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	• Science Desk >> ATW -------------------------------------------------------------------------------- Cicadas (George) “Today I’m going to tell you all about an amazing insect you’ve probably never heard of, the Cicada.” “So what’s so amazing about these winged grasshopper-like insects? Well first of all they’re always on time! And what I mean by that is Cicadas only show themselves once every 17 years. They spend most of their life underground sucking on roots and tree shrubs. At some point in the late spring, every 17 years, when the soil has warmed to 64 degrees Fahrenheit the Cicadas emerge from the ground by the millions all over the Eastern United States! If you live in this part of the US I’m sure you know what I’m talking about because right now Cicadas are turning up every where! Cicadas are unique for two main reasons. The first is that they use environmental cues such as the temperature of the soil to signal the end of their ground cycle. The second reason is that they are born with a certain genetic programming possibly timed to the flowering cycles of trees they feed off of, which gives them an internal biological clock telling them when it’s time to return to the surface! When they finally arrive every member of the population emerges from a hole, climbs a tree and sheds its skin for the last time. The brown, wrinkled nymph which has been living underground for so many years quickly becomes a one and a half-inch adult with a black body, orange wings and amazing red eyes. Once the male Cicadas get to a tree branch they produce a buzzing noise by vibrating two drum like organs on their bellies at great frequencies, this sound is a mating call that attracts the female Cicadas. Once mating is completed the female lays up to 600 tiny eggs which after 6 weeks hatch and the rice sized nymphs fall to the ground, bury themselves in the soil and will not be seen until seventeen years later! In two to four weeks the Cicadas that are not eaten by raccoons, foxes or birds will naturally die off littering the ground and fertilizing the soil. Now if you want to learn more about Cicadas check out the ATW website at ATW ONLINE DOT ORG. That's it from the Science Desk. More Information 1. Cicada mania is "dedicated to cicadas, the most amazing insects in the world." http://www.cicadamania.org/ 2. Frequently asked questions about Cicadas http://www.cicadamania.org/faq.html 3. Cicadas Are Right on Time…But Why? http://www.genomenewsnetwork.org/articles/2004/05/11/cicada.php 4. Check out what National Geographic has to say about the Cicada Invasion http://news.nationalgeographic.com/news/2004/05/0511_040511_cicadas2.html 5. Listen to the chorus calls of different kinds of Cicadas and would you believe that some humans find these critters to be a delicious meal! Find out more on National Public Radios website. http://www.npr.org/features/feature.php?wfId=1866011 6. Low-Fat, High-Protein Cicadas: New Health Snack? http://news.nationalgeographic.com/news/2004/05/0503_040503_cicadafeast.html 7.Check out 'Periodical Cicadas' for some great pictures and information about Cicadas http://biology.clc.uc.edu/steincarter/cicadas.htm © 2004 WXXI-TV/ Assignment: The World. All Rights Reserved.