When you share a kiss with your lover on Valentine's Day, you may be revealing a lot more than you realise. Locking lips not only stimulates our senses, it also gives us subtle clues about our suitability as mates, US scientists have found.
A man's saliva has a «cocktail of chemicals» hinting at his fertility and evolutionary fitness, they said at a conference in Chicago.
That may be why the first kiss is often the last - «the kiss of death)).