A few months after the devastating Japanese tsunami of March 2011, researchers started examining butterflies near the Fukushima Daiichi nuclear plant. In the first batch of 100 studied, 12% exhibited mutations. As those butterflies then mated, the mutation rate skyrocketed to 34%, demonstrating that the deformed genes were passing down to offspring. A few months later, the researchers analyzed 200 more young butterflies and, in a report released in August, divulged that more than 50% now carried some form of mutation. While any radiation-based mutation is cause for concern, experts say humans are unlikely to experience similar effects. “Humans are totally different from butterflies and they should be far more resistant” to radiation, said Joji Otaki, an associate professor at the University of the Ryukyus in Okinawa.
