Insert Mothra joke here. From Mother Jones: Fukushima Radiation Gives Rise to Mutant Butterflies?
Researchers collected butterflies immediately following the nuclear meltdown and six months later, both from the surrounding areas of Fukushima and from various other localities in Japan where the butterfly is common. As compared with the butterflies collected from elsewhere in the country, Fukushima butterflies showed some abnormally-developed legs, dented eyes, deformed wing shapes, and changes to the color and spot patterns of their wings, with an overall abnormality rate of around 12 percent.