Ancient dog bone may explain how animals first arrived in North America

A fragment of a dog bone found in Alaska that researchers claim is the oldest evidence of domesticated dogs in North America could reveal a timeline of when the animals first arrived in the US.

The fragment of a dog’s femur bone, which is smaller than the size of a coin, was discovered by scientists studying climate changes during the Ice Age in Alaska, according to a press release from the University at Buffalo.

While analysing hundreds of fragments found in Alaska dating back a decade, the researchers discovered that the piece of bone, which they previously predicted was from a bear, contained DNA from a dog that lived around 10,150 years ago.

The research was published in the UK journal, Proceedings of the Royal Society B, on Tuesday, and the authors of the study have claimed that the findings suggest that dogs first migrated to North America around 16,000 years ago.

Dogs are thought to have first been domesticated in Europe between 32,000 and 18,800 years ago before they came to North America with Siberian settlers, according to ABC News.

Researchers came to the conclusion about the first sign of dogs in North America because the DNA analysed from the femur fragment found on the Alaskan coast suggests that it diverged from a Siberian dog as early as 16,700 years ago.

Around that same period, humans are thought to have migrated to North America along a coastal route that includes parts of Alaska, where the fragment was found.

Flavio Augusto da Silva Coelho, one of the paper’s authors and a PhD student in biological sciences at the University at Buffalo, said that the discovery is important as fossil records are incomplete.

He confirmed that the previous earliest discovery of dog bones in the US was found in the Midwest, and claimed that the research supports the theory that dogs first came to North America through the “Northwest Pacific coastal route”.

The lead author of the study, University of Buffalo evolutionary biologist Charlotte Lindqvist, said in the release that the discovery was found by accident and revealed that “this all started out with our interest in how Ice Age climatic changes impacted animals’ survival and movements in this region.”

She added that the research suggests that “Southeast Alaska might have served as an ice-free stopping point of sorts, and now - with our dog - we think that early human migration through the region might be much more important than some previously suspected.”

The timing of when dogs first came to North America is still unclear, but as the new discovery is from the same time period that Europeans first migrated there, the study suggests that “dogs accompanied the first humans that entered the New World.”

The researchers added: “The history of dogs has been intertwined, since ancient times, with that of the humans who domesticated them.”