Don't forget, there is occasionally a big fuckup in the DNA replication that can create something either incapable of life--or something that is MORE capable. These lead to the occasional jumps in evolution, sometimes called macroevolution. Experiments have shown that certain variations in critical genes in common housefly DNA result in a radically altered body structure, one that looks extremely similar to a dragonfly. This experiment has also been tried on dragonflies, ending up with something that is more similar to a housefly. (I've tried to find a link, but I forgot my source. Amateur, I know, but I wasn't studying up for a discussion, just reading for pleasure. Just like yall to know i'm not just bullshitting, scout's honor)