Venom organ failure. Many caterpillars have defensive venom glands associated with specialized bristles on the body, known as urticating hairs, which can be lethal to humans (e.g., that of the "Lonomia" moth), although the venom's strength varies depending on the species. Bees synthesize and employ an acidic venom (apitoxin) to cause pain in those that they sting to defend their hives and food stores, whereas wasps use a chemically different alkaline venom designed to paralyze prey, so it can be stored alive in the food chambers of their young. The use of venom is much more widespread than just these examples.
Evolution of snake venom model described above, in which genes in other body tissues are duplicated and then recruited to the venom gland before natural selection for toxicity. However, in 2014 a new model was proposed in which salivary protein genes are duplicated and then restricted to the venom gland. This model does away with the recruitment hypothesis and cites the homology between certain venom and body genes as unrelated in the linear fashion described in the traditional birth-and-death model. Gene duplication is not the only way that venom has become more diverse. There have been instances of new venom proteins generated by alternative