Saem said:
Thank you, thank you. I was thinking the same thoughts when reading Saem and KILER's responces. People never look at the whole picture as you stated, instead they just focus on this small window of mutations, Mary Shelley inspired monsters and other undesireable aspects. It pains me to hear it.
This seems like a flawed point of view. It doesn't happen in nature, in nature genetic diversity is preserved. While if we had genetic manipulation, there would be significantly less genetic diversity.
That's another myth about nature. An almost religious one, that nature is in harmony, and self balancing, yadda yadda. Reductions of diversity occur all the time, even without man's influence.
But if you want to look at particular examples in human beings, just look at blond hair/blue/green eyed Europeans. There are only two plausible ways we can account for the existence of blue/green eyes for example:
Either 1) white tribes long ago with blue/green eyes, blond/brown hair, etc decided to not interbreed with any outsiders (or they simply killed them) or 2) some spontaneous mutation continues to keep the genes involved coming back
Why? Because if you crunch the numbers, any population of people with blue/green eyes will have bred the genes responsible out in just a few generations in the presence of only a few people with brown eyes. How to explain the unnatural persistence of these genes which disappear quite quickly in the presence of dominant brown genes. Therefore, white people have been practicing selective breeding with respect to blue/green eyes, and light colored skin and hair.
Another example is the Han in China. Just a few millenia ago, people in China were racially diverse. Now the vast majority of people have brown eyes, black hair, and Han facial structure. Again, how to explain it except through selective breeding or ethnic cleansing?
If people did not attempt to select the genes they wanted to pass onto their children, we would expect them to select mates in a way that would preserve diversity, instead, diversity dropped. Even if you factor in cultural attitudes towards marrying outside your tribe, those attitudes themselves are based on evolutionary biological reasons. (I am in no way saying they are "correct" behaviors in modern society, but there are reasons people have evolved these behaviors)