The outcome of many high order processes in ecology depends on the way in which the abundance and distribution of plants affects the eating rate of plants by animals. However, mechanistic models describing the operation of the functional response of herbivores have failed to emerge apart from those developed for predators. The P.I. offer new models describing the effects of spatial and morphological characteristics of plants on the intake rate of plant tissue by vertebrate herbivores. Their models depart from the Type II response represented in Holling's disc equation by assuming that searching for food and processing it are complementary rather than exclusive activities. Their hypothesize that the parameters in our models should follow allometric relationships for linear and surface dimensions of animals. The P.I.'s conduct a randomized complete block experiment with a factorial layout to test the predictions of our models and to describe the allometric scaling that governs their behavior. Factors in the experiment will include animal body size, as well as plant bite size and biomass. The investigator will observe responses to these treatments in vertebrate herbivores ranging in mass over five orders of magnitude. The results will serve as a foundation for future development of a comprehensive model of feeding behavior in these animals.
