Love is an emotion which, like the others, has evolved to fulfil a purpose. Of course it isn't necessary to understand or even consider  the mechanics of such a thing while experiencing it. 
When an emotion is so closely bound up with one's family / spouse / children, it isn't hard to see how valuable a thing it is in a species where it can takes so many years before the offspring can fend for themselves in the world.
					When an emotion is so closely bound up with one's family / spouse / children, it isn't hard to see how valuable a thing it is in a species where it can takes so many years before the offspring can fend for themselves in the world.

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