Creationists reason that there are real limitations to genetic changes and that this indicates a special creation of each major category of life forms. Each new life form came into being by an act of intelligent intervention specifying its genetic information for its peculiar function. Just as letter sequences make up different words, DNA codes vary and produce different species. If it requires intelligence to create King Lear from selecting and sorting the words in a dictionary, then it also requires intelligence to select and sort genetic information to produce a variety of species which work together as a system in nature. The sudden appearance of these life forms only strengthens our case that a supernatural intelligence was at work to accomplish this organization. By the principle of uniformity, this is the most plausible solution to the problem.
Now that we have new evidence about the nature of the universe, the information stored in DNA molecules, and further fossil confirmation, the words of Louis Agassiz resound even more loudly than they did when first written in 1860: "[Darwin] has lost sight of the most striking of the features, and the one which pervades the whole, namely, that there runs throughout Nature unmistakable evidence of thought, corresponding to the mental operations of our own mind, and therefore intelligible to us as thinking beings, and unaccountable on any other basis than that they owe their existence to the working of intelligence; and no theory that overlooks this element can be true to nature." [Louis Agassiz, "Contribution to the Natural History of the United States" in American Journal of Science, 1860]
There are two views of origins. One says that everything came about by natural causes; the other looks to a supernatural cause. The overwhelming evidence supports the Creationist view.