A longstanding evolutionary riddle has now been solved by sequencing protein found in the fossils of two strange extinct South American mammals.
Macrauchenia patachonica and Toxodon platensis were two mammals exhibiting some mosaic features which made them difficult to place in the tree of life. Going all the way back to Darwin, scientists couldn't figure out whether they were related to horses, elephants or belonged to altogether new groups. South American mammals from the Pleistocene were just weird.
Researchers from the American Museum of Natural History and the Natural History Museum in London set out to solve this puzzle by analyzing organic remains from the two animal's bones. They couldn't do this with DNA because it degrades rapidly over time, especially in warmer climates like those of South America. So they went looking for proteins and actually found some.