Lots of caterpillars and other tiny animals have “eyespots” on their bodies that they use to frighten or distract predators or even make themselves look like something bigger and scarier. In Costa Rica, scientists have found two species that take things a step further and can “blink” their eyespots for a more realistic effect.
Both caterpillars can "blink" their posterior eyespot upon perceiving a threat. That is, they can move the skin around the eyespot such it either conceals/reveals the eyespot or flashes (i.e. reflects light) conspicuously towards an onlooker. Interestingly, both Eumorpha caterpillars also inflate their thoracic body segments, while pulling their head into their body, to form a diamond shape which appears similar to the head shape of dangerous co-occurring snakes (at least to human observers). [Caterpillar Eyespots]