Lack of Human varieties. Genetic "cleansing" through history?

ok, then so what?Lets assume no interbreeding and that the Neaders were killed off by modern humans. Now what?Its just another step in the evolutionary journey.

I'm not talking about extinction from an inability to adapt to a changing environment. I'm talking about ethnic cleansing, i.e. murder of a whole "kind".
Heres the thing with that talk of 99% of all creatures being extinct. These different human varieties lived at THE SAME TIME. They saw one another. But according to DNA, there was no interbreeding. Neanderthal died on its own, and how and why, no one knows why.

But that IS what you are talking about. The Neandetals evironment changed, it became filled with modern humans, and they were unable to survive it.

Like CS said, that's exactly what you're talking about. "Environment" doesn't mean "the scenery", it refers to the area where you live and the other creatures that inhabit it. Organisms adapt to things like predation and disease - other creatures - as much as they might adapt themselves to hot or cold climes. These aren't ethnicities we're talking about, though. These aren't two different races of Homo sapiens; these are two different species that may or may not have even been interfertile. Well, I'm not sure the jury isn't still out on that. A lot of the studies have been criticised for a biased methodology where anytime human DNA is detected in Neanderthal samples, it's assumed to be sample contamination from handlers and excavaters. If that assumption is erroneous then the studies might be throwing out genuine human sequences in Neanderthal DNA by mistake. Not likely, but possible. I don't even know for sure how you would tell the difference between lab contamination and actual Homo sapiens sequences in N. DNA. They were probably out-competed for resources, if not outright killed in interspecific warfare. I agree with you that hypotheses that N. "blended in" to our gene pool are speculative at best and supported by little to no evidence.

So you're saying that Hitlers "final solution" was evolution in play? The jews were unfit for survival? They were just as fit for survival as the germans, biologically speaking. What are we talking about here? Are we all saying that evolution is NOT biological in nature all the time? The jews werent being killed off because of a biological inferiority. It was political madness. I think im talking more along the lines of social darwinism vs. biological evolution. I would like to see an example through history where an animal was driven to extinction simply through "killing for fun". Not talking about men, using weapons, who are driving animals to extinction for monetary reasons. I'm talking about say, T-Rex wiping out an entire species...not through hunting for survival, but systematically roaming the earth, wiping out an entire species because the predator feels emotionally threatened by it's prey's differences. Homo sapiens will commit genocide for reasons that defy logic. It will commit genocide when its own survival is not in jeapordy by another kind. What other animal does this? What other animal sets out to wipe out an entire species because they dont like the way it looks, or speaks, or walks or whatever. Given the fact that we have seen this happen, who is to say that homo sapiens didnt wipe out homo erectus and neanderthal because they were different, and not for control of resources? Evolution weeds out the weak. Homo Sapiens takes mother nature in its own hands and weeds out the "weak"....even though these "weak", are not weak in biological terms. If mother nature was still in control of things, these "weak" would survive. Homo Sapiens does not flow with the laws of nature like everything else. It commits acts that serve no purpose for the benefit of adaptation or evolution.
I know that neanderthal was a different species. What is all the talk about possible infertility? Saying "they may or may not have been infertile" is like saying "I'm either dead or not dead". If there is no evidence to support it, it should be left alone.

I have no idea what you're talking about, here. If you expect me to be able to draw the precise line between evolutionary determinism and personal initiative, you expect far too much from an internet forum.The fact is, Hitler's genocide had a measurable effect on the gene pool. We can examine it in evolutionary terms because it resulted in a change in allele frequencies. Does that mean than I'm sweeping the crimes of the Holocaust under a scientific rug, or trying to let Hitler off the hook? Of course not. Don't try to bait me or paint me as some kind of anti-Semite. No idea what you're talking about, still. "Inferiority" has no meaning in regards to biology. Just the observation that genocides don't occur because people are threatened, but because people are made to believe that they are threatened as a pretense to sieze the resources of another group. Look to the Sudan, to Darfur. What do you think the ganjaweed are after? They're not slaughtering a defenseless people because they fear them; they're slaughtering them in order to take their lands, livestock, and whatever else they want from a people it was convinient to get people to regard as some kind of threat. Still no idea what you're talking about here. "Weak in biological terms"? What does that even mean? What's your objective measure for "weakness"?Suppose we had a competition between Ewoks and allosaurs. Any one Ewok is no match for any one allosaur - the allosaurs have the superior strength, endurance, and ferocity - but many Ewoks can work together to build traps, leverage natural forces like gravity, and steal technology from the Rebel Alliance. No group of allosaurs can do the same thing no matter how many of them there are - they don't even have the forelimb stregth to manipulate their environment.Who is strong and who is weak? These words have no meaning in biology. Who is the more fit? Well, that depends on who wins. If the allosaurs wipe out the Ewoks, the allosaurs were clearly more fit. If the number of Ewoks comes to exceed the number of allosaurs, it must have been the Ewoks that were more fit. If your buddy has 20 kids that survive to adulthood, and you have 2, your buddy is more fit than you, no matter the fact that you work out at the gym and he sits on his butt and eats Cheetos. Still have no idea what you're talking about. I have a brain but it doesn't allow me to violate the laws of physics. It simply allows me to think ahead and use language. Well, there is some evidence to support it, like the lack of any "Neanderthal battlefields" or anything. And how did Homo sapiens kill off a species with a larger brain, bigger muscles, and possibly more developed culture in the first place? The idea that Homo sapiens extinguished the Neanderthal isn't immediately obvious. The idea that we simply merged genes with them is still plausible if the studies that claim no Neanderthal DNA are inconclusive. Probably not correct, but still plausible.