🔗 Share this article Ancient Hominins and Modern Humans Were Likely Kissing, Researchers Suggest Among Galápagos albatrosses to Arctic mammals, chimpanzees to orangutans, various animals appear to kiss. Now, researchers propose that ancient hominins did it too – and possibly exchanged kisses with early Homo sapiens. Shared Oral Clues It is not the first time experts have suggested ancient relatives and Homo sapiens were closely connected. Among earlier research, scientists have discovered humans and their thick-browed cousins shared the identical oral bacteria for millions of years after the two species split, implying they exchanged oral fluids. "Likely they were kissing," the researcher noted, adding that the idea aligned with research that has found humans of non-African ancestry have bits of ancient genetic material in their genome, demonstrating interbreeding was at play. Intimate Interpretation "It certainly puts a different spin on human-Neanderthal relations," Brindle commented. Publishing in the journal a scientific periodical, the researcher and her team detail how, to explore the historical roots of intimate contact, they first had to come up with a description that was not restricted by how humans smooch. Describing Intimate Contact "Previously there were some previous attempts to describe a kiss, but it's largely human-centric, which implies that basically non-human species don't kiss. Currently we know that they likely engage, it may appear different from what human kissing looks like," explained Brindle. However, she said some behaviors that looked like intimate contact were distinct activities – such as the chewing and food sharing, or "kiss-fighting", seen in fish known as certain marine animals. Consequently the team developed a description of kissing based on friendly interactions involving directed oral interaction with a individual of the identical group, with some motion of the oral area but no transfer of nutrition. Research Approach Brindle said they focused on reports of kissing in primates from Africa and Asian regions, including primates, chimpanzees and orangutans, and used online videos to verify the observations. Scientists then integrated this information with information on the evolutionary relationships between extant and ancient types of such animals. Evolutionary Origins Researchers propose the results indicate kissing evolved approximately 21.5m and 16.9 million years ago in the ancestors of the great primates. The position of Neanderthals on this evolutionary lineage means it is probable they, too, engaged in a kiss, the researchers conclude. But the activity may not have been confined to their specific group. "The fact that modern people kiss, the reality that we now have demonstrated that Neanderthals very likely kissed, suggests that the both groups are probably did kissed," Brindle added. Evolutionary Importance While the scientific reasoning is discussed, Brindle said intimate contact could be used in sexual contexts to potentially increase mating outcomes or assist in selecting between partners, while it might help strengthen connections when used in a platonic way. Another expert in the activities of primates said that as kissing behavior was seen in a wide range of primates it was logical its origins extend far into our evolutionary past, and an examination of different forms of kissing among a broader range of species might extend its origins back even earlier still. "Behaviors that we consider as characteristics of our species, like kissing, are not unique to us if we examine carefully at other animals," the expert noted. Cultural Aspects An archaeology expert explained that intimate contact had a social component as it was not universal to all human groups. "However, as humans we thrive or fail on the strength of our emotional bonds, and methods of promoting confidence and intimacy will have been significant for eons," she said. "This could represent an image that appears a bit incongruous to our misplaced ideas of a rather ruthless and ancient history, but really it should be no surprise that Neanderthals – and including them and our own species together – engaged intimately."