Dogs and wolves are genetically similar enough to reproduce, yet dog behavior has evolved, adapting to an anthropogenic niche. Major changes in dog behavior include ease in forming interspecies social bonds; as well as a reduction of hazard-avoidance behaviors. Both changes are largely shaped by experiences during the primary critical period of socialization, when the developing brain is highly susceptible to environmental influence. In wolves, this interval starts and ends two weeks earlier than in dogs. As a result, wolves experience a narrower set of sensory information than do dogs, even in identical environments. We hypothesize this shift in development may arise through a small number of genomic regulatory or coding changes, with major effects on adult behavior. To find these changes, we are conducting a pilot genome-wide study of 71 wolf-dog hybrids with a wide range of ancestry, allowing us to study the association of behavior and genetics in a single population with varying behavioral phenotypes. We collected DNA and assessed each subject’s response to novelty. Using whole genome association and admixture mapping, we have identified regions associated with differences in reaction to novelty, and enriched for genes implicated in autism, a syndrome thought to result from disregulation during the primary critical period of socialization. By combining ethological and genomic techniques with the unique ancestry of the hybrid population, we gain new insight into the evolution of dogs.