Arthropods, including crustaceans, grow by molting. The individual makes a protective body covering, or exoskeleton, underneath its old exoskeleton, and then crawls out of the old protective exoskeleton while the new one is still soft and pliable. The soft shell crab is a familiar example of an arthropod in this condition. At this stage the animal can enlarge within the shell. Finally the shell hardens again into its protective form. Arthropods are of major interest in the world environment, not to say the world's economy, since they make up 7/8 of all species of animals. Three-fourths of them are insects; nearly all of the rest are arachnids (spiders, scorpians) and crustaceans (shrimps, lobsters, crabs). Dr. Skinner has devised a method for controlling the timing of molting in crustaceans. Working with a land crab as typical of this class of animals, her laboratory proposes to explore the biochemistry of molting, with emphasis on the formation of the shell and associated structures. They will also explore the regulatory events associated with molting: the hormonal controls, and the activation of specific genes. In addition, the experiments will examine the generality of molting processes by looking for biochemical cross-relatedness with similar processes taking place in insects. The understanding of these basic physiological activities is not only of interest and importance in its own right, but is useful knowledge for such human-related purposes as expanding the food supply and, conversely, the development of environmentally acceptable pest controls.
