Insects pollinate many of our crops, such as most orchard fruits, vegetables, and clover, which is an important livestock feed. Approximately a third of our food production depends on pollinator services, with insects, and particularly bees, doing most of the work (Buchmann & Nabham 1996, Free 1993, Ghazoul 2005, Klein et al. 2007). Most of the other direct services provided by insects are of relatively minor significance. While many people enjoy the honey produced by bee colonies, the use of insects themselves as food (entomophagy) is rather limited in humans (DeFoliart 1999, Menzel & D'Aluisio. 1998). Other insect products like lacquer and dyes from scale insects, beeswax, and silk from moth larvae support major industries, but none of these materials are essential to human welfare.
By far the most important benefits of insects to human societies are due to the ways they shape the world around us (Schowalter 2000, Waldbauer 2003). Without insects, most of our landscapes would look very different and would be much less hospitable to us and many other organisms. As herbivores, pollinators, and seed dispersers, insects have had an immense impact on the adaptive radiation of plants, particularly angiosperms (Grimaldi & Engel 2005). Their activities control many contemporary plant populations and affect the phenology and resource allocation of plants, thereby influencing the composition of plant communities (Weisser & Siemann 2000). Insects also participate in the decomposition of organic materials and thus facilitate the recycling of carbon, nitrogen, and other nutrients (Wardle 2002). In their absence, dung, carrion, dead wood, and leaf litter would accummulate in many terrestrial and aquatic environments. Many animals, including most vertebrates and spiders, rely heavily on insects in their diets, and as predators, parasitoids, and vectors of disease, insects control the populations of other animals (Thompson & Althoff 1999).