Conservação filogenética de nichos ambientais em mamíferos

quinta-feira, janeiro 06, 2011

Phylogenetic conservatism of environmental niches in mammals

Natalie Cooper1,*†, Rob P. Freckleton2 and Walter Jetz1

+Author Affiliations

1Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT 06520-8106, USA
2Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK

* Author for correspondence (nataliecooper@fas.harvard.edu).

↵† Present address: Department of Human Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA.

Abstract

Phylogenetic niche conservatism is the pattern where close relatives occupy similar niches, whereas distant relatives are more dissimilar. We suggest that niche conservatism will vary across clades in relation to their characteristics. Specifically, we investigate how conservatism of environmental niches varies among mammals according to their latitude, range size, body size and specialization. We use the Brownian rate parameter, σ2, to measure the rate of evolution in key variables related to the ecological niche and define the more conserved group as the one with the slower rate of evolution. We find that tropical, small-ranged and specialized mammals have more conserved thermal niches than temperate, large-ranged or generalized mammals. Partitioning niche conservatism into its spatial and phylogenetic components, we find that spatial effects on niche variables are generally greater than phylogenetic effects. This suggests that recent evolution and dispersal have more influence on species' niches than more distant evolutionary events. These results have implications for our understanding of the role of niche conservatism in species richness patterns and for gauging the potential for species to adapt to global change.

environmental niche, temperature, precipitation, Brownian rate parameter, space, phylogeny

Received October 12, 2010.
Accepted December 3, 2010.

This Journal is © 2011 The Royal Society

This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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