Young Kissing Girls

Biology and evolution
Anthropologists have not reached a conclusion as to whether kissing is learned or a behavior from instinct. It may be related to grooming behavior also seen between other animals, or arising as a result of mothers premasticating food for their children. Non-human primates also exhibit kissing behavior. Dogs, cats, birds and other animals display licking and grooming behavior among themselves, but also towards humans or other species. This is sometimes interpreted by observers as a type of kissing.