Dogs may have been domesticated much earlier than previously thought, perhaps by initially scavenging with humans. According to research published this week in Nature Communications, this large common history has resulted in dogs and humans evolving together for the last 32,000 years.
Ya-Ping Zhang and colleagues performed whole-genome sequencing of grey wolves, Chinese indigenous dogs and domesticated dogs of different breeds. While wolves are known to be the ancestors of dogs, native dogs of South China are likely the most primitive form of dogs and may represent the product of the first-stage of domestication. The team found a general trend of decreasing diversity from wolves to Chinese indigenous dogs to dog breeds, and found 311 genes that were under strong positive selection during domestication. Those genes have remained in the genome of dogs from the origin of domestication to the current day and give specific evolutionary advantages. Surprisingly, the list of genes under positive selection overlaps extensively with those genes that have been selected over the course of human evolution and relate to digestion, metabolism, neurological processes and cancer.
These results represent evidence that genes positively selected during dog domestication show extensive parallels with human analogue genes.