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Sampling species abundance distributions: resolving the veil-line debate
1Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08540, USA. chisholm@princeton.edu
Journal of Theoretical Biology
|May 18, 2007
Summary
This study reconciles ecological species abundance distribution (SAD) theories by examining sampling scales. It demonstrates that the log-normal distribution remains a plausible model, refuting claims based solely on sampling arguments.
Area of Science:
- Ecology
- Theoretical Ecology
- Mathematical Biology
Background:
- Preston's theory of species abundance distributions (SADs) is a foundational concept in ecology.
- Dewdney challenged Preston's veil-line concept, suggesting flaws in sample SAD analysis.
- Discrepancies exist regarding the interpretation of sample SAD shapes and their underlying distributions.
Purpose of the Study:
- To reconcile conflicting theories on species abundance distributions (SADs) proposed by Preston and Dewdney.
- To investigate the mathematical impact of logarithmic versus linear abundance scales on sampling.
- To re-evaluate the validity of the log-normal distribution as a species abundance model.
Main Methods:
- Mathematical analysis of sampling processes on different abundance scales (logarithmic and linear).
- Comparison of Preston's and Dewdney's theoretical frameworks.
- Derivation of new results concerning SAD sampling properties.
Main Results:
- Preston's and Dewdney's theories can be reconciled by accounting for the mathematical properties of sampling on logarithmic and linear scales.
- Sampling arguments alone are insufficient to reject the log-normal distribution as a plausible species abundance distribution.
- New insights into the behavior of sample SADs under different scaling assumptions were derived.
Conclusions:
- The log-normal distribution remains a viable model for species abundance distributions.
- Sampling methodology and scale (logarithmic vs. linear) are critical factors in interpreting species abundance data.
- Dewdney's critique of the log-normal distribution based solely on sampling is not universally supported.
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