The wolves are exposed to cancer-causing radiation as they roam the wastelands of the abandoned city - with researchers finding part of their genetic information seems resilient to increased risk of the disease.
40 years seems like a relatively short time for natural evolutionary processes to adapt a mammal to a highly radioactive environment. That’s like 10 to 20 generations of wolf and suddenly they are cancer resistant?
After all the needless loss of life surrounding the Chernobyl reactor explosion, finding viable cancer-resistant genetic mutations would be the ultimate silver lining.
A mutation for having a higher radiation resistance or higher resistance to cancer is something that already happens in nature, but in most of the animal world those are relatively useless traits, normally cancer doesn't develop fast enough to stop procreation.
In Chernobyl, the highly elevated radiation would normally kill animals before they can even breed. The ones that don't have the resistance die before they get the chance, the ones that do have a higher resistance breed.
With humans in the modern age, a resistance to cancer or radiation trait never gets the chance to become a dominant evolutionary trait as most all people only develop the cancer later in life and the ones that do get cancer early more and more often can get treatment giving them a chance to procreate even when they got cancer young.
Outside Chernobyl, there is no evolutionary pressure for a trait like that to become dominant.
Living long enough to procreate is the primary drive in nature.
We generally don't see fast evolutionary changes in nature because nature doesn't change quickly often.
Leave it to us, humans, to create situations where the change is drastic and quick.
If you have an extremely high infant mortality rate, it won't take that long.
If the radiation kills off a high enough percentage of individuals without cancer resistance it won't take long at all.
Theoretically you could do it in only 2-3 generations if you had environmental factors that could give 100% of individuals without resistance cancer.
And that trait does exist in nature already, it's just rare and mostly useless until environmental pressures only allow those individuals to reproduce.
The thing is, the exclusion zone isn't uniformly radioactive. The hottest spots are not areas that wild life would normally spend a lot of time near.
Then there's the fact that the way we're all taught about radiation and cancer is just flat out wrong. The Linear No Threshold model that most people know was actually created by the Rockefeller Foundation in an attempt to slow the adoption of nuclear power.
Combine those two factors, and you get stories like this, where researchers are shocked that higher than average radiation exposure doesn't equate to a simple linear increase in cancer rate.
Not that these wolves haven't developed an increased resistance to radiation. But it's not a new thing. Every living creature on this planet has mechanisms to repair DNA from radiation exposure. These wolves are simply better at it now than generations past.