PARENT SESSION
Contributed Oral Session 92: Biodiversity: Aquatic Systems
Wednesday, August 10, 1:30 PM - 5:00 PM, Meeting Room 513 C, Level 5, Palais des congrès de Montréal
Do phylogenetic relationships explain patterns of diversity among north-temperate lakes?
Helmus, Matthew*,1, Bland, Thomas1, Williams, Christopher2, Ives, Anthony1, 1 Department of Zoology, University of Wisconsin, Madison, WI2 Department of Entomology & Wildlife Ecology, University of Delaware, Newark, DE
ABSTRACT- When studies explore patterns of biodiversity in nature, or assess how human impacts alter diversity, the measured response variable is usually species richness. However, species richness does not account for phylogenetic relatedness among species. Phylogenetic relatedness may be important because it correlates with functional diversity, and because the goal of many conservation programs is to protect a phylogenetically distinctive species. Here we (i) present a simple method to incorporate phylogenetic diversity in a measure of biodiversity and (ii) use this method to illustrate spatial patterns of biodiversity for three taxonomic groups (fish, shoreline trees and macrophytes) associated with 60 temperate lakes of northern Wisconsin. These lakes were sampled across gradients of landscape position, a proxy for lake productivity, and human development. We demonstrate that fishes were phylogenetically clustered, meaning that lakes tended to contain subsets of phylogenetically related species. This suggests environmental filtering, in which phylogenetically similar species have similar requirements and therefore occur in similar lakes. In contrast, trees and macrophytes showed little phylogenetic clustering. We also explore which environmental variables may be responsible for the phylogenetic clustering of fishes. Our results suggest that naturally occurring patterns of species diversity, and anthropogenic alteration of those patterns many be understood from consideration of the phylogenetic relationships among species.
Key words: community phylogeny, north temperate lakes, plant biodiversity, fish biodiversity