The local Chernobyl frogs have turned from green to black. 36 years after the Chernobyl nuclear accident, the exclusion zone has made the characteristic tree frogs, from an intense and bright green color, now look completely dark.
It was one of the worst nuclear disasters in history.
This location in northern Ukraine, then under Soviet rule, witnessed the largest release of radioactive material into the environment in human history. The accident caused huge amounts of radioactive caesium-137 to be deposited in most of Ukraine, and even in parts of Norway and the United Kingdom. The consequences, we are still seeing almost four decades later.
Now the exclusion zone, which covers 2,600 square kilometers , has become a huge nature reserve that is home to a multitude of species. Scientists have used this site to investigate how animals might adapt to these extremely high levels of radiation in their environment. One of the most striking discoveries has been the transformation of the local tree frogs: they have gone from being mostly bright green to black.
black color to survive
According to the experts, who publish their findings in the journal Evolutionary Applications , the darker frogs had a better chance of surviving when the disaster struck in 1986, making them more numerous today. Thus, in an evolutionary effort for survival, this dark coloration may not be the result of genetic mutations caused by radiation contamination, but may be due to frogs that had darker skin coloration at the time of the accident, which They are normally a minority within their populations, surviving longer due to the protective effects of melanin.
More than ten generations of frogs have lived and died since the accident, suggesting that a very rapid process of natural selection may explain why the predominant frogs are now black (because radiation kills bright green ones). ).
And what does the color black do to make them more resilient?
The pigment that darkens animal skin, melanin, works to reduce cell damage caused by radiation. (This means that people with darker skin will be less likely to experience cell damage after radiation exposure, for example.
One more proof of the recovery of ecosystems from disasters as imposing as this one.
Referencia: Ionizing radiation and melanism in Chornobyl tree frogs
Pablo Burraco, Germán Orizaola
First published: 29 August 2022 Evolutionary Applications
https://doi.org/10.1111/eva.13476
