> If humans really did evolve from human apes then why are there no
> human apes alive today (or well at least no known) ?
I don't understand this question. Homo sapiens (i.e., us) *ARE* a kind of ape. We are essentially a clever, hairless, bipedal variant of a chimpanzee (plus a few more differences here and there).
If you want to know what happened to our more ancient chimpanzee-like direct ancestors: they died of natural causes, and all the standard things that animals die from. Their genetic signature did not survive because of genetic drift and natural selection as the evolutionary theory explains.
Our genetic cousins, however, that's a far more complicated story ...
> How come the chimpanzees and the orangutangs and the gorillas
> survived until this day practically staying the same shape
> (I haven't got any information about the monkeys evolution in the
> past)
There is absolutely no evidence that other apes have not evolved. Actually, the mere fact that there are 4 types of gorillas and 2 types of Chimpanzees, by itself, indicates that there has been, and continues to be genetic drift among all of our ape cousins. For example, Chimps and Bonobos had a genetic split only about 1 million years ago (as compared to our split with that line 6 millions years ago.)
> While more advanced forms of semi humans died out ore evolved ?
The way evolution works is that similar species have to be competing for the exact same sources of food and the food has to be limited and one of the species has to have a measurable advantage over the other for one to have a likelihood of taking over and replacing the other.
Apes live and compete with each other in forest and jungle environments that our bipedal ancestors did not hang around in for very long. At some point (between ardipithecus and australopithecus, about 3.5 million years ago) our nearest ancestors with the chimpanzees left the forest and carved out a living on the Savanah. We did this, in part, because we *COULD* -- we evolved the ability to walk in an erect manner, which meant we could pursue food opportunities (probably as a scavenger) in the tall African grasses instead of the forest. We also switched diets from berries and insects to a diet that was largely pure meat.
So what happened is that as we started evolving radically giving us very unbalanced food gathering strategies versus our ancestors, we found that we were no longer competing with them, because we sought food sources elsewhere. (We became an "isolated group" -- Darwin explains this in "Origin of the Species".) On the other hand we *WERE* competing with saber-toothed cats for food and only one of us two has survived to this day.
> I mean. There is only 1 species of humans today.
Correct.
> I can get kids with anyone of the races i would like but there is
> really only one known. I think it doesn't make sense at all.
The other candidates for survival along the hominid line were Homo erectus, Homo neanderthalensis and Homo floresiensis. All three of those left Africa but one way or another could not survive in the long run. Probably some combination of climate change or other environment factors and inability to adapt to changing food sources did them in. In the case of neanderthalensis they came in direct contact with the slightly, but measurably, superior Homo sapiens that out-competed them directly for food where it was most available throughout Europe -- this forced them to try to eek out livings in areas where the food supply was not tempting enough for Homo sapiens to pursue, and it turned out to be not worth it for Neanderthalis either.
Oh and any hominid that remained in Africa would also have gotten its butt kicked by us emerging Homo sapiens.
While we humans have not yet demonstrated an ability to survive as long as some of our ancestors (Homo erectus lasted about a million and a half years) we are more immune to natural climate shifts by expanding our food gathering strategies to include farming and domestication. Our technological advantages also ensure that we will not be out-competed by some other animal and our food won't suddenly disappear from us for some reason beyond our control.
> How would the primitive apes have survied along side with the most
> advanced form of humans. While all the semi humans died out ?
As I explained, the other apes hung around in the forest, while we did not. As modern humans, we now have a need for the forest -- we may yet finish the job of eradicating all our ape cousins through the process of industrialization.
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