The erotic kiss is a custom that exists in nearly every culture on Earth. Surprisingly enough, the biological role of the erotic kiss is still open for debate. One of the dominant theories is that the erotic kiss became a primary tool for gathering information about potential sexual partners. The kiss brings us in such close proximity to a new prospect that we can smell and taste them — the human face is rich with glands secreting chemicals that carry genetic and immunological information. Information such as breath quality, condition of their teeth, the exchange of vital hormonal messages, hygiene, and even energy-based information are all exchanged during a passionate kiss. The kiss also establishes one of the most vital and evolutionarily significant conditions for engaging in sexual contact — trust. Without trust, the human species would still be crawling around the plains of the African Savanna, and in this regard kissing played an essential role in how the careful selection of a sex partner helped propel us to our current evolutionary status. Another component of erotic kissing is its important role in boosting sexual arousal (testosterone is present in male saliva which may explain why the majority of men prefer wet kisses — the mouth-based transference of testosterone may significantly increase a man’s success rate for achieving sexual contact with a woman). We kiss for different reasons depending on gender and relationship type, but for all of us, kissing is both ambassador and spy. There are many more fascinating details to explore and you can read them in full by visiting PsychologyToday.com.