In a recent study published in Scientific Reports, researchers found that the pale grass blue butterflies that are commonly found around Fukushima have been affected by the radiation released from the nearby nuclear power plant.
Usually a subdued, gray-blue color with touches of purple, the butterfly was already under investigation by the researchers, who wanted to see if it could be used to help study the effects of global warming. After the disaster at the plant, however, they found that some of the butterflies had strangely shaped antennae, crumpled wings, and other deformities.
Curious about these changes, the researchers collected butterflies from 10 different sites around the plant and bred them in the lab. What they found was disturbing: The offspring of the original butterflies showed even more mutations. When the scientists again collected adults from the sites six months later, they found that the butterflies showed a mutation rate that was more than double that of those found earlier after the accident.
Those familiar with the meltdown at Ukraine’s Chernobyl plant know that mutating insects aren’t an uncommon occurrence after a nuclear accident. For example, science illustrator Cornelia Hesse-Honegger recorded the mutations of several species of insects around Chernobyl when she visited the area in 1987, showing that the insects had developed everything from missing limbs to stunted wings to misshapen antennae.
In the case of the Fukushima butterflies, researchers concluded that the mutations were from contaminated food that the butterflies ate in addition to the genetic material passed down from their parents.
The study, which demonstrates that insects can be used as significant environmental indicators, “is important and overwhelming in its implications for both the human and biological communities living in Fukushima,” said Tim Mousseau, a University of South Carolina biologist, in an interview with BBC News. In addition, the butterfly shows that the Fukushima disaster could have far-reaching impacts for the animals exposed to radiation.
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