A fake head might sound like a magician’s prop, but for some butterflies it’s a lifesaving illusion. Many species—including the Bartram’s scrub-hairstreak, which lives exclusively in Florida’s pine rocklands, one of the world’s most critically endangered habitats—display markings on the back of their hind wings that resemble a face. A bright patch of color, faux “antennae,” an eyespot, head-shaped contours, and convergent lines combine to look like a creature staring upward. The system works to misdirect attacking predators. “Butterflies may suffer some wing tear but are able to continue to live, fly, and reproduce,” says researcher Tarunkishwor Yumnam. With a colleague at the Indian Institute of Science Education and Research Thiruvananthapuram, Yumnam recently studied more than 900 butterfly species and found that four of those five false features evolved together, which suggests that a common pressure drove their evolution. It’s possible the butterflies also enhance the effect with a little acting: Yumnam hypothesizes that the butterflies’ hind wing rubbing might mimic flicking antennae, thus amplifying the ruse. Survival, as ever, involves using one’s head.
The National Geographic Society funds Explorer Joel Sartore’s Photo Ark project, which aims to document every species living in the world’s zoos, aquariums, and wildlife sanctuaries.
