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06:00
Experimental Manipulation of Body Size to Estimate Morphological Scaling Relationships in Drosophila
Published on: October 1, 2011
Body size evolution in mammals: complexity in tempo and mode
1Division of Biology, Imperial College London, Silwood Park Campus, Ascot, Berkshire SL5 7PY, United Kingdom. natalie.cooper@yale.edu
The American Naturalist
|April 17, 2010
Summary
Mammalian body size evolution shows an early burst of change, followed by slower diversification. Environmental factors like climate and geography significantly influence these evolutionary rates across ecoregions.
Area of Science:
- Macroevolution
- Macroecology
- Mammalian Biology
Background:
- Body size is a fundamental trait influencing species biology.
- Understanding body size evolution is crucial for macroevolutionary and macroecological studies.
Purpose of the Study:
- To model the tempo and mode of mammalian body mass evolution.
- To identify key predictors of body mass evolution rates across ecoregions.
Main Methods:
- Utilized body mass data for 3,473 mammalian species.
- Employed a near-complete mammalian phylogeny.
- Applied spatial models to analyze evolutionary rates within ecoregions.
Main Results:
- An early-burst model best describes mammalian body mass evolution, indicating an initial rapid diversification phase.
- Approximately 50% of the variation in body mass evolution rates is explained by a few predictors.
- High evolutionary rates correlate with cold, low-lying, species-poor, high-energy, mainland ecoregions.
Conclusions:
- Mammalian body size evolution is characterized by an early burst followed by slower change.
- Geography, climate, and historical factors interact to shape mammalian body size evolution.
- Environmental predictors significantly influence the rates of body mass evolution across different ecoregions.
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