Rare butterfly thrives on, and because of, US military bases [http://cmsenvis.cmsindia.org/resources/newspaper/details.asp?id=91664]In the shadow of giant war machines, a tiny rare butterfly is flourishing. Oddly, experts say, the U.S. military gets the credit.The frosted elfin, which flutters along on a 1—inch (2.5 centimeters) wingspan, has found a home at several defense installations because of the way the military manages open spaces, said Robyn Niver, an endangered species biologist with the U.S. Fish and Wildlife Service.