a reply to: viibird
To clear up a few misconceptions:
Melanin, not Melatonin, in the skin IS indeed in DNA. DNA is a genetic blue print of an organism. Every fiber of its being is in the genetics.
Saying that it's in the skin and not in the genetics, is like saying a steering wheel is in the car, but not in the manufacturer's blueprint.
Also you don't need to have controlled conditions to have genetic changes. Scientists have mapped entire genomes of both homo sapiens and
neanderthal, as well as many great apes. Every offspring of every species studied is born with dozens to hundreds genetic mutations. In homo
sapiens the average is 60 mutations. This is absolute undisputed fact.
The difference between humans and ecoli is that ecoli only lives a few hours to a day in the right conditions. Humans live 60-80 years on average
depending on where you live. What that means is that in just one year of experiments, they go through hundreds to thousands of generations. With
humans, they reproduce every 20 years give or take. To study humans on an equivalent level they would need to be observed for 20,000 years to equal 1
year of lab study on ecoli. This is why you don't see humans evolving. It is impossible to study on that level, as genetic science is only 50 years
old or so.
If 2 populations of human were isolated into 2 completely different environments, for 20-40 thousand years they could very well become different
species. It's already began to happen, as seen with the various races of human. This is direct evidence of evolution. Sub Saharan Africa tribes are
much different when compared with most other humans because they did not breed with Neanderthals upon leaving Africa, because they didn't leave
Africa. They are the closest thing to a different species, although they'd still have quite a way to go. They are indeed homo sapiens, however. If
you kept them isolated another 50,000 years, they'd probably lose the ability to breed with other homo sapiens, hence making them (or the rest of
humans) a new species.
E coli isn't the only experiment that confirms this genetic shift over generations, either. There is also Diane Dodd's fruit fly experiment that
shows exactly how speciation via reproductive isolation can occur. Don't forget that speciation isn't long term evolution, it is the emergence of new
species. If you're looking for big evolutionary changes, you need to look at speciation events, and then multiply that by 100,000. Speciation
changes are usually small, but there's no reason whatsoever to think that small changes cannot add up over time. After thousands or millions of
speciation events in a lineage, the resulting organism would indeed be much different from the original organism.
edit on 14-8-2014 by Barcs because: (no reason given)