The Statistical Significance of Diets and Other Resource Utilization Patterns

The assessment of the statistical significance of differences in diets is surprisingly rare. In this note we discuss a powerful randomization test, that can be applied to diets as well as to other patterns of resource utilization and, for example, to patterns of species composition. We argue that ecological questions often require that both between-group overlaps and within-group overlaps are compared with their expected distribution under the null-hypothesis of no differences between groups.