9,000 years ago, the hunter-gatherers of the Zhokov Island survived frigid temperatures in animal-skin tents, some 500 kilometres north of Russian mainland. These people successfully hunted large numbers of polar bears without any firearms. Recent research has also shown that they may have been the first humans to ever breed dogs for a particular purpose, pulling sleds.
     The research was done by Melinda Zeder, an archaeozoologist at the Smithsonian Institution National Museum of Natural History in Washington D.C. She believes that the evidence of breeding may give an indication as to why ancient populations originally domesticated dogs. As Angela Perri, a zooarchaeologist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, notes "It fills in a missing piece of the puzzle of early human-dog relationships, and even domestication itself."
     Like many areas in Europe the Zhokov Island was once connected to modern Siberian before the sea rose. In this area the Zhokhovians not only hunted polar bears, but also reindeer hundreds of kilometres across vast plains. Vladimir Pitulko, an archaeologist at the Russian Academy of Sceinces in St. Petersburg supports the theory of dogs being bred for sleds, as he notes "They needed a means of transportation." Pitulko has been excavating Zhokov Island since 1989, finding both bog bones and wooden sled remains, but it was unclear whether the dogs were bred for sledding.
     With the help of Aleksey Kasparov, an archaeologist at the same institute as Pitulko, they were able to determine that the bones were indeed canine in nature, though one appeared to be a wolf-dog hybrid. The Zhokhovian dogs were "reconstructed" from fossil bones of 11 individuals and were determined to weigh between 16 and 25 kilograms and most closely resemble modern Siberian Huskies. The wolf-dog Hybrid weighed about 29 kilograms and may have more closely resembled an Alaskan Malamute. Pitulko notes that dogs of this size are big enough to pull sleds without overheating like larger dogs. His theory is that they may have bred smaller dogs for pulling sleds and larger ones to hunt the polar bears, "They were clearly shaping these animals to do something special."
     The reason for domestication and eventual breeding of dogs has been discussed for some time. While scientists do not agree on when the domestication of dogs happened, it has been suggested that it started at least 15,000 years ago. This fits well with climate changes leading to less large game, such as mammoths, and more small game like reindeer. Here dogs could help hunt the smaller prey or even provide means for ancient peoples to track them.
     The team will reveal the full results in the next Journal of Archaeological Science: Reports.

Edited from Science Mag 26 May 2017