Friday, November 2, 2012

Once More With Feeling

Hear me out; I may be onto something.

Maybe it’s all a matter of semantics, of word choice.

The problem is in the phrase “natural selection”; it implies choice. In people’s minds it implies that the selecting being done is being done by the individual members of the species, and that it’s that selecting which affects the direction of evolution; i.e. successful females get together with successful males (of whatever species), and they breed successful offspring which informs the direction of their evolution.

No. There are two way to make selections: one is by choice; and the other is by attrition. Natural selection is of the second variety: those who are left standing at the end are those who are chosen. We think of natural selection as of the first kind, but in truth, it’s of the second.

Natural selection happens at the species, not the individual, level. Natural selection doesn’t care how successful any individual is; it only cares whether or not the individual’s genes give rise to successful generations. It only cares what the individual contributes to the gene pool, not its individual success. All those pecking orders and strict animal hierarchies have nothing to do with mating the best specimens; they’re simply ways of A) insuring the shuffling of genes, and B) maintaining social order within the species.

It is not in a species’ interest to keep only its best specimens alive; it’s best interests are to keep as many of its members alive as possible.

Ergo, the only natural selection being done is a matter of success: either a mutation has it or it doesn’t. And really, that’s no selection at all; it’s dumb luck.

Think of it this way. Igor the cowherd was on the bottom rung of the ladder. He wasn’t the brightest of candles, was prone to disease, and spent a lot of his life alone with his cows in the mountains. This was a very, very long time ago. Before they’d brought those cows to Europe; they were still hanging around the Caucasus. Igor also had a penchant for barley beer and didn’t look much to the future.

Igor hooked up with Priscilla who was, perhaps, a little slow on the uptake and had trouble walking in a straight line, but she was happy enough with the lone cowherd. Their life would not be remarkable; they brought three children into the world before Igor was kicked in the head by a cow and killed. Alas. The only thing unusual was a small mutation in Igor’s constitution. Everyone at the time was lactose intolerant. That’s the usual human condition; it takes living with cows and drinking their milk for millennia before chance provides a lactose-tolerance mutation. Wouldn’t you know it, that mutation happened to Igor.

It didn’t, of course, help Igor—he was kicked to death at a young age—but two of his three children inherited the gene. It didn’t make a big difference in their life, either, though they did tolerate dairy products better than their kin. It wasn’t a huge change, but, considering their livelihood, it would eventually have a big impact on their culture. Those children who inherited the new gene did a little better than their neighbors. It was a useful gene and it slowly got passed around to most everyone in the tribe. Those who had it had a better survival rate than those who didn’t.

The king’s family? They never got the gene and were wiped out some years later in a coup. Alas.

And that’s how natural selection works. No one ever selected Igor’s family to be the hope of the future, other than chance. No one even noticed that it was Igor’s descendants who changed their people forever. Who would have imagined? No one, and no one did.

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