A new study has determined that farming may have changed the genetic markup of dogs as they evolved into the domesticated companions they are today. According to a study by researchers at Uppsala University in Sweden, the high-starch diets dogs were eating 7,000 years ago while living alongside farmers caused them to create additional genes to help them digest starches, like wheat and millet.
Evolutionary geneticist Erik Axelsson identified in dogs multiple copies of Amy2B, Science explains, a gene that works to digest starches. The modern dogs have has many as 15 times the amount of copies of this gene than wolves, who have only two, the scientists say.
Working with a French paleogeneticist, Axelsson examined DNA from the remains of 13 ancient dogs, ranging from 5,000 to 7,000 years old. Those dogs, the scientists concluded, had eight copies of the gene.
Based on these findings and supporting evidence from a 2016 survey of the genes of wolves and various dog breeds, scientists concluded that dogs developed these extra copies of the gene in order to adapt to the diets of the humans they lived near, specifically to starches as the farming industry grew.