Most all apes did die out.
I once heard that if you took every non-human great ape in the world, they would not fill a single football-sized stadium, while humans would fill 60,000 stadiums, filling another 1,000 every year.
The fact is, great-apes which survive today do so only in areas which were never densely inhabited by humans.
Also, if everything is always survival of the fittest, then how does one explain symbiotic relationships? And in such relationships where both partners are dependent on one another for survival, which one came first?
Also, life could never have originated by chemical means. Scientists still don't know how life originated, because it's origin still cannot be explained. Matter of fact, in the 1970s, Sir Frederick Hoyle calculated that the probability of spontaneous generation of a single cell organism was one chance in 10 to the 40,000 power. To put this in perspective, if an event has the probability of one chance in 10 to the 50th power, it is considered a mathematical impossibility. This fact, Hoyle stated, is "enough to bury Darwin and the whole theory of evolution. There was no primeval soup, neither on this planet nor on any other, and if the beginnings of life were not random they must therefore have been the product of purposeful intelligence."
George Wald, a prominent atheist said:
"When it comes to the origin of life there are only two possibilities: Creation or spontaneous generation. There is no third way. Spontaneous generation was disproved one hundred years ago, but that leads us to only one other conclusion, that of supernatural creation. We cannot accept that on philosophical grounds; therefore we chose to believe the impossible: That life arose spontaneously by chance!"
"I do not want believe in God. Therefore I chose to believe in that which I know is scientifically impossible, spontaneous generation leading to evolution."