A type of wasp that is native to Finland has adapted to make clever use of spider silk. The genus known as Clistopyga lays its eggs inside the dead bodies of jumping spiders. This seems like a strange place to lay eggs, but it turns out that wasps don’t have much to choose from when it comes to finding shelter for their babies. In order to ensure the safety of their larvae these wasps add insult to injury by stealing the jumping spider’s silk after paralyzing the jumping spider with their venom.
The stinger of this type of wasp has many uses. First the wasp will find a jumping spider that it can lay its eggs inside of. Then they immobilize and slowly kill the jumping spider with its venom. Next the wasp will use its stinger to stab the jumping spider in order to lay its eggs inside the spider’s fresh wound. However, the wasp eggs are still vulnerable to predators, as they are not completely shielded from the environment. To fix this problem the wasp rummages through the spider’s nest looking for bits of spider silk, which it then uses to sew up the wound. Once the wound is completely sewed up, the wasp larvae is sure not to be removed from the jumping spiders body cavity. This cruel, yet sophisticated, behavior is pretty impressive considering that a wasp has a brain smaller than a pinpoint.
Why would wasps prefer to store their larvae inside of a jumping spider’s corpse as opposed to finding other forms of shelter? And why a jumping spider and not another type of spider?