Study finds rapid evolution in dogs living near Chernobyl power plant.


According to a new study, the feral dogs living in and around the Chernobyl Nuclear Power Plant are experiencing rapid evolution due to increased levels of radiation. For decades, scientists have been studying the effects of radiation on animals living in or near the power plant, including their health, growth, and evolution. The new study analyzed the DNA of 302 feral dogs living near the power plant and compared them to dogs living 10 miles away. The study found remarkable genetic differences between the two groups of dogs, suggesting that radiation exposure may be altering their genomes and potentially speeding up evolution.

However, the study doesn't prove that radiation is the sole cause of these genetic differences. Rather, it provides an essential first step in understanding how these irradiated populations compare to dogs living elsewhere. While the Chernobyl Nuclear Reactor explosion happened nearly four decades ago, the power plant and many parts of the surrounding area remain uninhabited by humans, and animals of all kinds have thrived in humanity’s absence. Thousands of feral dogs, in particular, have been living in the area, many of which are descendants of pets left behind during the evacuation.

The Chernobyl Exclusion Zone (CEZ), where the power plant is located, covers an area about the size of Yosemite National Park. Biologists are now investigating how decades of radiation exposure may have altered the animals' genomes and whether it has also affected natural evolution. Scientists from the University of South Carolina and the National Human Genome Research Institute have started examining the DNA of feral dogs in and around the CEZ to understand how radiation exposure may have altered their genomes.

One of the study's co-authors, Elaine Ostrander, a dog genomics expert at the National Human Genome Research Institute, told The New York Times, “Do they have mutations that they’ve acquired that allow them to live and breed successfully in this region? What challenges do they face, and how have they coped genetically?” While radiation-induced mutations are not a new idea, scientists have been analyzing certain animals living in the CEZ for years, including bacteria, rodents, and birds.

One study conducted in 2016 found that Eastern tree frogs, which are usually green, were more commonly black within the CEZ, suggesting that the frogs experienced a beneficial mutation in melanin that helped ionize the surrounding radiation. The scientists wondered whether a similar phenomenon was happening to the wild dogs of Chernobyl. The new study found that the feral dogs living near the power plant had distinct genetic differences from dogs living in nearby Chernobyl City.

While the study may suggest that radiation exposure is causing rapid evolution in the dogs, it is only the first step in proving that hypothesis. One environmental scientist who spoke with Science News said that these studies can be difficult to conduct due to the challenges of sussing out radiation-induced mutations from other effects like inbreeding. Despite the lack of firm conclusions, the study provides a template for further investigation into the effects of radiation on larger mammals. The DNA of dogs living in non-irradiated areas can be compared to those in and around the Chernobyl Power Plant and Chernobyl City, which could yield important information about the long-term effects of radiation exposure on animals.

The Chernobyl disaster, which occurred on April 26, 1986, remains one of the world's greatest nuclear disasters. While the area around the power plant was once a wasteland, it has become an unparalleled scientific opportunity to understand radiation and its impact on natural evolution. The study of the feral dogs living in the CEZ is just one example of how scientists are continuing to learn about the long-term effects of radiation exposure on the environment and its inhabitants.