Meeting Abstract

77.5  Monday, Jan. 6 09:15  Plant chemistry and temperature both influence host plant choice CLISSOLD, F.J.*; SIMPSON, S.J.; The University of Sydney; The University of Sydney fiona.clissold@sydney.edu.au

Fitness of herbivorous ectotherms is strongly influenced by temperature and diet, mediated via effects of temperature on metabolic rate. We have shown in the laboratory that, although metabolic rate increases with temperature, the most significant effect temperature has on life history outcomes in a model herbivore, the locust, is its influence on the rates and balance of protein and carbohydrate absorbed from particular host plants; i.e. host plant ‘quality’ is temperature dependent. Furthermore, locusts were able to choose body temperatures so that protein and carbohydrate were differentially absorbed to redress experimentally imposed nutrient imbalances. Here we demonstrate in the field that locusts choose to maximize growth at the cost of delaying adult maturity; thus in an ecological setting host plant choice is dependent on both temperature and host plant availability.