Actually, new species can arise very quickly. 1 2 Also, species can arise exponentially as they diversify (i.e., 960 becomes 1920, 1920 becomes 3840, 3840 becomes 7680, etc., etc.). Thus, there is no reason why all the species that we observe today descended from the few kinds on the Ark.
The animals on the Ark had a lot of genetic diversity still programmed into their genes. The more animals speciate, the more information they lose genetically. For instance, a purebred dog has less genetic diversity than a wild wolf. This is why breeders need to be careful to maintain what diversity is still left in the genes of purebreds. Actually, this fact argues against evolution, since the genetic tendency of animals during speciation is downward.
Site Under Construction
This site is still under construction. It needs more references, citations, and debate arguments. If you would like to help, please view the community page.
Dawkins, R. (2004). The Ancestor's Tale: A Pilgrimage to the Dawn of Evolution. Boston: Houghton Mifflin.
Sarfati, J. D., & Matthews, M. (1999). Refuting Evolution. Green Forest, AR: Master Books.