ROARK, Alison M.*; BJORNDAL, Karen A.; Univ. of Florida, Dept. of Zoology; Univ. of Florida, Dept. of Zoology: Experimentally imposed patterns of food availability and their effects on metabolic rate in Indian stick insects, Carausius morosus

Changes in food availability throughout an animal�s lifetime may drastically influence physiology and life history. In this study, we sought to elucidate the effects of different patterns of intake and growth on metabolic rates of Indian stick insects, Carausius morosus. C. morosus were individually maintained on a diet consisting of leaf discs cut from English ivy, Hedera helix. These leaf discs were offered to each insect either ad libitum or in quantities equal to 60% of average ad libitum intake on a mass- and instar-specific basis. Insects were fed according to one of six treatment regimens: continuously ad libitum, continuously restricted, ad libitum until either the beginning of the fifth instar or first oviposition followed by restricted feeding, or restricted until either the beginning of the fifth instar or first oviposition followed by ad libitum feeding. Oxygen consumption rates of these insects were assessed during each of several instars and during adulthood using Scholander respirometers. Insects experiencing different intake patterns exhibited significantly different mass-specific metabolic rates. These results have important implications for life histories in these animals.