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Comment by deeviant | Hacker News Reader

I don't get this statement, and it goes against my understanding of evolutionary forces.

Of the 5 evolutionary forces that I am aware of, founder effects, genetic drift, mutation, migration and selection, only one "responds" to the environment (selection). To respond to an event such as the invention of eating utensils, selection would dictate that a particular trait would have to give a survival/mating advantage over not having it.

It is suggested that those with an overbite we able to survive/mate better in the presence utensils than those without an overbite?

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I know nothing about biology, but how about this:

The evolutionary path was influenced via selection. Those who made and used tools were more likely to survive/mate successfully, and those who made and used tools also tended to use them as eating utensils, which mechanically leads to an overbite. So eating with a fork doesn't directly lead to being selected for survival, but it's likely if you eat with utensils you also use other tools for things like hunting, defence, etc. and that does lead to increased survival.

It doesn't work like that.

That type of association is called "Lamarckian" after Jean-Baptiste Lamarck who posited that animals can "pass on characteristics that it acquired during its lifetime to its offspring"[1]. But animals do not pass on traits they acquired during their lifetime via genetics.

So even if utensils over one's life caused a overbite, it would not be transmitted via genetics to one's offspring. In order for evolution and utensils to interact via selection, it would have to be the case in which there was a genetic trait associated with an overbite that made you more fit when using utensils than those without it, thus out-mating the competition.

[1]http://en.wikipedia.org/wiki/Lamarckism

Why can't the opposite be true; those without an overbite are able to survive/mate better in the absence of utensils? Then the modern presence of overbite is easily explained as genetic drift.

I would guess that many modern mutations could be explained this way -- human invention alleviates evolutionary pressure keeping historically negative traits from flourishing.

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