Insects

Abstract

There are very many more species of insect which are herbivores than there are of any other taxonomic group of animals (there are very many more insects than there are all other sorts of animals). What is more there are species of insects specialized to feed on every conceivable species of plant; and on all different parts of plants. Any attempt to systematically review this entire vast array would be at best unwieldy, and ultimately tedious. However, there is no need for such extremes. The evidence for the generality of a relative shortage of nitrogen in the food of herbivorous insects is everywhere apparent. I can best illustrate this generality, and the adaptations that have evolved to alleviate the shortage, by taking examples from broad groupings of species according to what they eat and how they eat it.