Change in prey genotype frequency rescues predator from extinction

Area of Science:

• Ecology
• Evolutionary Biology
• Theoretical Biology

Background:

• Indirect evolutionary rescue (IER) describes how one species' evolution can prevent another's extinction in a shared environment.
• Previous models suggested IER in predator-prey systems, where prey evolution rescues predators from extinction.
• The influence of environmental stressors like increased mortality and initial species frequencies on IER remains underexplored.

Purpose of the Study:

• To investigate how increased predator mortality and initial prey frequencies impact indirect evolutionary rescue.
• To determine the conditions under which prey evolution can facilitate predator survival in a changing environment.

Main Methods:

• Conducted model simulations of predator-prey dynamics.
• Performed experimental studies using rotifers feeding on algae.
• Analyzed the effects of varying predator mortality rates and initial prey type frequencies.

Main Results:

• Demonstrated indirect evolutionary rescue in predator-prey systems under increased predator mortality.
• Found that IER is contingent upon the prey's capacity for evolution and the initial frequency of defended prey.
• Observed that high initial frequencies of defended prey can lead to predator extinction, even with prey evolution, due to delayed shifts in prey composition.

Conclusions:

• Indirect evolutionary rescue is a frequency-dependent process influenced by predator mortality and prey evolution.
• Conservation strategies must consider the initial community structure and evolutionary potential to predict and manage species persistence.
• Understanding these dynamics is crucial for predicting ecological community responses to environmental change.