The evolution of kissing: New study pushes the “first kiss” back 17 million years

Do you consider kissing a feeling of romance or a survival instinct? What if it is a ritual deeply embedded in our biology, originating from the common ancestors of humans and primates? A new study that has shaken the scientific world takes the origins of kissing back 17 million years, revealing not only the secrets of relationships, but also the deeper mechanisms of human evolution. Read the analytical report on newssky.com.ua — you have a chance to witness a “revision” of the very concept of intimacy.

When was the “first kiss”: fossilized facts and biological evolution¹

New interdisciplinary study published in leading journal Science Advances, argues that kissing is not just a cultural practice of Homo sapiens or Neanderthals. It originated at least 16,9 million years ago, coinciding with the emergence of the last common ancestor of humans and chimpanzees. Using ethology, paleontology, and genetics, the authors traced the relationship between the behavior of modern primates, humans, archaeological burials, and traces of pathogens transmitted through oral contact.

Is kissing a primate legacy or a universal human phenomenon?

Over 80% of modern ape species exhibit various forms of “kisses” as part of social rituals: mothers use them to soothe their young, males and females use them to strengthen pair bonds, and groups use them to restore harmony after conflicts.
Unique archaeological finds from caves in Spain and France (Neanderthals) show that burials of couples often contained traces of pathogens that are transmitted only through contact of lips or saliva.
Ancient Indian, East Asian, and African writings describe “kisses” as a ritual of peace, greeting, or initiation.

Why kissing doesn't exist in all cultures¹

Interestingly, according to a representative study from 2015, less than half of the world's people practice romantic kissing - in many cultures, this habit is not only absent, but also considered strange or even forbidden.
At the same time, all cultures know kissing as a sign of care: a mother kissing her child, or a “friendly” kiss within a tribe.
Conclusion: the evolutionary essence is the transfer of security, nutrition, immune agents, and the creation of social bonds.

What role did kissing play in the evolution of humans and other hominids?¹

Kissing could have powerful adaptive significance: helping to form children's immune memory through the exchange of microbiota, strengthening pair bonds, and regulating attachment hormones (oxytocin, dopamine).
Ancient people transmitted information about their health, stress levels, and emotional balance to each other through the touch of their lips.
Later social customs (consecration, peace agreements through the “kiss of peace,” initiation into warriors) are only a “superstructure” on top of the biological mechanism.

What anthropologists and biologists say about the modern kiss

– A kiss is a distant “relative” of mouth-to-mouth feeding in animals, and not just a romantic one.
– It “works” at the immune level: in kissing couples, up to 80% of the bacterial composition of the oral cavity is synchronized.
– For many modern couples, a kiss is more important than sex as a “litmus test” of emotional harmony (data from sociological research by the University of Virginia, published in 2023).

Did Neanderthals kiss: evidence and mysteries

The scientific team notes that traces of specific amino acids and bacteria of the genus were found alongside the remains of Neanderthal families. neisseria, which are transmitted only orally. This suggests that Neanderthals practiced contact similar to kissing.
In addition, rock paintings in Africa and South America depict ritual touches of lips to foreheads or hands — the probable “ancestors” of modern kisses.

Evolution today: why kissing remains important

– Neurophysiologists claim that kissing is a powerful anti-stress that reduces cortisol levels and blood pressure.
– Modern psychology defines a kiss as a “trigger” of emotional unity and trust.
– Even in the world of “distance,” a kiss remains a universal symbol not only of love, but also of humanity, compassion, and friendship.

Conclusion: kissing is our ancient ritual and the secret of survival

Revolutionary research has proven that kissing is not just a tradition or a "lover's invention," but a fundamental mechanism that ensured survival and emotional development even when humans were not humans. Its significance is not only in culture, but also in the molecular memory of evolutionary experience that makes us true Homo sapiens.

Sources

1. washingtonpost.com. Kissing evolved over 17 million years ago, study suggests
2. science.org. Kissing – an ancient practice in mammals?
3. anthrosource.onlinelibrary.wiley.com. Are romantic-sexual kisses a human universal?
4. virginia.edu. Study: The emotional impact of kisses in relationships