🔗 Share this article Neanderthals and Early Humans Were Likely Engaging in Intimate Contact, Researchers Suggest From Galápagos albatrosses to Arctic mammals, chimpanzees to orangutans, various animals appear to kiss. Now, scientists propose that ancient hominins also engaged in this behavior – and possibly locked lips with early Homo sapiens. Shared Oral Evidence It is not the first time scientists have proposed ancient relatives and early modern humans were closely connected. In previous studies, researchers have discovered modern people and their thick-browed cousins possessed the identical oral bacteria for millions of years after the evolutionary divergence, implying they swapped saliva. "Likely they were engaging in intimate contact," she said, explaining that the idea chimed with research that has found people of certain genetic backgrounds contain ancient genetic material in their genetic makeup, revealing genetic mixing was occurring. Romantic Interpretation "It certainly puts a more romantic spin on human-Neanderthal relations," the lead researcher said. Writing in the publication a scientific periodical, Brindle and her team detail how, to investigate the evolutionary origins of intimate contact, they first had to develop a description that was not restricted by how humans smooch. Describing Kissing "Previously there were some previous attempts to define a intimate act, but it's very much been focused on humans, which implies that essentially non-human species do not engage in this. Now we understand that they likely engage, it might just not look from what our intimate contact looks like," said Brindle. Nonetheless, she noted some actions that looked like intimate contact were distinct activities – such as the processing and transfer of food, or "kiss-fighting", seen in fish called certain marine animals. Consequently the research group developed a definition of intimate contact centered around friendly interactions involving directed oral interaction with a member of the identical group, with some motion of the mouth but no transfer of nutrition. Study Methods The lead researcher said they focused on accounts of kissing in non-human species from Africa and Asia, including primates, apes and great apes, and employed online videos to verify the reports. Scientists then integrated this data with information on the evolutionary relationships between extant and ancient types of such primates. Historical Timeline Researchers say the findings suggest kissing evolved approximately 21.5m and 16.9m years ago in the predecessors of the great primates. The position of ancient hominins on this family tree means it is likely they, too, engaged in a intimate act, the scientists say. But the behavior may not have been limited to their own species. "Reality that modern people engage intimately, the fact that we now have demonstrated that ancient relatives very likely engaged, suggests that the two [species] are probably did kissed," the researcher noted. Evolutionary Significance Although the scientific reasoning is debated, Brindle explained kissing could be employed in reproductive situations to possibly increase reproductive success or assist in selecting between partners, while it could assist strengthen connections when practiced in a platonic way. Another expert in the behavior of primates commented that as kissing behavior was observed in a broad spectrum of primates it made sense its origins lie deep in our evolutionary past, and an analysis of different forms of intimate behavior among a wider variety of animals might extend its origins back further still. "Things that we consider as signatures of our species, like intimate contact, are not unique to us if we look closely at other animals," the expert noted. Cultural Elements Another professor explained that intimate contact had a cultural element as it was not common to all societies. "However, as humans we thrive or fail on the strength of our relationships, and methods of encouraging trust and intimacy will have been important for millions of years," the professor stated. "It might be an concept that seems a bit contradictory to our misplaced ideas of a rather ruthless and ancient history, but really it ought to be no surprise that ancient hominins – and even them and our own species collectively – kissed."