Evolutionary tracking is determined by differential selection on demographic rates and density dependence

Area of Science:

• Ecology
• Evolutionary Biology
• Population Dynamics

Background:

• Current ecological forecasts predict high extinction rates by 2050, often neglecting evolutionary adaptation.
• Traditional models oversimplify population dynamics by focusing on the intrinsic growth rate (r) rather than specific demographic rates (birth and death).
• Environmental changes can impose differential selective pressures on birth and death rates, impacting population density dependence.

Purpose of the Study:

• To investigate how genetic adaptation and density-dependent selection influence species' persistence under environmental change.
• To develop more accurate forecasting models that incorporate demographic mechanisms and evolutionary potential.
• To understand the differential impact of environmental change on birth versus death rates.

Main Methods:

• Utilized a continuous-time Markov chain model to simulate population growth.
• Incorporated trait evolution via mutations during birth events.
• Analyzed the stochastic dynamics of the logistic growth model under environmental change.

Main Results:

• Persistence through evolutionary tracking is more likely when environmental change primarily affects birth rates.
• Species evolving responses to density-dependent changes are less vulnerable to extinction.
• Models incorporating demography and selection on density dependence provide better extinction predictions.

Conclusions:

• Accurate forecasting of species' responses to climate change requires integrating demographic factors and adaptive evolution.
• Evolutionary adaptation, particularly in response to changes in birth rates and density dependence, is crucial for species persistence.
• Future ecological models must account for these biological mechanisms to reliably predict extinction risk.