Most species feed on fish caught by diving from flight, but the marsh terns are insect-eaters, and some large terns will supplement their diet with small land vertebrates.
And although the species is a widespread and devout insect-eater, some isolated populations of long-fingered bat have puzzled scientists by showing a proclivity towards fishing.
Mammals come in four kinds: insect-eaters (anteaters, for example), plant-eaters (koalas), fruit-eaters (squirrels) and omnivores (felines and most primates).
