Another fish, the sabre-toothed blenny, mimics the color and behavior of the harmless cleaner wrasse, which feeds on parasites attached to other fish. The blenny uses this resemblance to get close enough to its prey to attack it before it can recognize the deception. The European cuckoo exhibits a type of parasitic mimicry. It lays its eggs in the nest of a bird whose eggs are similar in appearance. The host bird then raises the cuckoo's young.
Mimicry is the product of natural selection.
Mimicking organisms have developed their particular similarities over time. Each step of the organism's transition has given it some slight advantage that has increased its chances for survival. For example, a change in coloration that allows a predator to camouflage itself may increase its chances of sneaking up on its prey. Thus it is able to acquire more food and increase its chances of staying healthy, surviving, and reproducing. Evolutionary biologists have used mimicry as a research tool and to help prove Charles Darwin's theory of evolution.