ARCTIC: When the ancestors of today’s Inuit population crossed into North America from Siberia 2,000 years ago, they had a secret weapon that would help them conquer the notoriously harsh Arctic climate: their dogs. Although dogs were already present in North America, according to a recent study of hundreds of dog and wolf remains, the first Inuit migrants brought their own specialized breed of sled dog with them. These dogs were genetically distinct from and larger and stronger than North American canine populations of the time.