Chernobyl dogs’ survival tricks
More than 35 years after the world’s worst nuclear accident, the dogs of Chernobyl roam among decaying, abandoned buildings in and around the closed plant – somehow still able to find food, breed and survive.
Scientists hope that studying the dogs can teach humans new tricks about how to live in the harshest, most degraded environments.
They published the first of what they hope will be many genetics studies in the journal Science Advances yesterday, focusing on 302 free-roaming dogs living in an officially designated ‘‘exclusion zone’’ around the disaster site.
The scientists have identified populations whose differing levels of radiation exposure may have made them genetically distinct from one another and from other dogs worldwide.
‘‘We’ve had this golden opportunity’’ to lay the groundwork for answering a crucial question: ‘‘How do you survive in a hostile environment like this for 15 generations?’’ says geneticist Elaine Ostrander of the National Human Genome Research Institute, one of the study’s many authors.
Fellow author Tim Mousseau, professor of biological sciences at the University of South Carolina, says the dogs ‘‘provide an incredible tool to look at the impacts of this kind of a setting’’ on mammals overall.
Chernobyl’s environment is singularly brutal. On April 26, 1986, an explosion and fire at the Ukraine power plant caused radioactive fallout to spew into the atmosphere.
Thirty workers were killed in the immediate aftermath, while the longterm death toll from radiation poisoning is estimated to eventually number in the thousands.
The researchers say most of the dogs they are studying appear to be the descendants of pets that residents were forced to leave behind when they evacuated the area.
Mousseau has been working in the Chernobyl region since the late 1990s, and began collecting blood from the dogs around 2017. Some of the dogs live in the plant, while others are about 15km or 45km away.
At first, Ostrander says, the scientists thought that the dogs might have intermingled so much over time that they’d be much the same. But through DNA, they could readily identify dogs living in areas of high, low and medium levels of radiation exposure.
‘‘That was a huge milestone for us. And what’s surprising is we can even identify families’’ – about 15 different ones.
Now researchers can begin to look for alterations in the DNA.
‘‘We can compare them and we can say, ‘OK, what’s different, what’s changed, what’s mutated, what’s evolved, what helps you, what hurts you at the DNA level?’,’’ Ostrander says.
This will involve separating nonconsequential DNA changes from purposeful ones.
Scientists say the research could have wide applications, providing insights about how animals and humans can live now and in the future in regions of the world that are under ‘‘continuous environmental assault’’ – and in the highradiation environment of space.
Researchers have already started on the follow-up research, which will mean more time with the dogs at the site about 100km from Kyiv.
Mousseau says the team has grown close to some dogs, naming one Prancer because she excitedly prances around when she sees people.
‘‘Even though they’re wild, they still very much enjoy human interaction. Especially when there’s food involved.’’