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For ancient mammalian megafauna—from brown bears to bison and more—death was something of a boy’s club. At least that’s what you might conclude from the vaults of natural history museums around the world, where the majority of fossilized mammal specimens come from males.
This has less to do with misogyny than with prehistoric herd distributions, sex-specific causes of death, and a slew of other factors that influenced where and how large mammals tended to die, according to a study published September 3 in Proceedings of the National Academy of Sciences.
Researchers from the University of Adelaide in Australia first identified this strange trend after analyzing ancient DNA in specimens in their own collection, according to Graham Gower, a genomic programmer and a coauthor of the study. There are a few ways to sex an ancient bone. If you’re lucky enough to have a whole bone, such as a skull, the size, shape, and dimensions might differ between male and female. In the case of fragments, researchers might have to dig into DNA for the number of X-chromosome sequences, Gower says. But usable DNA is scarce in most specimens that old. From approximately 20,000 samples, Gower says, the researchers got usable DNA from 5 percent.
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Woolly mammoths in a mural at the American Museum of Natural History in New York. Source: Charles R. Knight / Public Domain.
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