Jacinta C. Beehner

The overarching theme of my research has been to identify situations where male and female reproduction come into conflict with one another. When animals sexually reproduce, one sex generally invests more in the production and care of offspring than another. In mammalian species, this is typically the female, due to the high costs of gestation and lactation. Such an imbalance leads to conflicting reproductive strategies for males and females – a theoretical framework known as sexual conflict. In addition to identifying these situations across mammals, I also want to understand how this conflict plays out in terms of physiology and behavior. The bulk of my research program is focused on female counterstrategies to male coercive reproductive tactics, such as infanticide. This includes strategies such as male-mediated pregnancy termination (for pregnant females) and deceptive fertility (for lactating females). Ultimately, my goal is to incorporate these strategies into evolutionary models that are able to predict social systems across mammals.

I tackle this research from an evolutionary perspective while utilizing a comparative (i.e., examining the same research question across different species) and mechanistic (i.e., assessing fecal hormone profiles) approach. My study subjects have been non-human primates (baboons, geladas, and – recently added – capuchins) living in their natural environments in Africa and the Americas. These primates provide ideal study subjects because they are highly social animals with a high degree of reproductive skew. In other words, not all animals get to reproduce equally (the primary currency for evolution), and thus my main line of inquiry is to determine why some animals are more successful at reproduction than others.