Syndicate content

Archive - Mar 5, 2013

Ancient DNA Solves Mystery of the Enigmatic Falkland Islands Wolf

University of Adelaide researchers in Australia have found the answer to one of natural history's most intriguing puzzles – the origins of the now extinct Falkland Islands wolf and how it came to be the only land-based mammal on the isolated islands – 460 km from the nearest land, Argentina. Previous theories have suggested the wolf somehow rafted on ice or vegetation, crossed via a now-submerged land bridge, or was even semi-domesticated and transported by early South American humans. The 320-year-old mystery was first recorded by early British explorers in 1690 and raised again by Charles Darwin following his encounter with the famously tame species on his Beagle voyage in 1834. Researchers from the University's Australian Centre for Ancient DNA (ACAD) extracted tiny pieces of tissue from the skull of a specimen collected personally by Darwin. They also used samples from a previously unknown specimen, which was recently re-discovered as a stuffed exhibit in the attic of the Otago Museum in New Zealand. The findings were published online on March 5, 2013 in Nature Communications and concluded that, unlike what had been suggested by earlier theories, the Falkland Islands wolf (Dusicyon australis) only became isolated about 16,000 years ago around the peak of the last glacial period. "Previous studies used ancient DNA from museum specimens to suggest that the Falkland Islands wolf diverged genetically from its closest living relative, the South American maned wolf (Chrysocyon brachyurus) around seven million years ago. As a result, they estimated that the wolf colonized the islands about 330,000 years ago by unknown means," says Associate Professor Jeremy Austin, Deputy Director of ACAD and co-lead author with Dr. Julien Soubrier.

3.5 Million-Year-Old Fossil of Extinct Giant Camel Found in Arctic

A research team led by the Canadian Museum of Nature has identified the first evidence for an extinct giant camel in Canada's High Arctic. The discovery is based on 30 fossil fragments of a leg bone found on Ellesmere Island, Nunavut, part of the Canadian Arctic Archipelago, and represents the most northerly record for early camels, whose ancestors are known to have originated in North America some 45 million years ago. The fossils were collected over three summer field seasons (2006, 2008, and 2010) and are about three and a half million years old, dating from the mid-Pliocene Epoch. Other fossil finds at the site suggest this High Arctic camel lived in a boreal-type forest environment, during a global warm phase on the planet. The research, by Natalia Rybczynski, Ph.D., and co-authors including John Gosse, Ph.D. (at Dalhousie University, Halifax, Nova Scotia), and Mike Buckley, Ph.D. (at the University of Manchester, UK), was described online on March 5, 2013 in an open-access article in Nature Communications. "This is an important discovery because it provides the first evidence of camels living in the High Arctic region," explains Dr. Rybczynski, a vertebrate palaeontologist with the Canadian Museum of Nature, who has led numerous field expeditions in Canada's Arctic. "It extends the previous range of camels in North America northward by about 1200 km, and suggests that the lineage that gave rise to modern camels may have been originally adapted to living in an Arctic forest environment." The camel bones were collected from a steep slope at the Fyles Leaf Bed site, a sandy deposit near Strathcona Fiord on Ellesmere Island. Fossils of leaves, wood, and other plant material have been found at this site, but the camel is the first mammal recovered.