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Ballooning, sometimes called kiting, is a behaviour in which spiders and some other invertebrates use air-borne dispersal to move between locations.〔Heinrichs, Ann R. (2004) "(Spiders )". Compass Point Books, ''Primary School : Nature's Friends'' series; Minneapolis, Minn. ISBN 9780756505905. She observes that the so called ballooning is like a kite〕〔http://web.archive.org/web/20110719210153/http://fms.holycross.edu/JoA_free/JoA_v3_n3/JoA_v3_p185.pdf〕 ==Description== A spider (usually limited to individuals of a small species), or spiderling after hatching,〔Bond, J.E. "(Systamatic and Evolution of the Californian trapdoor spider genus ''Aptostichus'' Simon (Araneae: Mygalomorphae: Euctenizidae) )". ''Virginia Polytechnic Institute and State University.'' 1999. Accessed 2009-07-18.〕 will climb as high as it can, stand on raised legs with its abdomen pointed upwards ("tiptoeing"), and then release several silk threads from its spinnerets into the air. These automatically form a triangular shaped parachute〔 which carries the spider away on updrafts of winds where even the slightest of breezes will disperse the arachnid.〔〔 The Earth's static electric field may also provide lift in windless conditions. Many spiders use especially fine silk, called "gossamer"〔Oxford English Dictionary 2nd ed.: Gossamer, noun and adjective: fine filmy substance, consisting of cobwebs, spun by small spiders, which is seen floating in the air in calm weather, esp. in autumn, or spread over a grassy surface: occas. with a and pl., a thread or web of gossamer.〕 to lift themselves off a surface, and silk also may be used by a windblown spider to anchor itself to stop its journey. The term "gossamer" is used metaphorically for any exceedingly fine thread or fabric. Biologists also apply the term "balloon silk" to the threads that mechanically lift and drag systems. It is generally thought that most spiders heavier than 1 mg are unlikely to use ballooning. Because many individuals die during ballooning, it is less likely that adults will balloon compared to spiderlings. However, adult females of several social ''Stegodyphus'' species (''S. dumicola'' and ''S. mimosarum'') weighing more than 100 mg and with a body size of up to have been observed ballooning using rising thermals on hot days without wind. These spiders use tens to hundreds of silk strands, which form a triangular sheet with a length and width of about 〔 In Australia, in 2012 and in May 2015, millions of spiders were reported to have ballooned into the air, and landing, making the ground seem like snow covered the ground with the white spiderwebs. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Ballooning (spider)」の詳細全文を読む スポンサード リンク
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