Food and Microhabitat Utilization by Grasshoppers from Arid Grasslands: Comparisons with Neutral Models

Abstract

Patterns of food and microhabitat use in arid grassland grasshopper communities are examined by comparing actual resource use with neutral models. A variety of neutral models is included in the analysis ranging from completely randomized resource utilization to models retaining much of the original community structure. Comparisons with resource utilization which are completely randomized indicate that biotic interactions are present for both diet and microhabitat niche dimensions. Average similarity in resource use of actual communities is much lower than in the analogous, completely randomized communities which suggests resource utilization by these species is hyperdispersed (on the average). However, mean niche overlap is not as low as possible which suggests other factors such as phylogenetic constraints on resource use or coevolved interactions which affect overall use of resources by a community are important.