Butterflies collected from in and around the Fukushima nuclear disaster area suffer from mutations that indicate lasting ecological effects from the radioactive fallout. The butterflies are showing abnormalities in their legs, antennae, and abdomens, and have dents in their eyes, according to a study published in Scientific Reports. Scientists collected the butterflies two months after the disaster and found that 12 percent of the samples suffered from abnormalities, with the rate of mutation increasing each generation. In a follow-up collection last September, scientists noted that the rate of mutation rose to 28 percent, and the number of mutated offspring increased to 52 percent of the sample. "Our results are consistent with the previous field studies that showed that butterfly populations are highly sensitive to artificial radionuclide contamination in Chernobyl and Fukushima," the study said. "Together, the present study indicates that the pale grass blue butterfly is probably one of the best indicator species for radionuclide contamination in Japan.” Because sensitivity to irradiation varies between species, there shouldn’t be concerns about these type of mutations in humans.