🔗 Share this article Neanderthals and Early Humans Were Likely Kissing, Scientists Suggest Among Galápagos albatrosses to polar bears, primates to great apes, certain species appear to kiss. Now, researchers propose that Neanderthals did it too – and might even have exchanged kisses with early Homo sapiens. Common Microbial Evidence This isn't the initial instance scientists have proposed ancient relatives and Homo sapiens were closely connected. Among earlier research, researchers have discovered humans and their thick-browed cousins shared the identical oral bacteria for millions of years after the two species split, suggesting they swapped saliva. "Probably they were kissing," the researcher noted, explaining that the concept chimed with studies that has revealed people of certain genetic backgrounds contain Neanderthal DNA in their genetic makeup, revealing interbreeding was at play. Intimate Spin "It certainly puts a different spin on human-Neanderthal relations," Brindle commented. Publishing in the journal a scientific periodical, the researcher and colleagues detail how, to explore the historical roots of intimate contact, they first had to develop a description that was not restricted by how people kiss. Defining Kissing "There have been some efforts to define a kiss, but it's very much been human-centric, which implies that basically other animals don't kiss. Currently we understand that they probably do, it might just not look from what human kissing looks like," explained Brindle. However, she noted some behaviors that resembled intimate contact were distinct activities – such as the processing and food sharing, or "kiss-fighting", observed in aquatic species called French grunts. Consequently the research group came up with a definition of kissing based on friendly interactions involving intentional mouth-to-mouth contact with a individual of the identical group, with some motion of the mouth but absence of food. Research Approach The lead researcher said they focused on accounts of intimate behavior in non-human species from Africa and Asia, including bonobos, chimpanzees and great apes, and employed online videos to verify the observations. Scientists then combined this information with details on the evolutionary relationships between extant and extinct types of such animals. Evolutionary Origins The team propose the findings indicate intimate contact evolved somewhere between 21.5m and 16.9 million years ago in the predecessors of the great primates. Placement of Neanderthals on this family tree means it is likely they, too, indulged in a kiss, the scientists conclude. But the activity might not have been limited to their specific group. "The fact that humans engage intimately, the reality that we now have demonstrated that Neanderthals probably engaged, suggests that the both groups are probably did kissed," the researcher noted. Biological Importance While the scientific reasoning is debated, the expert explained intimate contact could be used in sexual contexts to potentially increase reproductive success or help choose between partners, while it could assist reinforce bonding when used in a non-sexual manner. Another expert in the behavior of primates said that as intimate contact was observed in a broad spectrum of apes it made sense its roots lie deep in our ancient history, and an examination of various types of kissing among a broader range of animals might push its origins back even earlier still. "Things that we think of as signatures of human life, like kissing, are not exclusive to us if we examine carefully at other animals," the expert noted. Social Elements Another professor explained that kissing had a social component as it was not universal to all human groups. "Nonetheless, as humans we thrive or fail on the strength of our relationships, and ways of encouraging trust and intimacy will have been important for millions of years," the professor stated. "This could represent an image that seems a bit incongruous to our misplaced ideas of a rather ruthless and ancient history, but actually it ought to be no surprise that ancient hominins – and even them and our human ancestors together – engaged intimately."