🔗 Share this article Neanderthals and Early Humans Were Likely Kissing, Scientists Propose From Galápagos albatrosses to Arctic mammals, chimpanzees to great apes, various animals appear to kiss. Now, researchers propose that Neanderthals did it too – and possibly exchanged kisses with early Homo sapiens. Shared Oral Evidence It is not the first time experts have proposed ancient relatives and Homo sapiens were closely connected. In previous studies, researchers have discovered modern people and their Neanderthal relatives possessed the same mouth microbe for hundreds of thousands of years after the two species split, implying they swapped saliva. "Likely they were kissing," the researcher noted, adding that the concept aligned with studies that has revealed humans of non-African ancestry have bits of ancient genetic material in their genetic makeup, revealing genetic mixing was at play. Romantic Interpretation "This offers a different spin on ancient interactions," Brindle commented. Publishing in the journal a scientific periodical, Brindle and colleagues detail how, to explore the historical roots of kissing, they first had to come up with a description that was not limited to how people smooch. Describing Intimate Contact "There have been some previous attempts to define a kiss, but it's very much been focused on humans, which means that basically non-human species don't kiss. Now we understand that they likely engage, it may appear different from what human kissing looks like," said the evolutionary biologist. Nonetheless, she said some actions that looked like kissing were something rather different – such as the chewing and transfer of food, or "kiss-fighting", observed in fish known as French grunts. As a result the research group developed a definition of intimate contact centered around friendly interactions involving intentional mouth-to-mouth contact with a individual of the same species, with some movement of the mouth but absence of food. Research Approach The lead researcher explained they focused on accounts of intimate behavior in primates from the African continent and Asia, including primates, apes and great apes, and employed online videos to verify the reports. The researchers then combined this data with details on the evolutionary relationships between living and extinct species of such primates. Evolutionary Origins The team propose the findings suggest kissing developed somewhere between 21.5m and 16.9 million years ago in the ancestors of the large apes. Placement of ancient hominins on this evolutionary lineage suggests it is probable they, too, indulged in a kiss, the scientists say. But the activity may not have been confined to their specific group. "The fact that modern people engage intimately, the fact that we currently have shown that Neanderthals probably kissed, suggests that the both groups are also likely to have engage," the researcher added. Biological Importance While the evolutionary explanation is discussed, Brindle explained kissing could be used in reproductive situations to possibly increase reproductive success or help choose between mates, while it might help reinforce bonding when used in a non-sexual manner. A separate researcher in the behavior of primates commented that as kissing behavior was observed in a broad spectrum of apes it made sense its roots lie deep in our ancient history, and an examination of different forms of intimate behavior among a wider variety of species might extend its origins back even earlier still. "Behaviors that we consider as characteristics of our species, like intimate contact, are not unique to us if we look closely at other animals," the expert noted. Cultural Elements An archaeology expert said that intimate contact had a cultural element as it was not universal to all societies. "Nonetheless, as people we thrive or fail on the quality of our emotional bonds, and ways of encouraging confidence and closeness will have been important for eons," the professor stated. "It might be an concept that seems a bit contradictory to our incorrect assumptions of a supposedly aggressive and ancient history, but actually it should be expected that Neanderthals – and including them and our human ancestors collectively – engaged intimately."