for a variety of species, size doesn’t seem to correlate reliably with which sex is dominant. The African water chevrotain, which is a type of deer, and many small antelopes, for example, have larger females who aren’t dominant. Meanwhile, the Chinese hamster, ring-tailed lemur, and pygmy marmoset all have smaller females that dominate the males. Bonobo females, too, are generally smaller than the males. “Their larger size is balanced by the fact that females cooperate against males, whereas males seldom cooperate against females,” notes Barbara Smuts.
