Chernobyl's Dogs Are Evolving. Researchers Are Not Sure Why

Dogs living near the Chernobyl nuclear power plant show genetic patterns consistent with natural selection, according to a study published in Genes.

However, researchers cannot determine what drives the differences or whether they offer a survival advantage.

The findings strengthen the hypothesis that natural selection helped distinguish the plant’s free-roaming dogs from other canine populations.

They do not establish that radiation caused the changes or that the animals have evolved specific protection against it.

Radiation is one possible influence.

The study could not separate its effects from those of other pollutants or the circumstances that shaped the dogs’ history, according to WIRED Español.

Genetic Clues

Scientists already knew that dogs near the plant had a markedly different genetic profile from other populations.

The research examined whether natural selection could have contributed to that divide.

Researchers compared DNA from dogs living near the plant with that of dogs in Chernobyl city, about 16 kilometers away.

They also examined other canine populations to assess whether isolation could explain the differences.

The analysis indicated that chance alone could not explain the patterns.

Some DNA regions in the plant’s dogs showed signals consistent with natural selection, a process in which traits that help animals survive and reproduce can pass to subsequent generations.

Near those regions, researchers identified genes associated with DNA repair, immune responses, and cell survival.

These functions could be relevant to coping with environmental stress, making them clues to possible adaptation.

However, identifying those genetic associations does not establish which environmental pressures favored the variants or what practical benefit, if any, they provide.

Dogs in an Abandoned Landscape

The animals include descendants of pets left behind when residents evacuated after the 1986 nuclear accident in what was then the Soviet Union.

Many settlements in present-day Ukraine were abandoned, while dogs and wildlife continued living in the region.

The exclusion zone has also become a refuge for wolves, deer, wild boar and lynx.

Studies have found abundant populations of large mammals, which researchers largely link to reduced human activity, including hunting and landscape changes.

That wider recovery provides context for the animals’ continued presence, while the genetic findings leave unresolved which conditions have shaped the dogs near the plant.