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Population diversity: its extent and extinction
J B Hughes1, G C Daily, P R Ehrlich
1Department of Biological Sciences, Stanford University, Stanford, CA 94305-5020, USA.
Science (New York, N.Y.)
|October 24, 1997
Summary
Globally, there are an estimated 1.1 to 6.6 billion species populations. Habitat loss is destroying approximately 1800 populations per hour in tropical forests alone.
Area of Science:
- Ecology and Conservation Biology
- Biodiversity Estimation
- Population Genetics
Background:
- Genetically distinct populations are crucial for maintaining overall biodiversity.
- Understanding population numbers is essential for effective conservation strategies.
- Previous estimates of global population numbers have been lacking.
Purpose of the Study:
- To estimate the global number of genetically distinct populations across various species.
- To quantify the rate of population extinction due to habitat loss, particularly in tropical forests.
Main Methods:
- Literature review on population differentiation to determine populations per area for sample species.
- Analysis of species distribution maps to calculate average species range area.
- Extrapolation of findings to estimate global population numbers and extinction rates.
Main Results:
- An estimated 220 genetically distinct populations exist per species.
- This equates to a global estimate of 1.1 to 6.6 billion populations.
- Approximately 1800 populations are lost per hour in tropical forests due to habitat loss.
Conclusions:
- The study provides a novel quantitative estimate of global species populations.
- Habitat loss poses a severe and rapid threat to global biodiversity, with millions of populations lost annually.
- Urgent conservation efforts are needed to mitigate population extinction, especially in tropical ecosystems.
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