What happens when the lights are left on? Transcriptomic and phenotypic habituation to light pollution

Area of Science:

• Environmental Science
• Animal Behavior
• Ecology

Background:

• Artificial light at night (ALAN) is a widespread environmental pollutant.
• ALAN exposure can cause immediate behavioral and physiological changes in animals.
• Organisms may possess habituation mechanisms to cope with chronic light pollution.

Purpose of the Study:

• To investigate habituation to dim artificial light at night (ALAN) in zebra finches (Taeniopygia guttata).
• To assess behavioral, physiological, and gene expression responses to chronic and re-exposure to ALAN.
• To understand the capacity of birds to persist in light-polluted environments.

Main Methods:

• A 6-month repeated measures design was used to expose zebra finches to dim ALAN (0.3 lux).
• Behavioral observations, oxidative stress markers, telomere attrition, and blood transcriptome analysis were conducted.
• Responses to initial exposure, chronic exposure, and re-exposure were measured.

Main Results:

• Zebra finches demonstrated tolerance to chronic ALAN exposure.
• Persistent behavioral responses were observed for up to 8 weeks post-exposure.
• Oxidative stress levels decreased under chronic ALAN, while the transcriptome showed distinct responses to past and re-exposure.

Conclusions:

• Organisms can exhibit resilience to chronic environmental stressors like ALAN.
• Habituation to ALAN may involve complex physiological and behavioral adjustments.
• Birds possess mechanisms to cope with increasing light pollution, though long-term impacts require further study.