Girl power

Sifakas don’t experience a lot of feeding competition, from what I’ve seen so far, which isn’t surprising given their diet. If any feeding competition between a male and a female were to occur though, I bet you’d be surprised at who would come out on top. The female. Sifakas, like almost all of their primate relatives on Madagascar, have a social system in which females are dominant over males. Meaning the females can and do push the males around when it comes to any sort of feeding competition. It’s an unusual system to be sure, and no one is entirely positive as to how female dominance came to evolve.

Ring-tailed lemur sunning in early morning

One of the main theories is that female dominance evolved in response to the unpredictable environment of Madagascar. Females have feeding priority because it is advantageous for them to be healthy so that they can successfully produce offspring. Remember an earlier post about the term “fitness” in the field of biology? If females aren’t eating enough or are eating poorly, and they’re offspring aren’t surviving, no one’s fitness is increasing. It doesn’t matter if you’re a male or a female: the offspring need to survive. 

Like I said, I haven’t seen a lot of aggression in my time here watching sifakas. There seems to be plenty of leaves and flowers to go around. Every now and then, you will hear a rustle in the trees and some squealing, and it’s usually a female kicking a male out of his spot. Otherwise, everyone seems to get along rather peacefully, eating and sleeping all day long. If you’re a fan of girl power, these primates certainly have it. Other species of lemurs, those with choice food items, may experience higher rates of aggression within the troop, but sifakas are pretty laid back.

Lactating mother, Sarah Louise, with infant

Critical thinking: Can you think of a scenario in which female dominance would be beneficial?

Critical thinking: With unlimited funds and resources, how might you test your hypothesis as to what scenario might make female dominance beneficial?