"According to the report, mutations caused by Fukushima radiation had affected 12% of adult pale grass blue butterflies in the surrounding area two months after the March 2011 disaster. When they mated, these butterflies produced an offspring with an 18% mutation rate. In the next generation, mutations were found in 34% of the insects born. When scientists returns to Fukushima in September 2011, the adult butterflies they collected displayed a 28% mutation rate and their offspring had a whopping 58% mutation rate." - Iván Abrego from Bookmarklet