Historical ecology of Amazonian lizards: implications for community ecology

Nineteen species of lizards simultaneously studied at the Curua-Una in the central Amazon of Brazil separate on the basis of microhabitat use and prey types. There is no relationship between microhabitat niche breadths and di etary niche breadths, species using the greatest diversity of microhabitats do not necessarily use the greatest diversity of prey types. A pseudocommu nity analysis revealed that the lizard assemblage is structured with respec t to microhabitat and diets. A comparison of dietary overlaps with phylogen etic similarities indicates that much of the variation in dietary similarit y in this assemblage is associated with phylogenetic similarity. A similar analysis with microhabitat overlaps yielded no relationship to phylogenetic similarity. These results suggest that much of the structure in this parti cular assemblage is historical, i.e., not the direct result of ongoing spec ies interactions at the local level. Because this assemblage is comprised o f lizards from a diversity of higher taxa (families). we suggest that histo rical factors may be more important in determining structure in phylogeneti cally deeply rooted assemblages than in phylogenetically shallow-rooted ass emblages.