Fig. 7.

A different patterning of skew in polygynous human populations and polygynous nonhuman mammals. Points represent posterior means, and lines represent 89% credible regions. The dashed vertical line at M^* = 0 indicates that reproduction is neither positively skewed nor more equal than would be expected by a random model. Male reproductive skew in polygynous humans is substantially lower than in polygynous nonhuman mammals: The contrast is −0.59 (89%CI: −0.87, −0.32). Female skew is also higher in polygynous human populations than in polygynous nonhuman mammals: The contrast is 0.2 (89%CI: −0.05, 0.43). Sex differences in skew are therefore much lower in polygynous human populations than in polygynous nonhuman mammals: The contrast is −0.80 (89%CI: −1.03, −0.53). Sample sizes: N = 14 polygynous human populations and N = 41 polygynous nonhuman mammal species.