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Updated: Jul 24, 2026
20:36
Predicting the Effectiveness of Population Replacement Strategy Using Mathematical Modeling
Published on: July 4, 2007
Patterns of variance in stage-structured populations: evolutionary predictions and ecological implications
1Department of Ecology and Evolution, 1101 E. 57th Street, University of Chicago, Chicago, IL 60637, USA. cpfister@midway.uchicago.edu
Summary
Population growth rate variability can harm fitness. This study found that life history stages with high variation typically have low impact on population growth, suggesting natural selection favors stability.
Area of Science:
- Ecology
- Population Dynamics
- Evolutionary Biology
Background:
- Variability in population growth rate is often linked to reduced organism fitness.
- Matrix population models predict population growth rate variance based on variance and sensitivity of demographic rates.
Purpose of the Study:
- To investigate the relationship between the variance of demographic terms and their contribution to population growth rate.
- To test theoretical predictions regarding the drivers of population growth rate variance.
Main Methods:
- Analysis of stage-specific demographic data from 30 field populations across 17 published studies.
- Examination of correlations between temporal variance in demographic terms and their sensitivity/elasticity to population growth rate.
Main Results:
- No demographic matrix entry exhibited both high variability and a large effect on population growth rate.
- A predominantly negative correlation was observed between the temporal variance of a demographic term and its contribution to population growth.
- Sensitivities and elasticities of survivorship and growth consistently exceeded those of fecundity.
Conclusions:
- Natural selection appears to minimize population growth rate impacts from life history stages that are both highly variable and sensitive.
- Variable life history stages tend to contribute less to overall population growth rates.
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