The unromantic truth about why we kiss - to spread germs

It is an international symbol of love and romance. But the kiss may have evolved for reasons that are far more practical - and less alluring.

British scientists believe it developed to spread germs.

They say that the uniquely human habit allows a bug that is dangerous in pregnancy to be passed from man to woman to give her time to build up immunity.

Read more:–spread-germs.html#ixzz0VWSPUKRz


What I’ve heard about it is that our lips are one of the most sensitive parts of our bodies, and kisses came about that way.

How would ancient people have figured out germs though?

Sounds like storytelling to me.

That’s what I was thinking. :stuck_out_tongue:

This sounds like a matter of evolution scientists reverse engineering evolution (i.e. this act has a beneficial function; therefore it must have been part of evolution). It doesn’t sound very scientific to me…

Kissing the same person for about six months provides optimum protection, he added.

During a relatively chaste first kiss, just a small amount of virus is passed to the woman, cutting her odds of becoming ill.

Don’t fancy yours much: The cytomegalovirus up close

As the relationships progresses and the kisses become more passionate, her immunity builds up.

Well, secular society is doomed I guess - multiple partners and one-night stands are not going to properly inoculate anyone…then there’s test tube babies, surrogate mothers, etc. :frowning:

They didn’t, I would wager. Those females who didn’t go in for kissing, or partnered with males who didn’t kiss them, had little immunity and therefore suffered more miscarriages or bore more infants with birth defects. Those who did engage in mouth-to-mouth immunization (lol) suffered fewer miscarriages, and therefore had more offspring who survived, who learned their parents’ habits? Enough generations of that and kissing becomes a near-universal* human practice.

*I say ‘near-universal’ because hey, there might be societies where kissing… isn’t done. I’m not aware of any, but let’s be fair! :stuck_out_tongue:

Exactly. That is what I mean by “reverse engineering.” Kissing did not come about through evolution. In fairness, it could just be the author of the article who made the mistake, but man didn’t start kissing to “spread germs.” It is the other way around. The kissing started for other reasons (pleasure, no doubt) and the benefit was a positive effect on the survival of offspring.

No one in the ancient world looked around and said “hold on…that group over there kisses a lot, and their infant mortality rate is much improved…perhaps, we should start kissing, as well.” :stuck_out_tongue:

Sounds doubtful - normal daily contact with people probably spreads germs efficiently enough without kissing being required.

What I have read, and verily believe to be the case, is that animals rely on scent more than anything else in identifying each other. So those who are in the same family group mark each other with their scent so that they can truly be recognised as ‘one of the family’. This is one reason your cat will rub up against your leg, they are marking you as an honorary member of their clan!

Kissing (be it on the cheek or, more so, on the mouth) spreads sebum - skin oils. These contain OUR scent. So when WE kiss someone WE are marking them with our scent - and can more easily recognise them as friend/family rather than stranger or foe.

All I can picture is a dog marking his territory.:doh2: I can’t really wrap my mind around this one…

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