Phylogenetic Methods in Ecology

Abstract

AbstractPhylogenetic comparative methods, incorporating patterns of similarity among close relatives, are an important tool in the ecological research. In tests of adaptive hypotheses, examining interspecific correlations between traits and environmental conditions, independent contrasts and related methods address the statistical nonindependence among species due to common ancestry. In community ecology, patterns of co‐occurence among related species provide insights into community assembly processes. In conservation biology, phylogenetic diversity can be an important assessment tool to prioritize species assemblages. Developments in phyloinformatics and improved phylogenies for different groups will promote expanded use of comparative methods in many areas of ecology.Key conceptsComparative biology focuses on similarities and differences among species to test hypotheses in ecology, evolutionary biology and related fields.Closely related species tend to be ecologically similar, reflecting their descent from a common ancestor. This similarity must be considered in tests of adaptive correlations between organismal traits and environmental conditions, as it can create statistical nonindependence among species.The method of phylogenetic independent contrasts, which compares trait values of related species across a phylogeny, provides a robust method to address the nonindependence of species and is widely used in ecology.A variety of processes influence the assembly of ecological communities. Communities may be composed of species that are ecologically similar, reflecting shared adaptations to the environment (known as environmental filtering), or species that are ecologically distinct, as predicted if biotic interactions such as competition or facilitation play an important role.The study of phylogenetic community structure – the degree of relatedness of co‐occurring species – provides insight into the processes influencing community assembly. Co‐occurrence of close relatives is likely caused by environmental filtering, whereas a variety of processes may lead to co‐occurrence of more distant relatives, including competition, facilitation and convergent evolution.Phylogenetic diversity – which can be measured as the sum of the branch lengths in a phylogeny – provides a valuable tool in conservation biology. Targeting areas with high phylogenetic diversity may be an efficient means to maximize conservation of taxa with high diversity of ecological and economic features.Phylogenetic approaches are an important tool to integrate ecological and evolutionary processes across a range of temporal and spatial scales.