Bees, or Anthophila, are basically vegetarian wasps. Most bees collect pollen to provision their larvae; the food is stored in a nest. Whenever such a resource is reliably present, organisms will evolve to profit from such resources. Since bees store reliably pollen, species have evolved that capitalize on these resources. Among the species that evolved to exploit the pollen hoarded by bees are kleptoparasitic bees - remarkably many even. The photos below show a selection of kleptoparasitic bee species, together with their (possible) host.