🔗 Share this article Ancient Hominins and Modern Humans May Have Kissing, Scientists Suggest From seabirds to Arctic mammals, chimpanzees to great apes, various animals appear to kiss. Currently, scientists suggest that ancient hominins did it too – and might even have locked lips with modern humans. Common Oral Clues This isn't the initial instance experts have suggested Neanderthals and early modern humans were intimately acquainted. Among earlier research, scientists have found modern people and their Neanderthal relatives possessed the identical oral bacteria for millions of years after the two species split, implying they exchanged oral fluids. "Likely they were engaging in intimate contact," the researcher noted, adding that the idea chimed with studies that has revealed people of certain genetic backgrounds have bits of Neanderthal DNA in their genetic makeup, demonstrating interbreeding was at play. Romantic Spin "It certainly puts a different perspective on human-Neanderthal relations," Brindle commented. Publishing in the journal Evolution and Human Behavior, Brindle and her team detail how, to explore the evolutionary origins of kissing, they first had to come up with a definition that was not limited to how humans smooch. Describing Intimate Contact "Previously there were some previous attempts to describe a intimate act, but it's largely human-centric, which means that essentially non-human species do not engage in this. Now we understand that they probably do, it might just not look from what human kissing looks like," said Brindle. Nonetheless, she said some actions that resembled kissing were distinct activities – such as the chewing and transfer of food, or "mouth contact", observed in aquatic species known as French grunts. Consequently the research group developed a description of kissing based on friendly interactions involving intentional mouth-to-mouth contact with a individual of the same species, with some movement of the mouth but no transfer of nutrition. Research Methods The lead researcher explained they concentrated on accounts of intimate behavior in non-human species from the African continent and Asia, including bonobos, apes and orangutans, and employed digital recordings to confirm the observations. Scientists then integrated this information with details on the genetic connections between living and extinct types of such animals. Evolutionary Origins The team propose the findings suggest intimate contact evolved somewhere between 21.5 million and 16.9 million years ago in the predecessors of the great primates. The position of ancient hominins on this evolutionary lineage means it is likely they, too, engaged in a intimate act, the researchers conclude. But the activity might not have been limited to their specific group. "Reality that humans engage intimately, the reality that we currently have shown that ancient relatives probably kissed, indicates that the both groups are probably did engage," Brindle noted. Biological Significance While the scientific reasoning is debated, the expert said intimate contact could be employed in sexual contexts to potentially enhance mating outcomes or help choose between partners, while it might help reinforce bonding when used in a platonic way. Another expert in the activities of great apes commented that as kissing behavior was seen in a broad spectrum of apes it was logical its roots extend far into our ancient history, and an analysis of various types of kissing among a broader range of animals might push its origins back further still. "Behaviors that we consider as signatures of our species, like kissing, are not unique to us if we examine carefully at different species," the expert noted. Social Aspects Another professor explained that kissing had a cultural element as it was not universal to all human groups. "Nonetheless, as humans we succeed or struggle on the strength of our relationships, and ways of encouraging confidence and intimacy will have been significant for eons," the professor stated. "It might be an concept that seems a bit incongruous to our misplaced ideas of a rather ruthless and ancient history, but actually it ought to be expected that ancient hominins – and even them and our human ancestors collectively – engaged intimately."