In preparation for egg laying, they construct a protected "nest" (some species dig nests in the ground, while others use pre-existing holes) and then stock it with captured insects. Typically, the prey are left alive, but
paralyzed by
wasp toxins. The wasps lay their eggs in the provisioned nest and the wasp
larvae feed on the paralyzed insects as they develop. The great golden digger wasp (
Sphex ichneumoneus) is found in North America. The developing wasps spend the winter in their nest. When the new generation of adults emerge, they contain the genetically programmed behaviors required to carry out another season of nest building. During the summer, a female might build as many as six nests, each with several compartments for her eggs. The building and provisioning of the nests takes place in a stereotypical, step-by-step fashion.
The Sphex Wasp Experiment Sphex has been shown, as in some
Jean-Henri Fabre studies, not to count how many crickets it collects for its nest. Although the wasp instinctively searches for four crickets, it cannot take into account a lost cricket, whether the cricket has been lost to ants or flies or simply been misplaced.
Sphex drags its cricket prey towards its burrow by the antennae; if the antennae of the cricket are cut off, the wasp would not think to continue to pull its prey by a leg. The navigation abilities of
Sphex were studied by the ethologist
Niko Tinbergen.
Richard Dawkins and
Jane Brockmann later studied female rivalry over nesting holes in
Sphex ichneumoneus. == Use in philosophy ==