Quote from: Dudeman on August 21, 2015, 09:33:04 AMThe main problem with the theory of evolution is that at the core of the theory is the assumption that an animal can mutate to the point where it becomes its own species. This, by the natural selection argument, could never be possible. Two animals of different species can never produce fertile offspring. Mules and ligers, for example, can never have baby mules or baby ligers because they are hybrid animals. So, if an animal did get to the point where it mutated into its own species, it would no longer be able to produce fertile offspring. But according to natural selection, only good mutations should pass on. Not being able to reproduce seems like a pretty terrible mutation, don't you think? The mutant would then die off, and no species changes would ever take place, leaving a world full of one species of animal.
Of course, we know that's not the case.
You make the mistake of assuming that evolution happens instantly. That's wrong. It's a slow process. An animal doesn't just suddenly mutate into a new species.
For example, let's assume a species that has grey fur. Two groups of said species move to different environments. The first group moves to an environment that is entirely white. The other moves to an environment that is black. Eventually one of the animals in the white environment has a mutation that causes its fur to become slightly lighter. Now, being able to hide in their environment is an advantage for an animal. And as it turns out, this animal does not get eaten because it is more difficult to detect in the environment. This happy fellow then lives and reproduces, with this advantageous mutation being passed on to the next generation. Then in the next generation another specimen develops even lighter fur. And so on.
Fast-forward several generations and you have one group of animals with black fur and another with white. Now this is not limited to just the color of the fur, there are other advantageous mutations occurring in the species as well. The two groups do not mate with each other so the new genes are only propagating within one group. Eventually the two groups are genetically so different that they can no longer reproduce. If the required advantages in the two environments differ, you end up with two completely different kinds of animals.
When it comes to the life on earth, we are talking about millions of years here. That is a damn long time for random mutations to occur and cause species to diverge from each other.