Humans breed dogs for certain traits, some for herding, others for tracking and some for retrieving game.

A new study looking at dogs’ brain scans, shows that humans have changed the shape of their brain.

Erin Hecht, a neuroscientist studying dog cognition at Harvard University said: “Brain anatomy varies across dog breeds.”

Some variation is caused by “selective breeding for particular behaviors like hunting, herding and guarding.” According to Business Insider, Hecht said this change means humans should be responsible with how they treat animals.