Bodyguards have a tough and risky job but they usually get paid for their trouble. But not the caterpillar of the geometer moth. Against its will, it is recruited to defend the developing young of a parasitic wasp, and the only 'reward' it gets for its trouble is to be eaten inside out by the larvae of its attacker.
The vast majority of wasps are "parasitoids", animals that practice the grisly art of body-snatching. They lay their eggs in the bodies of other living animals to provide their newly hatched grubs with a fresh supply of meat. Like HR Giger's alien, the full-grown larvae then burst through their host's skin, usually killing it in the process.
But the fate of one type of caterpillar Thyrinteina leucocerae doesn't end there. It is targeted by a Glyptapanteles wasp that, on a single pass, can lay as many as 80 eggs onto the ...
