So that's cloning on the microscopic scale, but what about on the whole person scale ? Well, nature has been doing that too. Indeed, Humans have been harmlessly cloning themselves for generations, the commonest example being identical twins. Their DNA is identical and hence they are clones of each other. But anyone who has met a pair of twins knows only too well that whilst they look identical (except for their fingerprints which are different !) they often have very different temperaments and preferences. This is an important point because many people assume that if they clone their dead dog or cat they will get a new pet with the same loveable personality traits as the animal they owned previously. You wouldn't assume that a new born baby would know how to talk because its mother and father could, and similarly you wouldn't expect a newborn dog to obey commands - they both need training - so why assume that if you clone your dead dog you'll get anything other that a totally new pet that merely looks like your old one ? With that argument in mind, why bother cloning the dog at all ? Why not just get a new one, it would be much cheaper ! The key point is that humans' brains, and those of other animals, are shaped throughout life by experience and so if two clones have different experiences in life, they will be two totally different individuals.
So are humans alone in cloning themselves naturally ? Certainly not - as a matter of course nine-banded Armadillos produce quads, where the embryo splits four ways, forming four clones, whilst female greenfly clone themselves to quickly increase their numbers when they find a good source of food. For them the reason is probably safety in numbers. If there are lots of them and some get eaten by predators, the chances of an individual greenfly getting picked on are much smaller if it is one of many. At the smaller end of the spectrum, bacteria clone themselves by copying their DNA and then splitting in half, and there are many species of plants and even fungi that reproduce merely by copying themselves. So what's the fuss about cloning considering that it's been going on under our noses, and even in our noses, for donkeys years ?
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