Random Mutation as Driver of Evolution

I think we need to start calling this kind of snipping for political effect Sherrodism or Sherroding your opponent.

Artificial selection (or selective breeding) describes intentional breeding for certain traits, or combination of traits. The term was utilized by Charles Darwin in contrast to natural selection, in which the differential reproduction of organisms with certain traits is attributed to improved survival or reproductive ability (“Darwinian fitness”). As opposed to artificial selection, in which humans favor specific traits, in natural selection the environment acts as a sieve through which only certain variations can pass.

A. S. is behind eugenics. I can see employing several genetic interventions to reduce , say Tay-Sacks or Sickle Cell. I just dont see us being an agent of manipulation of Nat selection.

We have been perfectly capable of manipulating natural selection without genetics. It's called "farming" and "stock-breeding", and it's been going on since Neolithic times.

bonacquist wrote:

Random mutation is a very inefficient means of driving evolution, since most mutations are not adaptive. Why hasn't life over the eons hit upon a more efficient means of evolving?

Evolution is NOT driven by random mutation. Mutations happen but it is natural selection that drives evolution. An evolutionary change that helps an organism to survive in a particular ecosystem gets passed on to future generations. Successful adaptations are thus connected to the specifics of a natural environment. Natural selection is anything BUT random.

If you were right, the gene pool would evolve until everyone had the best genes and then stop. New improvements would have no mechanism of making their way into the gene pool.

There can't be BEST, brandon, because condition constantly change. The happy beasties in the Louisiana/Mississippi coastal swamps from last year maybe different in some ways next year. Maybe 99% of a particular mollusk will be killed by the oil, but the remaining 1% may have a peculiar defense against petro products.....or maybe they just didn't get hit hard enough to expire.
The population may have changes simply from the reduction of the number of parents spawning new mollusks OR there may not be any discernible changes at all.

Joe(what life was a minute ago, won't be the same as it will be in a minute and a half.)Nation

If a certain percent have a given gene and all those that don't have the gene die off due to environmental changes then the gene becomes prevalent without any changes in the existing gene structure.

adaptation doesnt necessarilly take "new genes" to start the evolutionary ball rolling. Also "new genes" can be brought into a genotype from fertilization of a single point mutation on the lines of one of the parents. While technically a mutation, it is responded to by selector genes within the cell makeup of the offspring .
What Joe was speaking about was the fact that a "hopeful monster" already gifted with that single point , may actually thrive in petroleum fouled water. No new genes were necessary really, just a shuffle of the existing ones.

The mechanism for introducing new traits into the genepool is accidental mutation. Evolution requires both selection and the introduction of new traits.