Ancient Arctic Camels Unearthed

Three-and-a-half million years ago, camels roamed the Arctic. This bizarre pairing of mammal and habitat was deduced by analyzing ancient collagen proteins preserved in bone fragments found by Natalia Rybczynski, a paleontologist with the Canadian Museum of Nature (Nat. Comm., DOI: 10.1038/ncomms2516). When Rybczynski found the bones on Ellsmere Island in Canada’s Arctic, she thought they looked like the lower leg bone of a large mammal but wasn’t sure which one. She asked Michael Buckley from Manchester Institute of Biotechnology, in En­gland, to compare the ancient bone’s collagen protein sequence with those from a variety of known species. The sequence best matched that of modern camels, as well as a camel ancestor from the Yukon, about 1,200 km (745 miles) south of the Arctic Circle. The team also worked with Dalhousie University’s John C. Gosse to date the bones by measuring the radio­active decay of beryllium and aluminum in the layers of sand where the bones were found. Cold temperatures made possible in part the collagen’s remarkable preservation for 3.5 million years. However, when camels lived on Ellsmere Island, Earth was 2–3 °C warmer than it is now, and the Arctic was a forest rather than a frozen landscape.