ABSTRACT
Most insects start their life cycles with the fertilization of an egg, and they pass through either a complete or incomplete metamorphosis. Incomplete metamorphosis refers to insects such as roaches, body lice, and grasshoppers, that go through three developmental stages including egg, nymph, and adult stages. Mosquitoes, flies, and butterflies go through complete metamorphosis and pass through four developmental stages including egg, larvae, pupa, and adult stages. As insects grow and develop, they shed their protective exoskeleton while a new one develops underneath in a process called molting. The exoskeleton is a hard outer skin that protects internal organs and serves as an attachment site for muscles to provide movement. The hardened outer body wall of the exoskeleton may be covered with hairs, scales, or spines and is normally divided into segments joined by flexible intersegmental structures. In insects, these segments consist of a head, thorax, and abdomen as seen in Figure 6.2. Members of the order Arachnida have only one or two main segments as in ticks, mites, or spiders. The head usually contains mouth parts, antennae, large compound eyes and/or simple eyes. The numbers of eyes and antennae help to
Chapter 6 The Trouble with Pests
Whose Site? This web site was developed by Jun Fan, a graduate student in the entomology department at Virginia Tech. The work was supported by Dr. Nicholas D. Stone and Dr. Timothy P. Mack.
