Here's why Creatards might be right

[TheRocketSurgeon]

It works like this. All chemistry says is "this chemical (DNA, in the modern world, but coming from simpler versions of self-replicators that came before) can self-replicate. Sometimes the replication happens in a way that produces new variants. The environment may treat those variants differently, for better or worse. One example of "better" is a self-replicator that didn't need to be safely harbored in a protective lipid coat, but coded for its own coat. When the code is better, it is going to be favored for reproduction until that becomes a much more common variant. In large populations of self-reproducing DNA critters, some will become so different from one another that they can no longer share DNA, if they are sexually-reproducing creatures. If they are asexual and simply spawn exact copies, then there will still be variation among those copies sufficient that groups will wind up different because of the offspring of the oddballs. By these mechanisms over many generations, you get different species, all from passing the same DNA from parent-to-child, with variation."

The only "blueprint" is that there exists a chemical combination that, once formed, is capable of reproducing itself chemically. As variation continued on this theme, we wound up with billions of different combinations of this self-replicating molecule, which we see as different animal carriers for the molecule. You're confusing the game with the program, in the above metaphor, but in this case the only program is the relatively simple laws of chemistry, based on how atoms work together. If you wish to think that a Designer made the universe in such a way that chemicals could naturally do this, fine... but don't confuse the randomness of evolution with a Grand Plan. Any detailed study of nature shows that it, "red in tooth and claw", is anything but orderly. It is death and competition at every level, and cares nothing for the troubles of the lamb being eaten by the lion, or the protist consuming the bacterium, or the bacteria which die off until some of them randomly stumble upon the "recipe" for digesting nylon.