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A common tendency for phylogenetic overdispersion in mammalian assemblages
Natalie Cooper1, Jesús Rodríguez, Andy Purvis
1Division of Biology, Imperial College London, Silwood Park, Ascot, Berkshire, UK. natalie.cooper04@imperial.ac.uk
Proceedings. Biological Sciences
|May 30, 2008
Summary
Mammal communities show phylogenetic overdispersion, meaning species are more distantly related than expected. This suggests competition or habitat filtering shapes mammalian assemblages, impacting species coexistence.
Area of Science:
- Ecology
- Evolutionary Biology
- Mammalogy
Background:
- Competition is a key factor structuring mammalian communities.
- Phylogenetic dimensions of competition were historically challenging to study.
- Recent advances in phylogenetic data enable detailed community structure analysis.
Purpose of the Study:
- To investigate the phylogenetic structure of mammalian assemblages.
- To determine if competition leaves an imprint on community relatedness.
- To test for phylogenetic overdispersion in New World monkeys, North American ground squirrels, and Australasian possums.
Main Methods:
- Analyzed 142 mammalian assemblages across three distinct clades.
- Utilized phylogenetic data to assess species relatedness within assemblages.
- Compared observed phylogenetic structure to null models to detect significant patterns.
Main Results:
- Mammalian assemblages exhibited significant phylogenetic overdispersion.
- Species within assemblages were more distantly related than predicted by chance.
- Overdispersion was significant in monkeys and squirrels, but not possums.
Conclusions:
- Widespread phylogenetic overdispersion in mammal assemblages is demonstrated.
- Findings imply significant roles for competition and/or habitat filtering in structuring communities.
- These processes may favor distantly related species or those with convergent traits.
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