A Comparison of Ecological and Morphological Overlap in a Peromyscus Community

The hypothesis that morphological structure of a community should reflect ecological structure (trophic relationships) was tested in this paper. An assemblage of closely related sympatric species of Peromyscus was studied to see how closely morphological structuring can describe actual food—use relationships in a community. Animals were collected during 4 different seasons and stomach contents were analyzed to reveal the diet of each species. A morphological analysis of the assemblage of Peromyscus was accomplished through the analysis of 4 external and 69 skeletal characters. Morphological and trophic relationships were computed using principal components and distance analysis. A positive relationship between morphological and ecological packing is shown by a correlation coefficient computed between food—use distances and morphological distances. Microhabitat use and foraging behavior are discussed in an attempt to expose actual mechanisms of competitive interactions.