Once upon a time there was a happy village of three headed werewolves. They were the same species but different colors, green purple and brown.
The purple and brown wolves lay many eggs during mating season while the green wolf only lays a few so when the monster comes to fee he is able to eat all the green eggs thus ending that type of wolf's species.
With only two species left and the monster still hungry he comes back for more food, but with the brown one having a natural camouflage the purple wolf is instantly spotted and eaten.
Luckily, the purple wolf layed many many eggs so although he may die his species will live for much longer.
With grass starting to grow in his previously muddy habitat, his position will soon be visible to the predator and his camouflage will no longer have any use, he must quickly adapt if he wants to survive.
Luckily, due to the necessity to either adapt or die, overtime the wolf was able to evolve wings to stay above the ground and prevent going extinct.