Homer's Evolution couch gag

Homer's Evolution is the longest couch gag ever used on the show. It starts with Homer as a single-celled organism and going through time to become the modern day Homer.

Plot
A single-celled organism, resembling Homer, separates into a lot of cells (all of them yelling "D'oh!") and eventually turns into a jellyfish and then into a fish-like creature and swims onto land, avoiding an octopus Mr. Burns who tries to catch him. As it grows legs and turns into a lizard that eats a dragonfly-like Lenny. He walks along and keeps evolving into a primitive mammal as he sees dinosaurs and a pterosaur resembling Agnes Skinner; a theropod resembling Bart tries to eat him, and a stegosaur resembling Lisa prevents Bart to eat Homer by snapping him with her tail. Homer continues jumping from tree to tree to become a monkey. He becomes a caveman walking in a snow storm, while a caveman Moe, devolves into a small, shrew-like animal as he walks to the other way. Caveman Homer then evolves into conquistador, then a pilgrim, goes through Victorian times and eventually becomes the modern Homer. He gets to his house and sits on the couch, when Marge asks him what took him so long. Homer then sighs in exhaustion.

Behind the Laughter
There are two versions of this that are no different until the end. When Marge asks Homer what took him so long, in one, he sighs. In another, instead of Marge asking him why took him so long, she asks him "Did you bring the milk?".

Character Appearances

 * Homer Simpson
 * Marge Simpson
 * Bart Simpson (also as a Tyrannosaurus)
 * Lisa Simpson (also as a Stegosaurus)
 * Maggie Simpson
 * Moe Szyslak (unevolving from a caveman to a rat)
 * Agnes Skinner (as a pterodactyl)
 * Mr. Burns (as an octopus)
 * Lenny (as a dragonfly)

Prehistoric Creatures

 * Single-Celled Organism (Homer)
 * Jellyfish (Homer)
 * Anomalocaris
 * Primitive Cephalophod (Dr. Burns)
 * Haikouicthys (Homer)
 * Amphibian-like Fish (Homer)
 * Proterogyrinus (Homer)
 * Dimetrodon (Homer)
 * Meganeura (Lenny)
 * Parasaurolophus
 * Brachiosaurus
 * Pteranodon (Agnes Skinner)
 * Tyrannosaurus Rex (Bart)
 * Stegosaurus (Lisa)
 * Didelphodon (Homer and Moe)
 * Bigger mammal (Homer)
 * Apidium (Homer and Moe)
 * Australophithechus (Homer and Moe)
 * Cro-Magnon (Homer and Moe)