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Updated: Jun 23, 2026
12:14
Exploring Life History Choices: Using Temperature and Substrate Type as Interacting Factors for Blowfly Larval and Female Preferences
Published on: November 17, 2023
From stochastic environments to life histories and back
Shripad Tuljapurkar1, Jean-Michel Gaillard, Tim Coulson
1Department of Biology, Stanford University, Stanford, CA 94305-5020, USA. tulja@stanford.edu
Summary
Environmental variability influences life-history evolution, showing optimal phenotypes differ in fluctuating versus constant environments. Demographic factors like dispersion significantly impact fitness, affecting evolutionary trajectories.
Area of Science:
- Ecology
- Evolutionary Biology
- Population Dynamics
Background:
- Environmental stochasticity is a key driver of life-history evolution.
- Existing theories often simplify environments as constant, neglecting temporal variability.
- Understanding fitness in variable environments is crucial for evolutionary insights.
Purpose of the Study:
- To investigate life-history evolution under environmental variability.
- To decompose average individual fitness into vital rate contributions and temporal variations.
- To analyze how demographic traits influence fitness in fluctuating environments.
Main Methods:
- Decomposition of average individual fitness (stochastic growth rate) into vital rates and their variations.
- Analysis of stylized life histories incorporating generation time, demographic dispersion, and resilience.
- Examination of within- and between-year correlations in vital rates.
Main Results:
- Optimal phenotypes in fluctuating environments differ from those in constant environments.
- Demographic dispersion significantly impacts stochastic growth rates, even when deterministic rates are unaffected.
- Within- and between-year correlations, and serial correlations, have complex effects on fitness.
Conclusions:
- Environmental fluctuations necessitate a revised understanding of life-history evolution.
- Demographic dispersion is a critical factor in determining fitness in variable environments.
- The study provides a framework for developing life-history theory in non-constant environments.
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