Compelling evidence has emerged suggesting that the practice of kissing may have originated as far back as 21 million years ago, with indications that our ancient ape relatives and Neanderthals engaged in this form of intimate contact, according to research unveiled on Wednesday.
For a considerable period, kissing has posed an evolutionary enigma to researchers, appearing to carry substantial risks, such as the potential for pathogen transmission, without any immediately discernible advantages for reproduction or survival.
However, the most recent investigation proposes that this behaviour has undergone millions of years of evolution, postulating that our extinct human kin, the Neanderthals, might have exchanged pecks as a method of conserving warmth during the Ice Age.
This groundbreaking research, spearheaded by academics from the University of Oxford, has been disseminated within the distinguished journal Evolution and Human Behaviour.
“This marks the inaugural instance where a comprehensive evolutionary perspective has been applied to scrutinize the phenomenon of kissing,” remarked co-author Matilda Brindle, an evolutionary biologist affiliated with the University of Oxford.
“Our discoveries contribute to an expanding corpus of work that elucidates the extraordinary variety of reproductive behaviours observed among our primate relatives.”
For the objectives of this inquiry, the investigators defined kissing as “any non-hostile oral-to-oral contact devoid of food transference.”
“The findings indicate that kissing represents an ancestral characteristic within the great apes,” evolving within primate lineages between 17 and 21 million years ago, as stated by an Oxford University communiqué.
“Kissing was preserved throughout the evolutionary trajectory and remains prevalent in the majority of extant great ape species,” the statement further elaborated.
The research team commenced by gathering observational data pertaining to contemporary primates known to engage in kissing, encompassing species such as chimpanzees, bonobos, and orangutans.
Subsequently, by conceptualizing kissing as a “trait,” they meticulously mapped its occurrence onto the primate phylogenetic tree. Through the simulation of various evolutionary pathways, they were able to ascertain the likelihood that ancestral species also participated in this behaviour.
Prior investigations had already established that humans and Neanderthals exchanged oral microbes via salivary contact, furnishing preliminary evidence that these species had indeed engaged in kissing.
