The embedded clip starts with one primitive Homer organism, and ends with another. It’s just over a minute from the opening of a recent Simpsons episode, Homerazzi.
I didn’t see the episode itself. I haven’t seen much Simpsons since becoming a dad, and what I have seen suggests that the show has fallen a long way from its lofty perch amidst the highest branches of the tree of USA culture.
I found a slightly longer version of this clip at an intelligent design blog, which I in turn found via reddit. The comments at reddit range over The Simpsons, evolution, design, Fatboy Slim, etc.