Boobs. They're pretty great. But we're not entirely sure why they're there in the first place.
Like all other female mammals, human women breastfeed their young but, unlike other mammals, human breasts stay full and round even when they aren't lactating.
There have been a few theories surrounding this (and an unsurprisingly large number of scientists queuing up to study boobs) but no one can quite seem to agree. Suppose they'll just have to keep looking, what a shame.
One of the main hypotheses is that they are there to attract males by signalling that the woman is healthy and fertile. This seems to make a lot of sense seeing as men love boobs so much, but it does have a couple of problems. Chief of these is that, actually, not all men love boobs. There are many cultures in which breasts are not considered to be sexual objects at all and are simply thought to be purely functional in feeding young.
The second problem we have with this theory is that it is the general rule in the animal kingdom that the males will have the flamboyant mating display to demonstrate their virility, and the plainer females will do the selecting. Because men are not essentially rendered infertile for 9 months after mating, it isn't as important to them to exclusively mate with strong, genetically desirable partners.
Another theory is that the fat content in the breasts help to fortify the milk they produce. Big-brained human babies require a lot of energy to develop their bonce, and it is thought by some that this is what the boobs are all about.
This, however, has yet to be scientifically proven. We'll just have to appreciate breasts for the mystery that they are for now.
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