Global change, life-history complexity and the potential for evolutionary rescue

Area of Science:

• Marine biology
• Evolutionary biology
• Ecology

Background:

• Marine taxa often exhibit complex life cycles with distinct larval and adult stages.
• Larval stages are frequently more sensitive to environmental stress than adult stages.
• Understanding stage-specific adaptation is crucial for predicting species' responses to environmental change.

Purpose of the Study:

• To explore how complex life histories influence a population's capacity to adapt to environmental change.
• To investigate the impact of differential environmental stress sensitivity on the tempo of adaptive evolution.
• To identify key parameters affecting species' persistence under changing environmental conditions.

Main Methods:

• Utilized a heuristic model to simulate populations with complex life histories.
• Incorporated factors such as genetic correlations in stress tolerance, genetic variance per stage, and stage-specific plasticity.
• Analyzed the relationship between life history complexity and evolutionary potential.

Main Results:

• Increased life history complexity generally reduces evolutionary potential to cope with environmental change.
• Genetic correlations, variance levels, and plasticity interact to determine the maximum rate of environmental change a species can tolerate.
• Marine organisms with complex life cycles are predicted to be highly vulnerable to anthropogenic global change.

Conclusions:

• Complex life histories can limit the adaptive capacity of marine species facing environmental change.
• Differential sensitivity and genetic factors across life stages are critical for species' resilience.
• Empirical data on key parameters are needed to accurately assess the vulnerability of marine taxa to global change.