Mimic means to copy, imitate, or resemble. In biological systems, when an animal looks or behaves like another animal, in order to deceive a third animal, it is said to be a mimic. Mimicry is usually a way to avoid being eaten and takes many forms. The best known examples of mimicry are when harmless animals (non-venomous or non-toxic) resemble venomous or toxic animals. Monarch and viceroy butterflies are excellent examples of this. Monarch butterflies, as caterpillars, eat the leaves of milkweed plants, which contain a toxic substance. The caterpillars retain the toxin in their own tissues, which makes them toxic or distasteful to predators. They remain toxic even after transforming into a butterfly. Adult viceroy butterflies strongly resemble monarchs, although they are not toxic or distasteful. Because of this mimicry of monarch color patterns, predators avoid eating viceroy butterflies. Interestingly, viceroy butterfly eggs and caterpillars also protect themselves from predation by looking like something else. The eggs resemble plant galls and caterpillars resemble bird droppings. There are many harmless flies that mimic the colors of venomous bees and wasps.
Crypsis is another way of avoiding predation. Crypsis is when animals resemble their backgrounds or substrates, making it more difficult to see them.