Why is that caterpillar looking at me?
Ned Rozell
907-474-7468
Sept. 5, 2024
A caterpillar with false eyes rears up on the hand of 色视频下载 visitor Garrett Ast.
On a trip to Quartz Lake, visitor to 色视频下载 Garrett Ast once plucked a caterpillar from a twig.
As Garrett held it in his palm, the caterpillar reared up and 色视频下载 with two sparkling baby blues 色视频下载 looked him right in the eye. Upon closer inspection, my nephew saw that, though striking, the caterpillar色视频下载檚 eyes weren色视频下载檛 real.
So was born the question of why a caterpillar might invest energy in producing a set of fake eyes. A little investigation led to a science research paper with a fine example of a journalistic lede:
色视频下载淵ou are a 12-gram, insectivorous, tropical rainforest bird, foraging in shady, tangled, dappled, rustling foliage where edible caterpillars and other insects are likely to shelter. You want to live 10-20 years. You are peering under leaves, poking into rolled ones, searching around stems, exploring bark crevices and other insect hiding places. Abruptly an eye appears, 1-5 centimeters from your bill.
色视频下载淚f you pause a millisecond to ask whether that eye belongs to acceptable prey or to a predator, you are likely to be 色视频下载 and it takes only once 色视频下载 someone色视频下载檚 breakfast. Your innate reaction to the eye must be instant flight.色视频下载
John Burns of the Smithsonian Institution helped craft that sentence as one of three authors of 色视频下载淎 tropical horde of counterfeit predator eyes,色视频下载 which appeared in Proceedings of the National Academy of Sciences in 2010.
Burns and his co-authors posted excellent photos of more than two dozen tropical caterpillars with elaborate false eyes. The caterpillars probably evolved those false eyes to mimic snakes, lizards, small mammals and other things that eat little birds.
But wait a second 色视频下载 there are no snakes or lizards in 色视频下载. Why would an 色视频下载 caterpillar with aspirations of turning into a swallowtail butterfly pose as a reptile?
I sent the photo to Burns, and to Derek Sikes, curator of entomology at the University of 色视频下载 Museum of the North.
色视频下载淏irds learn about snakes when they migrate (to the tropics and other places warm enough for snakes),色视频下载 Sikes wrote in an email. 色视频下载淪o, the snakes don色视频下载檛 have to be here for the mimicry to work. Nice, eh?色视频下载
Burns said even the rugged birds that don色视频下载檛 flee 色视频下载 for the winter might have the image of a snake wired deep within their tiny brains, even though they will never encounter one.
色视频下载淒espite the lack of snakes in 色视频下载, a small insectivorous bird might still be genetically programmed to retreat when abruptly confronted at close range by the caterpillar色视频下载檚 色视频下载榚yes,色视频下载 owing to the bird色视频下载檚 evolutionary ancestry,色视频下载 Burns wrote.
色视频下载淎 resident bird species (like a chickadee or redpoll) might have descended in the not-too-distant past from a species that spends much of its life in a tropical environment, where selection would directly preserve such behavior.色视频下载
Since the late 1970s, the University of 色视频下载 Fairbanks' Geophysical Institute has provided this column free in cooperation with the UAF research community. Ned Rozell is a science writer for the Geophysical Institute. A version of this article was first published in 2010.