winter wrote:Also, I don't think anyone mentioned this, but, isn't it possible for all the current species to have come from a more basic selection of species? Or is this not possible? For example: breeding. Isn't that kind of the idea?
No. The definition of "species" is two organisms able to produce viable offspring. The "viable" part is key. You can breed a lion and a tiger, but their offspring are infertile (i.e., not viable). Thus, lions and tigers are two separate species.
Obviously, all species originate from a common ancestor, and that is what evolution is all about. The previous ancestor was not necessarily "more basic", it just had different selection pressures on it. Humans and chimpanzees are 98.77% identical at the DNA level (and we can calculate this _exactly_ because we have now sequenced the genomes of these two different, but clearly related, species). You can not "breed" humans and chimpanzees.
The creationists and IDers claim that "macroevolution" can occur and does not contradict their "theory" (not really a scientific one, since we can not test it). However, if we can (and we do) produce a Tree of Life showing how all species are related and how they all point to a common ancestor, then it shows that the theory of evolution is amazingly (and quite elegantly) good at describing our observations.
The creationists can not have it both ways. Either Noah took all 10 million+ species on board his little ship and evolution has not occurred since then (which they do claim), or the story of Noah is nothing but a demonstrably false mythology.