Male gorillas symbolize power, but there are also females who are superior to men

When female mountain gorillas live in a group with multiple males, an adult female gorilla is usually dominant over one of the adult males. This is striking because male gorilla groups are about twice as large as female gorilla groups. The researchers published this result of 25 years of observations in four gorilla groups in Rwanda (with a total of 32 females and 24 males) this week in Current Biology .

Precisely because female power was found in a species still considered "the most prominent example of absolute male power," researchers Nikolaos Smit and Martha Robbins (Max Planck Institute, Leipzig) call their finding a blow to the old patriarchal cliché that male power is self-evident due to physical strength. They also point out that a similar difference in physical strength exists between males and females in chimpanzees and bonobos, while in the latter, females are completely dominant.

The alpha male, who rules over his exclusive harem of females in gorillas—often with a few other males in the margins—is always at the top of the gorilla hierarchy, above all other males and females. But by no means are all other males above all females. Young and older adult males, in particular, sometimes step aside for a particular female, or let her go first when eating rotten wood. Gorillas eat primarily leaves, and no one ever needs to give way to another; leaves are everywhere. But when a tasty piece of rotten wood is found, that's a different story.

Endangered primates

On average, 28 percent of such confrontations between a non-alpha male and a woman end in the woman's favor, Smit and Robbins found in their analyses.

"A wonderful and important study," responds psychologist and primate expert Mariska Kret (Leiden University). This is especially true because the research spans 25 years. "This isn't a simple experiment, but long-term, intensive fieldwork." Fieldwork is no longer a given, says Kret, due to funding issues and, more tragically, the endangered status of primates in the wild.

Kret calls the way women became dominant over men "particularly fascinating." "Not through sexual barter, as was previously thought, but through support from the alpha males, and that support, in turn, depended on the social relationship between them." Social power is stronger here than physical power.

Kret points out that the number of interactions studied between females and males is quite small: 1,169 interactions involving avoidance or displacement, over 25 years. "Most interactions occurred between females and alpha males – with the females winning less than 1 percent of the time (6 out of 889). Against non-alpha males, they won 28 percent of the interactions (79 out of 280). All in all, the power of female gorillas appears to be limited – but not absent."