Some butterflies produce bad-tasting chemicals to prevent them from being eaten by birds. other butterflies
have evolved coloration that makes them look like the bad-tasting butterflies. if the mimic butterflies become
too numerous, then the bad-tasting butterflies will lose the protection they get by tasting bad, since most of
the butterflies that look like them taste good to birds, and birds will no longer be afraid to eat them. so, the
coloration pattern of the bad-tasting butterflies evolves over generations so they look less like the mimics.
when two species evolve in response to each other, this is an example of: