Poly morphism

This is when the same species will be different colours,This is how they make sure the species will always survive,An example of this is the banded snail. They change colour depending on their habitat.For example on a woodland floor on various leaf litter, The snails that don't blend in as well on the leaf litter,will be predated by song thrushes.This is why on the leaf litter the brown snails will survive and the yellow ones will be predated.