Climate change and evolution: disentangling environmental and genetic responses.

Area of Science:

• Ecology
• Evolutionary Biology
• Climate Change Science

Background:

• Rapid climate change exerts selection pressures on fitness traits.
• Microevolutionary adaptation is a potential mechanism to mitigate climate change impacts.

Purpose of the Study:

• To review empirical evidence for recent microevolutionary responses to climate change.
• To assess the quality of evidence and distinguish genetic from phenotypic responses.
• To explore difficulties in detecting microevolutionary responses to natural selection.

Main Methods:

• Literature review of longitudinal studies on microevolution and climate change.
• Analysis of quantitative genetic studies in long-term vertebrate studies.
• Emphasis on distinguishing genetic (evolutionary) from phenotypic (plastic) responses.

Main Results:

• Signatures of climate change are evident in ecological processes, but microevolutionary examples are rare.
• Evidence for microevolution is often based on nongenetic (plastic) data.
• Many observed adaptations to environmental change may be environmentally induced plastic responses rather than genetic adaptations.

Conclusions:

• Clear-cut evidence for significant evolutionary adaptation to ongoing climate warming is scarce.
• Distinguishing plasticity from genetic adaptation is crucial for understanding climate change responses.
• Further research is needed to robustly demonstrate microevolutionary adaptation to climate change.