News Animals How luna moths grow extravagant wings Warm temperatures, not just predator pressure, may favor long, bat-fooling streamers Long, skinny streamers on the hind wings of luna moths tend to evolve in certain climate conditions, a new study shows. Keith Ramos/USFWS By Susan Milius 17 hours ago For the first time, biologists have linked the ribbony “tails” streaming from big, green luna moths’ hind wings with, of all things, a cozy climate. Those dangling wing tails rank among such evolution-was-drunk novelties as the narwhal’s single unicorn tusk or the peacock’s giant feather train. Wing streamers with twisting or cupped ends have evolved independently at least five times in the family of luna and other moon moths (Saturniidae), says behavioral ecologist Juliette Rubin, now at the Smithsonian Tropical Research Institute in Balboa, Panama. Her new data crunch of environmental factors links the ribbony tails with growing up in a long stretch of even temperatures, she and colleagues report May 7 in Proceedings of the Royal Society B. Sign up for our newsletter We summarize the week's scientific breakthroughs every Thursday.