THE CINEREOUS MOURNER, a bird that lives in the rainforests of Peru, does a terrible job guarding its chicks. Luckily, the chicks don’t need their parents’ help. The young birds look like toxic caterpillars that live nearby—they’re about the same size and color, with spiky orange feathers that have white tips. Not only that, but they move like the caterpillars too.
This is probably an example of Batesian mimicry, where a harmless animal evolves to look like a dangerous one. For example, the non-venomous king snake looks enough like the venomous coral snake that predators stay away. Frogs mimic each other, and so do many insects, but until now, no one has discovered a case of a bird mimicking an insect.…
