The hummingbird receives nectar from the flower, and in return the flower is pollinated by the hummingbird.

This Caribbean hermit crab (coenobita clypeatus) uses the shell of a dead snail for protection against its predators.

Bed bugs (Cimex lectularius) are small insects that interact with animals, including humans, and feed on their blood.

The cowbird chick on the left is being fed by the adult sparrow. Cowbirds trick sparrows into caring for their young by removing one of the sparrow’s eggs from its nest and leaving their own in its place.

The golden ground beetle is provided nutrition by the worms that it preys on.