Taylor Hersh and a team of European researchers began a study hoping to answer a question: Why do dogs wag their tails? Last week, the researchers published their findings: Humans have probably changed the way dogs' tails wag without realizing it. The researchers suspect that dogs' tail wagging made people happy, so people paid attention to this trait when adopting canine ancestors into their lives and breeding the animals.
The research can shed light on what people thought tens of thousands of years ago, according to researcher Andrea Ravignani.