Phylogenetic patterns of climatic, habitat and trophic niches in a European avian assemblage.
OBJECTIVE
The origins of ecological diversity in continental species assemblages have long intrigued biogeographers. We apply phylogenetic comparative analyses to disentangle the evolutionary patterns of ecological niches in an assemblage of European birds. We compare phylogenetic patterns in trophic, habitat and climatic niche components.


METHODS
Europe.


METHODS
From polygon range maps and handbook data we inferred the realized climatic, habitat and trophic niches of 405 species of breeding birds in Europe. We fitted Pagel's lambda and kappa statistics, and conducted analyses of disparity through time to compare temporal patterns of ecological diversification on all niche axes together. All observed patterns were compared with expectations based on neutral (Brownian) models of niche divergence.


RESULTS
In this assemblage, patterns of phylogenetic signal (lambda) suggest that related species resemble each other less in regard to their climatic and habitat niches than they do in their trophic niche. Kappa estimates show that ecological divergence does not gradually increase with divergence time, and that this punctualism is stronger in climatic niches than in habitat and trophic niches. Observed niche disparity markedly exceeds levels expected from a Brownian model of ecological diversification, thus providing no evidence for past phylogenetic niche conservatism in these multivariate niches. Levels of multivariate disparity are greatest for the climatic niche, followed by disparity of the habitat and the trophic niches.


CONCLUSIONS
Phylogenetic patterns in the three niche components differ within this avian assemblage. Variation in evolutionary rates (degree of gradualism, constancy through the tree) and/or non-random macroecological sampling probably lead here to differences in the phylogenetic structure of niche components. Testing hypotheses on the origin of these patterns requires more complete phylogenetic trees of the birds, and extended ecological data on different niche components for all bird species.
Landscape Dynamics Unit, Swiss Federal Research Institute WSL, Zürcherstrasse 111, CH-8903 Birmensdorf, Switzerland.
Peter B
PB
Pearman
Laboratoire d'Ecologie Alpine, UMR 5553, Université Grenoble I, CNRS, BP 53, F-38041 Grenoble Cedex 9, France.
Sébastien
S
Lavergne
Laboratoire d'Ecologie Alpine, UMR 5553, Université Grenoble I, CNRS, BP 53, F-38041 Grenoble Cedex 9, France.
Cristina
C
Roquet
Landscape Dynamics Unit, Swiss Federal Research Institute WSL, Zürcherstrasse 111, CH-8903 Birmensdorf, Switzerland.
Rafael
R
Wüest
Landscape Dynamics Unit, Swiss Federal Research Institute WSL, Zürcherstrasse 111, CH-8903 Birmensdorf, Switzerland.
Niklaus E
NE
Zimmermann
Laboratoire d'Ecologie Alpine, UMR 5553, Université Grenoble I, CNRS, BP 53, F-38041 Grenoble Cedex 9, France.
Wilfried
W
Thuiller
Birds; Brownian motion; Europe; comparative method; disparity through time; ecological diversification; macroecological sampling; niche conservatism; phylogenetic signal