Predatory caterpillars roam the greenery of Hawaii in search of snails to devour alive. An article in the journal Science reveals how tiny caterpillars of the species Hyposmocoma molluscivora creep up on snails and use their silk glands to spin a kind of web, sticking the snails to the leaves they are sitting on.
The caterpillar then starts eating the snail, following it all the way to the end of its shell. This predatory behaviour by a caterpillar seems to be unique to Hawaii. Authors of the paper, Daniel Rubinoff and William Haines, say, "Specialised predatory by lepidopteron larvae, an extremely rare phenomenon worldwide, has independently arisen at least twice in Hawaii." They speculate that the isolation of the island is important for the evolution of such novel traits.