Frogs adapt to physiologically costly anthropogenic noise

Area of Science:

• Ecology
• Environmental Science
• Amphibian Biology

Background:

• Amphibian populations are declining globally due to human activities.
• Anthropogenic noise is a significant environmental stressor impacting ecological processes.
• The capacity of populations to adapt to novel stressors like noise is largely unknown.

Purpose of the Study:

• To investigate adaptation to traffic noise in wood frog (Rana sylvatica) populations.
• To determine if populations with historical exposure to traffic noise exhibit different physiological responses to noise compared to naive populations.

Main Methods:

• Wood frog eggs were collected from sites with varying traffic noise levels.
• Hatchlings were reared under controlled conditions and exposed to noise.
• Sublethal, fitness-relevant effects of noise on immune and stress responses were measured.

Main Results:

• Noise exposure impaired the production of antimicrobial peptides, crucial for disease defense.
• Noise altered leucocyte production and increased corticosterone levels in frogs from quiet origins.
• Frogs from noise-legacy populations showed no significant negative impacts on immune and stress responses when exposed to noise.

Conclusions:

• Wood frog populations with a history of traffic noise exposure appear to have adapted to this anthropogenic stressor.
• Adaptation to noise can mitigate fitness-relevant physiological costs associated with traffic noise.
• Anthropogenic noise can drive adaptation in novel environments, altering population dynamics and resilience.