The Biased Evolution of Generation Time.

Area of Science:

• Evolutionary Biology
• Life-History Theory
• Population Genetics

Background:

• Life-history traits significantly influence an organism's generation time.
• Semelparous and iteroparous reproductive strategies result in different generation times.
• Shorter generation times can be advantageous for population growth in stable, resource-rich environments.

Purpose of the Study:

• To investigate the neutral evolution of life-history strategies with varying generation times.
• To determine the evolutionary outcome of generation time when mutation is considered.
• To explore the influence of population size and selection on life-history evolution.

Main Methods:

• Theoretical modeling of neutral evolution.
• Analysis of life-history strategies under different environmental conditions (stable, limiting).
• Consideration of mutation rates and their impact on strategy replacement.

Main Results:

• When mutation is factored in, the slowest life-history strategy (longest generation time) emerges as the most probable evolutionary outcome.
• Longer generation times lead to fewer mutants per unit time, reducing the likelihood of strategy replacement.
• A 'turnover bias' favors the evolution of strategies with longer generation times.

Conclusions:

• Mutation introduces a bias favoring longer generation times, challenging the simple advantage of faster growth in stable environments.
• The evolutionary impact of this bias is contingent on population size and the specific nature of selection on life-history traits.
• Understanding the interrelationships between life-history traits is crucial for predicting evolutionary trajectories.