Scientists Pinpoint Origin of Kissing to 20 Million Years Ago, Tracing it Back to Primates
OXFORD, UK – A new study from the University of Oxford suggests that the act of kissing – defined as non-aggressive, non-food-transferring mouth-to-mouth contact – originated approximately 21.5 to 16.9 million years ago among primates. The research, published recently, utilizes evolutionary modeling to pinpoint the timeframe for the emergence of this behaviour, challenging the notion that kissing is uniquely human.
Lead author Matilda Brindle,from the Department of Biology at the University of Oxford,explained the methodology: “Based on these two premises,we employed modeling that allows us to simulate different evolutionary scenarios. Applying the modeling millions of times, we came to the conclusion that the first kiss occurred 21.5 to 16.9 million years ago.”
The study doesn’t attempt to identify who delivered the first kiss, but rather establishes when the behavior likely began. Researchers acknowledge the function of kissing remains open to debate. Some theories suggest it evolved as a way to assess partner quality, while others propose it functions as foreplay, increasing sexual excitement and the likelihood of fertilization.
Brindle notes, “Some people suggest that sexual kissing is a way of establishing the quality and suitability of a partner.But the kiss could also be like foreplay, increasing sexual excitement and, consequently, the chances of fertilization.”
The research also suggests kissing wasn’t solely reserved for romantic encounters. Scientists beleive mouth-to-mouth contact between friends and family members may have served to strengthen social bonds and navigate complex relationships.
Intriguingly, the study proposes that Neanderthals likely engaged in kissing as well, citing shared microbes in their mouths as evidence of saliva exchange. “They probably kissed each other on the mouth,” brindle stated, adding that this aligns with existing evidence of interbreeding between humans and Neanderthals, as evidenced by Neanderthal DNA present in modern human populations. ”But it certainly adds a hint of romanticism to the relationship between humans and Neanderthals.”
Jake Brooker, a great ape specialist at Durham University in the United Kingdom, who was not involved in the study, supports the findings. He points out that kissing behavior is observed in a variety of monkey species, suggesting an even earlier origin in our shared evolutionary past. “customs that we tend to think of as exclusive to humans, like kissing on the mouth, are not just ours,” Brooker told The Guardian. “Just look at other animals more closely.”
