Ionizing radiation and melanism in Chornobyl tree frogs
Pablo Burraco1,2,3, Germán Orizaola1,4,5
1Animal Ecology, Department of Ecology and Genetics, Evolutionary Biology Centre Uppsala University Uppsala Sweden.
Evolutionary Applications
|October 3, 2022
Summary
Eastern tree frogs exposed to Chornobyl radiation developed darker skin coloration. This adaptation, linked to the 1986 accident, appears protective and without physiological cost to the frogs.
Area of Science:
- Ecology
- Evolutionary Biology
- Environmental Science
Background:
- Human activities are altering global ecosystems, with ionizing radiation as a significant pollutant.
- The 1986 Chornobyl accident released substantial radioactive material, impacting surrounding environments.
Purpose of the Study:
- To investigate the influence of Chornobyl radiation exposure on the dorsal skin coloration of Eastern tree frogs (Hyla orientalis).
- To assess the relationship between frog skin color, radiation levels, and oxidative stress.
Main Methods:
- Sampling of Eastern tree frogs across a contamination gradient in northern Ukraine.
- Assessment of dorsal skin coloration, radiation exposure levels (historical and current), and oxidative stress markers.
Main Results:
- Frog skin coloration was darker in areas with higher radiation levels at the time of the Chornobyl accident.
- Frogs within the Chornobyl Exclusion Zone exhibited significantly darker dorsal skin coloration compared to those outside.
- Darker coloration was not associated with negative impacts on body condition or oxidative status.
Conclusions:
- The study suggests that historical exposure to high ionizing radiation from the Chornobyl accident may have selected for darker skin coloration in Eastern tree frogs.
- Melanin pigmentation is proposed as a protective mechanism against ionizing radiation, potentially buffering against free radicals and DNA damage.
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