UPDATE: A groundbreaking study reveals that the act of kissing dates back approximately 21 million years, predating modern humans by millions of years. This startling discovery, published on November 19, 2023, in the journal Evolution and Human Behavior, sheds new light on the evolutionary history of this intimate behavior.
The research, led by Matilda Brindle, an evolutionary biologist at the University of Oxford, indicates that kissing likely began with our shared ancestor with other large apes. The study suggests that even Neanderthals, our closest extinct relatives, engaged in kissing—possibly even with modern humans.
Why does this matter RIGHT NOW? Understanding the origins of kissing can illuminate the complexity of social behaviors in early human relatives and their impact on reproductive success and social bonding. This finding adds to a growing interest in how ancient behaviors shape modern interactions.
The researchers defined kissing as “non-aggressive, mouth-to-mouth contact that did not involve food transfer,” a definition crucial for distinguishing it from other mouth-to-mouth behaviors in the animal kingdom. Using advanced statistical modeling, the team ran simulations 10 million times to confirm their findings, establishing that kissing evolved within the Hominidae family between 21.5 million and 16.9 million years ago.
Despite this significant revelation, experts caution against overestimating its novelty.
“I am not sure that the current study adds anything substantially new to our knowledge of this behavior in Neanderthals,”
stated April Nowell, a Paleolithic archaeologist not involved in the study. However, the research aligns with previous evidence suggesting that Neanderthals and early humans may have shared intimate interactions.
Previous studies, including one from 2017, indicated microbial similarities between Neanderthals and modern humans, hinting at potential kissing interactions. As genetic evidence shows that Homo sapiens and Neanderthals interbred for about 7,000 years, the possibility of kissing during these encounters emerges as a fascinating area for further exploration.
The origins of kissing remain complex. Researchers speculate that this behavior might have evolved from the nurturing act of food transfer between mothers and infants. This transition from practical to intimate behavior could have had significant implications for social bonding and reproductive strategies.
Although kissing is not universally practiced among modern human cultures—estimated at around 50%—the study suggests that its variability may have existed among ancient populations. If Neanderthals engaged in kissing, it likely varied by community, much like it does today among different cultures.
Ultimately, kissing’s persistence across species raises intriguing questions. The researchers propose that kissing may enhance reproductive success by allowing individuals to evaluate potential partners through subtle chemical cues that reveal health and genetic compatibility. Additionally, kissing could strengthen social bonds and even benefit immunity through the exchange of beneficial microbes.
This compelling study opens new avenues for understanding the evolution of social behaviors in our ancestors and their relevance to modern human interactions. As the research community delves deeper into the evolutionary significance of kissing, the implications for our understanding of human connections become ever more profound.
Stay tuned for more updates as this story develops and researchers continue to explore the fascinating history of human behavior.
