These centipedes ‘see’ sunlight, even without eyes

You wouldn’t want to step on a Chinese red-headed centipede. These venomous pencil-length arthropods scutter beneath the leaves of East Asian and Australian forests, their black, multisegmented bodies and bright red pincers hidden from view. They creep unseen in the darkness despite not being able to tell light from dark because they lack eyes entirely. Now, researchers have figured out how these centipedes avoid the sunlight they can’t see. When the rays heat their antennae, they spark a heat-related response that alerts the leggy arthropods to seek shelter, researchers report today in the Proceedings of the National Academy of Sciences . The antennae are packed with muscles and covered in sensitive hairlike projections that help the bugs make sense of their surroundings, says Paul Marek, an entomologist at the  Virginia Polytechnic Institute and State University who studies eyeless millipedes and was not involved in the new study. “They use them like a blind person's cane to essentially feel around in the dark.” Myriapods, a group that includes centipedes and millipedes, have gradually simplified their vision over evolutionary history. Several of these critters lack eyes entirely. In the perpetual darkness beneath the leaflitter, sight is less important than touch, which they use to pinpoint prey including worms, spiders, scorpions, and even small reptiles and mice. Their lack of vision doesn’t make the myriapods any le...
Source: ScienceNOW - Category: Science Source Type: news