Males Aren t Larger Than Females in Most Mammalian Species | Scientific American

In The Descent of Man, Charles Darwin posits that in most species of mammals, males are larger than females. Although Darwin did not cite evidence to back up this claim, his view on sexual size dimorphism was readily accepted as fact, and it still dominates today.

But Darwin, in this case, seems to have been wrong. An analysis of 429 mammalian species published in Nature Communications reveals that just 45 percent feature males that are larger than females. Nearly an equal number of species, 39 percent, have sexes that are about the same size. And in 16 percent of species, females are larger than males.

There s been this really strong inertia toward the larger male narrative, but it was just based on Darwin s hand-wavy statement, and the evidence doesn t really support it, says the study s lead author Kaia Tombak, a postdoctoral evolutionary biologist at Purdue University. That this narrative has endured for so long may reflect Western societal biases that tend to look at issues through a male lens.

via www.scientificamerican.com

As LWJ often says, dynamite comes in small packages.

Also, this study appears to look just at the number of species. Perhaps we’re talking about a bunch of rodents that have larger females. Males would then still have the glamorous species. Moreover if the score is 45/39/16 percents for M/F/tied respectively, size-wise, I’d still give the prize to males.