Our breathing can deepen and become irregular. Our heart starts to race, our pupils dilate which might be one of the reasons so many people close their eyes during a kiss.
There are three sensations that one should really recognise when they're kissing. First of all, there's the wonderful feeling of touch because our lips are extremely sensitive, we have more nerve neurons on the end of our lips than any other place in our body, except some areas in our genitalia.
And then of course also there's taste. Each individual has a unique taste to them and some people are much better at recognising taste than others and then of course there's also smell.
Ovid in some of his poems talked about kisses smelling like ripening apples in a chest. There's a lot of theories as to why we kiss but some of it may have to do with our earliest experiences on planet Earth.
When we're infants, through being kissed by parents and also through nursing, through a lot of lip stimulation that becomes associated through neural pathways in our brain with these very, very positive emotions. And so we're building these neural pathways that attribute kissing and lip stimulation with love and security and all of these wonderful things that later in life when we want to express ourselves that way, we probably do so using our mouth.
While we can't zip ourselves back in time and kind of discover when and where and how the first kiss took place among humans, what we do know is that other species are very attracted to the rosy bottoms of females when they're at peak fertility when they're in estrus. There are some anthropologists that think that the lips are what's called 'the genital echo' so they mimic the female genitals in shape, composition, colour, and texture, and they serve as a reliable indicator of when a woman might be ready to mate.
Desmond Morris, a British zoologist, he's actually done some research on lipstick, showing different men images of women's faces asking who the most attractive are? And over and over and over men are consistently choosing the women who are expressing the rosiest most coloured lips in these studies.
So there's something that does draw our attention to the mouth and the colour red is a colour that many species use to exhibit this sexual signal. The earliest evidence that we find of any kind of kissing is about 2,500 maybe 3,500 years ago, in some of the early Vedic texts that come from India.
It turns out that the area right below your eyes has sebaceous glands that produce a unique smell for each individual. So these ancient Indians in northern India were sniffing each other and of course, they ran their noses across the cheeks of each other and then across the nose to the other side of the cheek.
I think that occasionally some of them slipped and may have ended up on the lips and because the lips are so sensitive, they may have found that that was much more pleasurable than just sniffing each other. The Romans can be looked upon really as probably the first great kissing culture.
