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Sunday, June 21, 2009

Natural vs. unnatural selection: Consider the ceaseless yap of the lap dog and be warned

In "Actually, the goal posts were just pulled up. Too much trouble to move...", I linked to Jonathan Well's comment on subtle attempts to change just what Darwinian evolution means, to avoid disconfirmation of any particular model. You know, first it's natural selection only, then, lo and behold, group selection is allowed, then Lamarckism (inheritance of acquired characteristics), then gene swapping ...

First junk DNA proved Darwin was right, then when it turned out not to be junk, you can be pretty sure, it will still prove Darwin was right. Darwinism has become a catch-all for a tired, worn-out theory, hysterically popular in the academic culture, with no real foundation for why.

Anyway, Mike Flannery, author of Alfred Russel Wallace's Theory of Intelligent Evolution, comments on my notes on the obviously unsupportable claim that artificial selection (= animal breeding) supports Darwinian evolution (random mutation acting on natural selection):
Anyone can breed a weird dog (I mean, assuming they have basic knowledge of canines).

But nature has a funnel.

There are only certain ways that dogs can really live in the wild.

For example, a greyhound can run faster than a wolf, because he doesn’t have heavy jaws - but what happens when he catches up with the prey?

Someone throws him a bag of Science Diet for Adult Working Dogs, right?

Human interventions almost always assume that we protect the life form from the normal routine of nature – otherwise there would be no reason to bother.

And nature is limited to certain routines. A wild animal that cannot feed itself will die.

But a Bassett Hound can live as long as its owner is willing to pay for advanced veterinary medicine, necessitated in part by the odd way the creature was bred.

If all the dogs in the world ran away, 50 years later, you would likely see only nature's usual wolfhound type.
Anyway, Flannery comments,
Jonathan revealingly quotes Mirsky in his excellent piece: "As Darwin did before him, Coyne noted that the development of new breeds through artificial selection is a good model for the evolution of new species by natural selection."

The model wasn't good when Darwin presented it and it cannot be improved in Coyne's re-telling. From the very beginning (even in the famous Ternate Letter of 1858), Alfred Russel Wallace pointed out, "in the domesticated animal all variations have an equal chance of continuance; and those which would decidedly render a wild animal unable to compete with its fellows and continue its existence are no disadvantage whatever in a state of domesticity. Our quickly fattening pigs, short-legged sheep, pouter pigeons, and poodle dogs could never have come into existence in a state of nature, because the very first step towards such inferior forms would have led to the rapid extinction of the race; still less could they now exist in competition with their wild allies. The great speed but slight endurance of the race horse, the unwieldy strength of the ploughman's team, would both be useless in a state of nature.

If turned wild on the pampas, such animals would probably soon become extinct, or under favourable circumstances might each lose those extreme qualities which would never be called into action, and in a few generations would revert to a common type, which must be that in which the various powers and faculties are so proportioned to each other as to be best adapted to procure food and secure safety,--that in which by the full exercise of every part of his organization the animal can alone continue to live. Domestic varieties, when turned wild, must return to something near the type of the original wild stock, or become altogether extinct." Wallace never would agree with Darwin on this point and it would lead to other more significant disagreements later.

Besides, AT BEST all domestic breeding examples merely established one thing: GUIDED and DIRECTED variation.
Maybe I am a Wallacist?

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