-left: 1em; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiDifWA3g1uk3qF6zwR1aTxEdGp0x-vGIS4HXO_br8xv2SOwhd6rTAvewHmBuxwobZ5uaS6SnlUCfuQ_OQxM7lQBQi2t3XkR87jA_pzih8k89Y01A59JXs0Fz87n1GQtWleIKCkIlJgDT4/s1600/Screen+Shot+2015-07-15+at+1.13.19+PM.png" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiDifWA3g1uk3qF6zwR1aTxEdGp0x-vGIS4HXO_br8xv2SOwhd6rTAvewHmBuxwobZ5uaS6SnlUCfuQ_OQxM7lQBQi2t3XkR87jA_pzih8k89Y01A59JXs0Fz87n1GQtWleIKCkIlJgDT4/s320/Screen+Shot+2015-07-15+at+1.13.19+PM.png" width="254" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Howler on Barro Colorado Is. Photo: <a href="https://www.flickr.com/photos/vsmithuk/6784458279/" target="_blank">Vince Smith</a></td></tr>
</tbody></table>
Howler monkeys are known for their long, bellowing calls that can be heard in the forests of Central and South America. There are five <b>subspecies</b>, the taxonomic rank below species, of howler monkeys. <i>Alouatta palliata mexicana</i> is a critically endangered subspecies found in parts of Mexico and Guatemala. Ameca y Juárez and colleagues had the idea to examine how hurricanes affect population numbers of this <b>arboreal</b>, New World primate. Using data from 1988 to 2002, the authors modeled how hurricane intensity affects extinction likelihood of local populations of this New World primate. They also wanted to know which human disturbance, hunting or habitat loss, had a greater impact when combined with different intensities of hurricanes. <br />
<br />
Previous studies have examined how other species of howler monkeys have been impacted by hurricanes on a short-term basis, but this study is the first to look at the effects over a long period of time. The area in which <i>A. p. mexicana </i>inhabits is experiencing more hurricanes lately (Manson et al., 2009; Portilla-Ochoa et al., 2006), thus this study is of increasing relevance. <br />
<br />
Studying <i>A. p. mexicana </i>living on Agaltepec Island in Mexico, which is isolated and predator-free (including human predators), Ameca y Juárez and colleagues estimated predator, hunting, and habitat loss pressures from other <i>A. p. mexicana</i> populations in the area. They used population viability analysis (PVA) to determine the impact of different hurricane intensities on howler monkeys' quasi-extinction risk, or the probability of reaching a population size in which additional threats could cause the loss of the entire population.<br />
<br />
The lowest degree hurricane disturbance result in a 28% quasi-extinction risk forty years later. Baseline estimates of hurricane intensity result in a 74% risk. Overall, the authors found that hurricanes have the ability to exceed the risk of human impacts. The combination of hurricanes and habitat loss have a substantially faster effect than when hurricanes and hunting are paired together. It is the decrease in survival of adults that most affects the quasi-extinction rates, with adult males having an especially significant effect on the population. <br />
<br />
The authors do point out that recurrent exposure to disturbances, including hurricanes, can be expected to affect the adaptability over time, thus reducing the likelihood the species will go extinct from the disturbance. Thus, the relationship between quasi-extinction risk and hurricane intensity won't be lineal in reality, as populations frequently exposed to hurricanes over time will adapt to lessen or moderate the negative effects.<br />
<br />
As more frequent and intense hurricanes are expected in the future, studies such as this one allow us to determine how primate populations might be affected. Future modelling of hurricane intensity and frequency may incorporate other factors likely to affect population numbers, such as <b>inbreeding</b>. <br />
<br />
Food for thought:<br />
How might conservation biologists use information from this study to protect <i>A. p. mexicana</i>?<br />
How might this study apply to other species of primates and other animal species in general?<br />
<br />
Links of interest:<br />
<a href="http://www.iucnredlist.org/details/925/0" target="_blank">IUCN's page on <i>A. palliata</i></a><br />
<a href="http://www.care2.com/causes/how-do-wild-animals-survive-hurricanes.html" target="_blank">How animals survive hurricanes</a><i> </i><br />
<a href="http://www.salon.com/2015/07/13/deadly_floods_and_record_heat_scientists_say_climate_change_made_these_recent_extreme_weather_events_worse/" target="_blank">Why we should expect more extreme weather </a><br />
<a href="https://www.youtube.com/watch?v=-vxlnZ8BihI" target="_blank">Howler monkeys' call</a><br />
<br />
<br />
<span style="font-size: x-small;">Works cited:</span><br />
<span style="font-size: x-small;">Ameca y Juárez EI, Ellis EA, Rodríguez-Luna E. 2015. </span><span style="font-size: x-small;"><span style="font-weight: normal;"><span class="mainTitle">Quantifying the severity of hurricanes on extinction probabilities of a primate population: Insights into “Island” extirpations. American Journal of Primatology 77:786-800.</span></span></span><br />
<br />
<span style="font-size: x-small;">Manson RH, Jardel Pelaez E, Jimenez Espinosa M, et al. 2009. Perturbaciones y desastres naturales: impactos sobre las ecorregiones, la biodiversidad y el bienestar socioeconomico, en: Capital natural de Mexico, vol II: Estado de conservacion y tendecias de cambio. Conabio, Mexico, pp. 131-184. </span><br />
<br />
<span style="font-size: x-small;">Portilla-Ochoa E, Sanchez-Herdandez AI, Hernadez-Meza D. 2006. El impacto de los huracanes en la biodiversidad del estado de Veracruz. In: Inundaciones 2005 en el estado de Veracruz. pp. 101-119. Universidad Vercruzana, Veracruz Mexico. </span>Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.com0tag:blogger.com,1999:blog-7078978091325512838.post-28596900740179909652015-07-07T14:29:00.002-04:002015-07-07T14:30:08.979-04:00A look inside an ancient primate's brain yields surprisesFifteen million years ago the earliest known member of the subfamily <b>cercopithecine</b> roamed the planet. <i>Victoriapithecus</i> is the most ancient old world monkey scientists have discovered to date. This <b>frugivorous</b>
primate was found on an island in Lake Victoria (Benefit, 1999). What
we know about this species is a result of one fossil, a skull. A recent
study by Gonzales and colleagues studied the inside of this monkey's
skull (also called an <b>endocast</b>) to learn more about the brain structure of <i>Victoriapithecus</i>.<br />
<br />
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; text-align: left;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjODtX1f4XkVKT46hTTbTK2EIlekGSZXDK687uG1XbRjbvcfj0UWND1A7KtXuxuwZ8ziv461S360xmwbkAp1TQ-CbbVi9E3PhfITi_kPWPy08ZEU_8W4ho5TnR7wzkzp80X0RS_s_xigXk/s1600/Screen+Shot+2015-07-06+at+9.38.28+PM.png" style="clear: left; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="200" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjODtX1f4XkVKT46hTTbTK2EIlekGSZXDK687uG1XbRjbvcfj0UWND1A7KtXuxuwZ8ziv461S360xmwbkAp1TQ-CbbVi9E3PhfITi_kPWPy08ZEU_8W4ho5TnR7wzkzp80X0RS_s_xigXk/s200/Screen+Shot+2015-07-06+at+9.38.28+PM.png" width="191" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Endocast of <i>A. sediba</i>, Photo credit: <a href="https://en.wikipedia.org/wiki/Paleoneurology#/media/File:Endocast_of_australopithecus_sediba.jpg" target="_blank">Lee Berger</a></td></tr>
</tbody></table>
Using high-resolution X-ray imaging, researchers were able to create a 3D model of what <i>Victoriapithecus</i>'s brain looked like. The results were surprising. At only 35.6<span class="mb"><span class="mb"> </span></span>cm<sup>3</sup>,
this monkey had a brain about the size of a plum: small when compared
to the animal's body size. Most primates this size have a brain that's
about the size of an orange.<br />
<br />
The olfactory bulb, the
part of the brain in which sense of smell is processed, was three times
larger than expected. It was along the lower end of what we see for <b>strepsirrhines</b>, a group of primates with a greater reliance on sense of smell when compared to <b>haplorhines</b> (new and old world monkeys, tarsiers, and apes).<br />
<br />
Despite having a small brain and a greater reliance on smell, characteristics typically seen in the so-called lower primates, there is more to <i>Victoriapithecus </i>than meets the eye. Micro CT scans were able to show the wrinkles and folds in the brain.
Given that this animal had quite a small brain, the numerous ridges and
folds (sulci and gyri) show that this species was complex. <a href="http://thebraingeek.blogspot.com/2012/04/folds-of-brain.html" target="_blank">Folds on the brain are generally linked to greater intelligence</a>. The organization of <i>Victoriapithecus</i>'s
brain and the sulci and gyri are what we see in present-day
cercopithecines. Thus, it looks like a having a large brain is not a
prerequisite for having a complex brain.<br />
<br />
<br />
<br />
Links of interest:<br />
<a href="http://www.livescience.com/28209-brain-organization-key-to-intelligence.html" target="_blank">Brain size and evolution</a><br />
<a href="http://www.sciencedaily.com/releases/2013/10/131008102559.htm" target="_blank">Developmental pattern of primate brains</a><br />
<a href="http://news.sciencemag.org/evolution/2013/10/did-snakes-help-build-primate-brain" target="_blank">How snakes may have influenced primate brain evolution </a><br />
<br />
<br />
<span style="font-size: x-small;">Literature cited:</span><br />
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;"><span class="vcard author"><span class="fn">Benefit, B. R.</span></span> <span class="title"><i>Victoriapithecus</i>: the key to Old World monkey and catarrhine origins</span>. <span class="source-title">Evol. Anthropol.</span> <span class="volume">7</span>, <span class="start-page">155</span>–<span class="end-page">174</span> (<span class="year">1999</span>). </span><br />
<br />
<span style="font-size: x-small;">Gonzales, L., Benefit, B., McCrossin, M., Spoor, F. Cerebral complexity preceded enlarged brain size and reduced olfactory bulbs in Old World monkeys. <i>Nature Communications</i>, 2015; 6: 7580 DOI: <a href="http://dx.doi.org/10.1038/ncomms8580" rel="nofollow" target="_blank">10.1038/ncomms8580</a> </span><br />
<span class="st" data-hveid="36"></span>Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.com0tag:blogger.com,1999:blog-7078978091325512838.post-23786144694669951602015-06-30T08:27:00.000-04:002015-06-30T09:36:30.795-04:00Olive baboons can be democratic when it comes to troop movementOlive baboons (<i>Papio anubis</i>) live in a world where social rank matters. They live in troops that can have over one hundred individuals, with females remaining in their<b> natal group</b> and males dispersing. Males are dominant over females but females have a strict linear dominance hierarchy, meaning who your mother is matters. A lot. Related females groom each other and have each others backs in agonistic meetings. <br />
<br />
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: left; margin-right: 1em; text-align: left;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi8MoD-YJLCQcyBdrCtJWckXIFgL43YZ-kVV7UHiaV19NSgg6gWiqrG06YhHgIErxSQIIklLHcsdOj1HV0Cx4_nBrl4RuzK21-dqx4ZZoFXp6nzlERyVmPsURNzdsTWwTTRNxXHdT_94qk/s1600/Screen+Shot+2015-06-29+at+9.37.17+PM.png" imageanchor="1" style="clear: left; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi8MoD-YJLCQcyBdrCtJWckXIFgL43YZ-kVV7UHiaV19NSgg6gWiqrG06YhHgIErxSQIIklLHcsdOj1HV0Cx4_nBrl4RuzK21-dqx4ZZoFXp6nzlERyVmPsURNzdsTWwTTRNxXHdT_94qk/s320/Screen+Shot+2015-06-29+at+9.37.17+PM.png" width="288" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Photo credit: <a href="https://commons.wikimedia.org/wiki/File:Olive_Baboon_Papio_anubis_in_Tanzania_3066_Nevit.jpg" target="_blank">Nevit Dilmen</a></td></tr>
</tbody></table>
A new study out in <i>Science</i> by Strandburg-Peshkin and colleagues shows that, much to everyone's surprise, olive baboons are democratic when it comes to troop movement. Yep, these primates, which can be known for their aggression (just look at those canines), don't bully when it comes to choosing where to go.<br />
<br />
What we'd expect in a primate with such a strict social system is that the group would go where dominant individuals want to go. Those lower on the social totem pole aren't going to act against a more dominant individual's decision nor are they going to attempt to make these decisions themselves. However, using GPS technology, researchers found that the troop tends to go where multiple initiators want to go and individuals who move in a directed manner are more likely to be followed.<br />
<br />
When two groups within a troop are moving in different
directions, the larger group is more likely to win, and this
likelihood grows as the difference in size between the two groups of initiators grows. The authors failed to clarify if, of those decisions with multiple initiators, the number of dominant individuals within groups of initiators made a difference. I'd like to know if five low-ranking individuals could top two high-ranking individuals, when determining which direction to go. Does social rank really have no effect? I'm not sure I'm entirely convinced that it doesn't, but I also don't study baboons.<br />
<br />
Now, this study was conducted by studying 33 out of 46 members of one baboon troop over nine days, so it'd be interesting to see if results differ in other troops, in troops of differing sizes, or during different times of the year (for example, when food resources are low). It'd also be interesting to see if this finding holds true for other species of baboons. For example, previous research has shown chacma baboons (<i>Papio ursinus</i>) do pay attention to social relations when deciding which patches of food to target (Marshall et al., 2012).<br />
<br />
Food for thought:<br />
Strandburg-Peshkin and colleagues didn't find any differences based on sex when it came to an individual initiating troop movement. Why is this surprising?<br />
Why might this system (in which the troop is democratic in deciding where to go) be adaptive to baboons? When might it not be?<br />
<br />
Links of potential interest:<br />
<a href="http://pin.primate.wisc.edu/factsheets/entry/olive_baboon/behav" target="_blank">Olive baboon behavior and social organization </a><br />
<a href="http://www.sciencedaily.com/releases/2012/09/120913203917.htm" target="_blank">Chacma baboon study</a><br />
<br />
<br />
<span style="font-size: x-small;">Literature cited:</span><br />
<span style="font-size: x-small;">Ariana Strandburg-Peshkin, Damien R. Farine, Iain D. Couzin, and Margaret C. Crofoot. Shared decision-making drives collective movement in wild baboons. <i>Science</i>, 19 June 2015 DOI: <a href="http://dx.doi.org/10.1126/science.aaa5099" rel="nofollow" target="_blank">10.1126/science.aaa5099</a></span><br />
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;">Harry H. Marshall, Alecia J. Carter, Tim Coulson, J. Marcus Rowcliffe, Guy Cowlishaw. Exploring Foraging Decisions in a Social Primate Using Discrete-Choice Models. <i>The American Naturalist</i>, 2012; 180 (4): 481 DOI: <a href="http://dx.doi.org/10.1086/667587" rel="nofollow" target="_blank">10.1086/667587</a></span><br />
<br />Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.com0tag:blogger.com,1999:blog-7078978091325512838.post-88984252238975092412015-06-25T08:56:00.001-04:002015-06-25T08:56:06.388-04:00Potential innate difference in tool use between chimps and bonobos<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; margin-left: 1em; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiLxvxwHLS25nUUELyuogzQRCB1ZuebSz7x3GhjycdLFrhgtXco_n3CH8m8lYMrT1-iFmiMy-XPVVtQwyqkB3n_SjhRxbjfUib8GA2OsNzXJPfeIpTEVKPI7pDr8RBIh-Ph10yP0VPyomE/s1600/Screen+Shot+2014-12-11+at+12.19.12+PM.png" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="224" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiLxvxwHLS25nUUELyuogzQRCB1ZuebSz7x3GhjycdLFrhgtXco_n3CH8m8lYMrT1-iFmiMy-XPVVtQwyqkB3n_SjhRxbjfUib8GA2OsNzXJPfeIpTEVKPI7pDr8RBIh-Ph10yP0VPyomE/s320/Screen+Shot+2014-12-11+at+12.19.12+PM.png" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Young chimpanzee. Photo credit <a href="https://www.flickr.com/photos/frauschnatterliese/14146037805/in/photolist-5nPL6-29zXHS-nmDhUW-kFBqi6-3akF4o-pteuBN-9jNQFG-8zMmft-bBR2cs-nQFwSQ-4AetBE-eh2z87-eiu8VH-5YzifQ-7iPDu4-oJfoy2-6tyzJw-aEsaCb-8oWuSc-bCBPgJ-F6XDW-3bm8iT-oNV1W3-izL1zF-os2GPu-ghYNFS-8UuGVA-nnnKhn-4x3fEk-8RyG4Y-arq7n5-oYmXpf-8zQud9-ghZb4w-6MbXGm-fGFd9m-bUmKZ9-6Mc5HE-5p37Y7-4x7geQ-8oZF1j-g6Eimo-7dhFR4-6vD1wG-adxHvw-4QnzEt-8PxP51-7ofHNA-dy9Ao2-ny39cx" target="_blank">Sabine Bresser</a></td></tr>
</tbody></table>
Koops, Furuichi and Hashimoto published a paper recently on the innate ability to use tools in chimpanzees (<i>Pan troglodytes</i>) and bonobos (<i>Pan paniscus</i>). Both species are our closest living relatives, thus providing opportunities to study the evolution of our species and determine what makes humans human. Tool use has long fascinated biological anthropologists, ever since it was first recorded by Jane Goodall at Gombe in 1960.<br />
<br />
The authors tracked both species for three months each and recorded all instances of tool use and all instances they thought had potential for tool usage. Fourteen chimps and sixteen bonobos were studied.<br />
<br />
Koops and her colleagues determined the available opportunities to harvest army ants and termites (insects that required tool use), nut trees and stones available below those nut trees (used to crack open the nuts) at each of the two sites. The authors determined that the opportunities for dipping for termites and/or army ants was present at both sites. Opportunities for nut cracking were available but limited. <br />
<br />
Bonobo young spent more time with their mothers than did chimpanzees. Bonobos also spent more time in close proximity to each other in feeding contexts. Bonobos also had more individuals in close proximity and more social partners than chimpanzees did, thus bonobos had increased opportunities for social learning. Neither ape cracked nuts. Interestingly, bonobos did not fish for termites or army ants whereas chimpanzees did. Both species were more likely to manipulate objects in a resting context than in a feeding context. The most convincing evidence that there is an innate difference between these two species is that chimpanzees less than one year old were observed manipulating objects. These young animals have had few opportunities for social learning, the authors argue, thus their object manipulation is intrinsic.<br />
<br />
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh9G7r9IavuJ0NWUE3nbx8WZYqv8MEL_8HKPXifVi7WN1NFmDPWzhZql4Y55U9wxNLbUszSrJJTXW5fsTDmRNUu5ARN8VLVuQop4fRFPQg556T8ZtKEhV9E4S8R11OeF0P09ilgw7ScqfE/s1600/Screen+Shot+2015-01-24+at+11.23.07+PM.png" imageanchor="1" style="clear: left; float: left; margin-bottom: 1em; margin-right: 1em;"><img border="0" height="240" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh9G7r9IavuJ0NWUE3nbx8WZYqv8MEL_8HKPXifVi7WN1NFmDPWzhZql4Y55U9wxNLbUszSrJJTXW5fsTDmRNUu5ARN8VLVuQop4fRFPQg556T8ZtKEhV9E4S8R11OeF0P09ilgw7ScqfE/s320/Screen+Shot+2015-01-24+at+11.23.07+PM.png" width="320" /></a>I'd like to see this study replicated and expanded. Studying each species for only three months doesn't yield a very large amount of data when we're talking about behavioral studies. The more data the better, and given that chimpanzees and bonobos don't reach maturity until around age eight, it's possible study these young apes for more than a few months. I also think it'd be ideal to see this study replicated across numerous sites, incorporating different habitats. Because neither species cracked nuts, we're really only talking about using tools to fish for ants and termites. Given the <a href="https://en.wikipedia.org/wiki/Tool_use_by_animals" target="_blank">diverse tool use we see in animals</a>, I wonder if it is a bit premature to declare that chimps are inherent tool users compared to bonobos given the limits of this study. Nonetheless, Koops and her colleagues certainly made an interesting discovery, and it'll be exciting to see what they discover next, as at least one more publication on this topic appears to be in the works.<br />
<br />
For now, chimps have a more innate propensity to use tools for army ants and termites. In the future, we very well may prove chimpanzees have more of an innate propensity for tool use than bonobos or at least a different type of innate ability to use tools.<br />
<br />
<br />
Links of interest:<br />
<a href="http://letstalkprimates.blogspot.com/2015/06/chimpanzees-understanding-cooking-and.html" target="_blank">Chimps that cook</a><br />
<a href="http://letstalkprimates.blogspot.com/2015/04/female-chimps-are-more-likely-than.html" target="_blank">Female chimps more likely to use tools when hunting </a><br />
<a href="http://letstalkprimates.blogspot.com/2015/01/are-famous-sex-loving-bonobos-really.html" target="_blank">Are bonobos more peaceful than chimps?</a><br />
<a href="http://letstalkprimates.blogspot.com/2014/12/how-human-are-chimps-differences-and.html" target="_blank">How human are chimps?</a><br />
<br />
<span style="font-size: x-small;">Literature cited:</span><br />
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;">Kathelijne Koops, Takeshi Furuichi and Chie Hashimoto. Chimpanzees and bonobos differ in intrinsic motivation for tool use. <i>Scientific Reports</i>, 2015 DOI: <a href="http://dx.doi.org/10.1038/srep11356" rel="nofollow" target="_blank">10.1038/srep11356</a></span>Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.com0tag:blogger.com,1999:blog-7078978091325512838.post-65628333958524657892015-06-10T09:22:00.001-04:002015-06-10T09:30:08.476-04:00Chimpanzees understanding cooking and choose to do itWe can add another skill to the long list of what chimpanzees are able to do: cook. A study was published last week on a series of cooking related experiments done with semi-free-ranging chimpanzees from the <a href="http://www.janegoodall.org/programs/tchimpounga-chimpanzee-rehabilitation-center" target="_blank">Tchimpounga Chimpanzee Sanctuary</a> and the results are fascinating. This was a very cool series of experiments!<br />
<br />
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiWKnY0jLXK8a4bxpC2eFYu6kN7BJsbmAIMhkbC1t7siQNMtdqwxdN1E0MXyArZ5N5txbCX9jxZy17tar7JbY7vHGMLT_ax_BV_-Srpn9IO-vE86GPSGW2yTfer1xyGRPe2dnoBLTrn-D4/s1600/chimp+pant+hoot.png" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img border="0" height="206" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiWKnY0jLXK8a4bxpC2eFYu6kN7BJsbmAIMhkbC1t7siQNMtdqwxdN1E0MXyArZ5N5txbCX9jxZy17tar7JbY7vHGMLT_ax_BV_-Srpn9IO-vE86GPSGW2yTfer1xyGRPe2dnoBLTrn-D4/s320/chimp+pant+hoot.png" width="320" /></a>Warneken and Rosati first tested sixteen chimpanzees on whether they would choose to delay and receive a larger portion of food that was either raw or cooked or if they would choose an immediate but smaller portion of food. The chimps chose to wait (and thus consume a larger quantity) 60% and 84.4% of the time for the raw and cooked food respectively, showing that the chimps are more willing to suffer the delay to consume a cooked item than a raw item. This finding isn't surprising, as any zookeeper can tell you apes prefer many cooked foods to raw ones. It gets much better though.<br />
<br />
The next experiment tested whether or not the chimpanzees understood cooking. Subjects chose between a container that "cooked" the item and bowl that did not cook the item. Raw food was placed in both the container and the bowl, the experimenter shook both of them, but only the container resulted in cooked food. The chimps chose the container with cooked food over 87% of the time. The next test was to determine whether chimps would immediately consume a piece of available food or place it in either the cooking device or the bowl (that didn't cook the item). Thirteen out of twenty-one chimps chose the cooking device at least one time. Chimps that chose a device chose the cooking device more than 80% of the time. The next experiment gave the chimps carrots, which they had not seen in the context of the cooking devices, and the chimps chose to cook the carrots more often than not. When given non-edible items, the chimps didn't try to cook those. All of these experiments point to chimps having the ability to comprehend cooking on a very basic level. They're not cooking everything and they're choosing to cook items that make sense.<br />
<br />
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: left; margin-right: 1em; text-align: left;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhfBTg3ap2q1GVzMWYjdNHYI1xZ1Oyq4n6tkLIodIPw4oVqOvFse26QFXV_T556ayBMeNCz1zf5aHVH7AXSZY09n42wZCwBj_R3sOEpsY2wp0mXU4TJQfcOIdSAT1bTn9DdcUi7ZxDeE1E/s1600/Screen+Shot+2014-11-14+at+9.36.00+PM.png" imageanchor="1" style="clear: left; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="229" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhfBTg3ap2q1GVzMWYjdNHYI1xZ1Oyq4n6tkLIodIPw4oVqOvFse26QFXV_T556ayBMeNCz1zf5aHVH7AXSZY09n42wZCwBj_R3sOEpsY2wp0mXU4TJQfcOIdSAT1bTn9DdcUi7ZxDeE1E/s320/Screen+Shot+2014-11-14+at+9.36.00+PM.png" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Photo credit:<a href="https://www.flickr.com/photos/harlequeen/7913354128/" target="_blank"> Neil McIntosh</a></td></tr>
</tbody></table>
Warneken and Rosati then upped the stakes and placed the cooking device further away to determine if the subjects would travel in order to cook their food. All but one of the thirteen chimps successfully transported food to the cooking device that was far away at least once. And when the cooking device was far away, chimps still chose to visit it 60% of the time.<br />
<br />
This study is impressive because the sample size is quite robust for a primate cognition study. (Usually you get sample sizes that are smaller because zoos don't have the ability to house so many animals). Because this study was done with semi-free-ranging chimps at a rehabilitation center, the sample size is larger. We're not talking about one ape that knows some sign language, although that's amazing too. We're talking about roughly thirteen individual chimps that are now probably wondering where that magical container went that cooked all of their food.<br />
<br />
Links potentially of interest:<br />
<a href="https://www.youtube.com/watch?v=qOuv4U7u1j0" target="_blank">BBC Horizon Video-Did cooking make us human?</a><br />
<a href="http://letstalkprimates.blogspot.com/2014/12/how-human-are-chimps-differences-and.html" target="_blank">How human are chimps?</a><br />
<br />
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;"><br /></span>
<span style="font-size: x-small;">Literature cited:</span><br />
<span style="font-size: x-small;">Felix Warneken, Alexandra G. Rosati. <b>Cognitive capacities for cooking in chimpanzees</b>. <i>Proceedings of the Royal Society B.</i>, June 2015 DOI: <a href="http://dx.doi.org/10.1098/rspb.2015.0229" rel="nofollow" target="_blank">10.1098/rspb.2015.0229</a></span>Katehttp://www.blogger.com/profile/07398749795445318185noreply@blogger.com0