Modern Dog Breeds Have Bigger Brains Due to Urbanization

Modern dog breeds, genetically farther from wolves, have relatively larger brain sizes compared to ancient breeds, likely influenced by urbanization and a more complex social environment. Despite domestication generally leading to a decrease in brain size, researchers found that the more a dog breed is genetically distant from wolves, the larger its relative brain size becomes. The increase in brain size is not related to the specific roles or life history characteristics of the breeds. This study provides new insight into the rapid evolution and diversity within the dog species, possibly due to their adaptation to human environments and social complexity.