An ancient bone fragment holds clues How did dogs get to the Americas? An ancient bone fragment holds clues. The history of dogs has been intertwined, since ancient times, with that of the humans who domesticated them. But how far back does that history go in the Americas and which route did dogs use to enter that part of the world? A U.S. National Science Foundation-funded study led by researchers at the University at Buffalo provides insight into these questions. The results show that a bone fragment found in Southeast Alaska belongs to a dog that lived in the region about 10,150 years ago. Scientists say the bone — a piece of a femur — represents the oldest confirmed remains of a domestic dog in the Americas.