In an effort to settle the debate about the origin of dog domestication, a technique that uses 3-D scans of fossils is helping researchers determine the difference between dogs and wolves.
In the ongoing debate, one camp believes dogs were domesticated in the Paleolithic age (more than 17,000 years ago), when humans were hunter-gatherers. The other camp believes domestication occurred in the Neolithic age (17,000 to 7,000 years ago), when humans first established agriculture and civilizations.
Abby Grace Drake, a senior lecturer in the Department of Ecology and Evolutionary Biology, and her colleagues have been analyzing 3-D scans of ancient fossil canid mandibles to determine whether they belong to dogs or wolves. The answer, they find, is not so simple.
The researchers found that in the early stages of domestication, the skull changed shape but evolution of the mandible lagged behind and did not co-evolve with the skull. Their study is reported in the Aug. 25 issue of the journal Scientific Reports.
“A lot of the fossil evidence for the date of dog domestication is based on morphological [structural] analysis of mandibles,” said Drake, the paper’s first author. Robert Losey, an anthropologist at the University of Alberta, Canada, is a senior co-author of the paper. “Our study shows that when you measure modern dog mandibles and wolf mandibles using 3-D measurements you can distinguish them, and yet when we looked at these fossil mandibles, they don’t look like dogs or wolves.”
Wolves have fairly straight mandibles while dog mandibles are curved, structural features that become evident in a 3-D scan. In a proof of principle, when analyzing the 3-D structures of mandibles of modern dogs, Drake and colleagues correctly classified 99.5 percent of the samples as being dog or wolf.
This article originally appeared in the Cornell Chronicle.