A kiss, whether stolen away or done in public with gusto, can be naughty or nice. Maybe it's the movies - Sleepless in Seattle, Slumdog Millionaire, When Harry Met Sally, and yes, I know two of these star Meg Ryan - that have convinced us that a big, dramatic kiss is the only thing to do when love takes over.
Brindle and her colleagues, Catherine Talbot of the Florida Institute of Technology and Stuart West of Oxford, wanted to evaluate kissing from an evolutionary perspective. So they searched through past studies for modern examples of primates smooching, defined rather unromantically as non-agonistic interaction involving directed, intraspecific, oral-oral contact with some movement of the lips/mouthparts and no food transfer. They found that just like humans, great apes kiss for a variety of reasons, from conveying sexual desire to indicating friendly, affectionate feelings.
The findings, published on Wednesday in the journal Evolution and Human Behavior, reveal that, far from being a recent human cultural invention, kissing is an ancient trait deeply rooted in our biology. This is the first time anyone has taken a broad evolutionary lens to examine kissing. Our findings add to a growing body of work highlighting the remarkable diversity of sexual behaviors exhibited by our primate cousins, said Matilda Brindle, lead author of the study and an evolutionary biologist in the Department of Biology at Oxford, in a statement.