The Friday File: In a new study, researchers find dog breed is responsible for only 9% of variations in dog behavior. Physical traits were more closely linked to breed type with ear shape having the closest connection. Howling was the behavioral trait most connected to breed particularly in beagles, bloodhounds, and Siberian huskies. Genes for most behaviors (friendliness, cuddling) date before the 19th century when most modern breeds were created.