Protein Sequencing Solves Darwinian Mystery of "Strange" South American Mammals

Macrauchenia patachonica
© Peter Schouten

Scientists have resolved pieces of a nearly 200-year-old evolutionary puzzle surrounding the group of mammals that Charles Darwin called the “strangest animals ever discovered.” New research led by the American Museum of Natural History, the Natural History Museum in London, and the University of York shows that South America’s so- called “native ungulates”—the last of which disappeared only 10,000 years ago—are actually related to mammals like horses rather than elephants and other species with ancient evolutionary ties to Africa as some taxonomists have maintained. Published today in the journal Nature, the findings are based on fossil protein sequences, which allow researchers to peek back in time up to 10 times farther than they can with DNA.