Stillhead
Posts: 2800
Joined: 12/19/2003 Status: offline
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There are many different kinds that have different life cycles. The cicadas with longer life cycles emerge in larger numbers, but there are a few around every year. I'm sure if you went outside right now in that area you'd probably hear them. The adults appear bigger than that because they are mostly all wings. http://en.wikipedia.org/wiki/Cicada [edit] Life cycle Time series photos of a Tibicen dog day cicada molting in Ohio, US.After mating, the female cuts slits into the bark of a twig, and into these she deposits her eggs. She may do so repeatedly, until she has laid several hundred eggs. When the eggs hatch, the newborn nymphs drop to the ground, where they burrow. Most cicadas go through a life cycle that lasts from two to five years. Some species have much longer life cycles, e.g. the Magicicada goes through a 17- or occasionally 13-year life cycle. These long life cycles are an adaptation to predators such as the cicada killer wasp and praying mantis, as a predator could not regularly fall into synchrony with the cicadas. Both 13 and 17 are prime numbers, so while a cicada with a 15-year life cycle could be preyed upon by a predator with a three- or five-year life cycle, the 13- and 17-year cycles allow them to stop the predators falling into step.[8] The insects spend most of the time that they are underground as nymphs at depths ranging from about 30 cm (1 ft) up to 2.5 m (about 8½ ft). The nymphs feed on root juice and have strong front legs for digging. In the final nymphal instar, they construct an exit tunnel to the surface and emerge. They then molt (shed their skins), on a nearby plant for the last time and emerge as adults. The abandoned skins remain, still clinging to the bark of trees.
< Message edited by Stillhead -- 8/4/2008 8:21:55 PM >
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