You are never to young for a meta-costume*.
To the untrained eye, it may look like my daughter is dressed as a monarch butterfly for Halloween. To the trained eye, you will recognize that half of her parental set is extremely dorky.
She is actually going as the concept of Müllerian Mimicry instantiated in the form of a viceroy butterfly. This costume is occassionally mistaken for Batesian Mimicry by novices.
Batesian Mimicry is probably the better known version of mimicry, in which a harmless species mimics the warning signal to predators of a poisonus or species in order to gain protection from predation. The similar color pattern on certain king snakes, which approximate the color pattern on venomous coral snakes, is a well known example.
Müllerian Mimicry occurs when two poisonous or venomous species evolve similar warning signals to predators. The idea is that adopting the same warning signal will reinforce the signal’s meaning to predators.
The color pattern of a viceroy butterfly was long thought to be an example of Batesian mimicry. Monarch butterflies retain compounds from the milkweed plant they eat as caterpillars, making them unappetizing to birds. Viceroy butterflies were thought to mimic the warning signal of monarchs to gain protection from predators.
More recent (ie, within the past 25 years), sophisticated, and less well-known experiments have shown, however, that birds do not find viceory butterfiles appealing either, even when the warning signals are taken out of the equation – moving the similarity between monarch and viceory butterfly wing patterns out of the Batesian camp and into the Müllerian* and making my daughter’s costume a walking, sugar-overdosed lesson in evolutionary biology.
*Costumes themselves can be considered a form of mimicry. So, what else would you call a costume that comments on mimicry other than meta?
**This in no way reflects the opinion of my family or of the butterflies in regard to certain popular characters on Downton Abbey.
The Finch and Pea 