Talk:Genetic drift

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It's not necessarily "more homozygous" (although that can be a result) - but it is defintely a matter of losing some of the (usually) isolated populations original genes. But while this is happening, other mutations (or insertions, copy errors, etc.) can occur to create a different heterozygosity. humanUser talk:Human 14:11, 16 February 2008 (EST)

Agreed. Genetic drift removes diversity, and mutation ostensibly introduces it. Ungtss 14:15, 16 February 2008 (EST)
I don't think the above statement is correct.--PalMD --You don't know harsh! 14:32, 16 February 2008 (EST)
Isolation reduces diversity; mutation (etc.) increases it. The two combined are what produce genetic drift. humanUser talk:Human 14:46, 16 February 2008 (EST)
Increase and decrease in diversity are rather difficult terms, and not always that useful. For example, the Burgess Shale has shown us that we have a much reduced diversity of phyla on our current Anthropocene. However, while "high level" diversity is reduced, speciation can still create great diversity at a lower level, cladistically.--PalMD --You don't know harsh! 15:08, 16 February 2008 (EST)
I don't think isolation reduces genetic diversity. In an isolated population, you start with a given degree of diversity. Genetic drift is the statistical tendency for the minority traits to fade out into oblivion within that isolated population. The smaller the population, the greater the effect. But the effect is not itself due to isolation. Ungtss 15:20, 16 February 2008 (EST)

mutations as genetic drift[edit]

I don't think that's quite accurate. Mutation isn't a contributor to genetic drift. Genetic drift tends to eliminate mutations from the gene pool. Check out the wikipedia article ... Ungtss 15:27, 16 February 2008 (EST)

Check out this graph from wikipedia which I think makes the effect very clear. [1] Ungtss 15:31, 16 February 2008 (EST)

Considering you left out the "small population part and didn't bother to describe the "probability" part, the article needed desperate help. It should say that in small population the probability (of losing genes) overwhelms the mutations (gaining genes), causing them to tend toward homozygosity. You also managed to leave out "This trend plays a role in the founder effect, a proposed mechanism of speciation." I suspect you only wrote the article so you could support the Cdesign Proponentsism assertion that genes only disappear, with more homozygosity appearing all over the taxa, resulting in more "species" from the lesser number of founding "baramins". humanUser talk:Human 16:13, 16 February 2008 (EST)
I wrote a stub, and everything I put in it was accurate, if not comprehensive. A wise human once told me to edit instead of whining ... Ungtss 16:33, 16 February 2008 (EST)