The article was updated after initial publication. Grazie a Riccardo e Fljll per le segnalazioni. Alcuni sostenitori della teoria delle "scie chimiche" affermano che i "capelli d'angelo", i filamenti che in alcuni periodi dell'anno cadono abbondanti nei campi e nelle città, sono prodotti dalle scie stesse.
Quando si fa notare loro che l'origine più plausibile dei "capelli d'angelo" è la migrazione dei ragni che si spostano secernendo un filamento che fa da vela e li porta in quota grazie al vento e alle correnti ascensionali, arrivando ad altitudini notevolissime, i sostenitori della teoria delle "scie chimiche" spesso negano addirittura l'esistenza di questi aracnidi.
Ecco, per esempio, alcune statements of George Pattera:
Spiders migration do not exist ... certainly not at 5000 meters ... 7000 ... what it is.
(Pattera statement during a meeting of pro-chemtrail in Milan, April 19, 2009; video on Youtube )
They are certainly not the production (which would result in the industry, among other things, to cover the territorial Vercelli-Milano/Bologna-Ferrara!) glands serigene so-called "spiders high altitude," whose existence (in terms of entomological) we leave the preserve of urban legends, pace of CICAP .
( "silicon cotton? Not really!" , George Pattera; published on Scribd )
Let's see what the experts say instead of entomology and the scientific literature about these creatures that would "urban legends" .
John Jackman, entomologist at Texas A & M University
... after the birth, a certain type of young migratory spiders secrete long strands of silk, lifted by the wind, carrying the animal away, even for many kilometers. "It is easier to see the strings on a sunny day which follows a storm, "says Jackman." is a very common phenomenon. When the light is right if they can see hundreds of thousands to fly to heaven. "
( Science & Paranormal No. 40, November-December 2001)
Encyclopaedia Britannica, print edition, Vol 21 spider
Dispersal of spiderlings May be accomplished by different methods. in Some species, spiderlings Simply run away in all directions. But in the Majority of aerial dispersal species Takes place. This so-called ballooning coincides in with temperate zones of the sunny days of spring or autumn, if the eggs through quiescent Remain the winter. Each spiderling climbs to the end of a blade of grass, a twig, a pole or any protruding object, raises its abdomen and spins a thin thread of silk. As this gossamer thread is caught in the breeze, the spiderling lets go of the support on which it sat, climbs to the middle of the thread and is carried by air currents to a considerable height upward and to great distances horizontally. Gossamer threads have been encountered by airplanes five miles above sea level and one observer reported that he saw spider threads in the stratosphere. Spiderlings have also been caught in the rigging of ships several hundred miles from shore.
Encyclopaedia Britannica , edizione online, 2009, "spider"
Small spiders and the young of many larger species secrete long silk strands that catch the wind and can carry the spiders great distances. This behaviour, called ballooning, occurs in many families and expedites distribution. Some species are distributed in this way around the globe within the bounds of the northern jet stream. Ballooning spiders drift through the air at heights that range from 3 metres (10 feet) or less to more than 800 metres (2,600 feet).
( fonte )
Journal of the Kansas Entomological Society , 1975
Glick (1939), who collected airborne spiders up to 15,000 feet above the ground...
( Factors Influencing The Aerial Dispersal of Spiders (Arachnida: Araneida) , K.V. Yeargan, Department of Entomology, University of Kentucky, in Journal of the Kansas Entomological Society , Vol. 48, no. 3, July 1975)
Winter-Sleeping Wildlife , 1958
To reach new locations the spider travels by a means of transportation known as "ballooning". A spiderling or spider throws out streams of silk. These threads form a sort of "flying carpet." It rises on warm currents of ascending air, and spiders and spiderlings are borne aloft and scattered far and wide. Sometimes they go as high as 14,000 to 15,000 feet and travel hundreds or even thousands of miles.
(Will Barker, New York: Harper and Row, Pubs., 1958, pp. 94-96)
Microscopy UK , 1998
Ballooning allows many kinds of spiders to disperse around the world, wafted on air currents across even the widest oceans and highest mountains. When conditions of breeze and season are right, young spiders ascend to the top of any available elevation, spin a few short strands of silk, feel the tug of the wind, and let go. They arrived on Krakatau in 1883 within weeks after that volcanic island exploded and destroyed all life. Charles Darwin gathered them in mid-Atlantic during his trip on H.M.S. Beagle, and ballooning spiderlings have been collected from airplanes at very high altitude. I watched minute airborne spiders arrive on mid-Pacific islands from the nearest continent over two thousand miles away. I remember an astonishing spring day in the Eastern United States when from horizon to horizon the cloudless blue sky sparkled with pinpricks of light. It was so eerie, so beautiful, my skin rose in goose bumps—until it prickled with hundreds of tiny spiderlings alighting on me to seek their way in the world.
( The Spiders Web Part II , William H. Amos, presso Microscopy UK )
Journal of Animal Ecology , 1956
Although it has been known since the time of Aristotle that spiders can make airborne excursions , the first accurate observations were published by the pioneer British arachnologist, John Blackwall (1827).. during the last fifty years a number of arachnologists have published observations in this subject (Nielsen 1932, Braendegaard 1937, 1938, 1946, Bristowe 1929, 1939, Berland 1932, Smith 1904, Emerton 1908, 1919, McKeown 1952)... Glick was able to collect about 1500 specimens, including 4 at 5000 ft .
( Aerial Dispersal in a Known Spider Population , Eric Duffey, Journal of Animal Ecology , Vol. 25, No. 1, May, 1956, pp. 85-111, disponibile su JSTOR )
Journal of Arachnology , 1999
Bishop & Riechert (1990) used sticky traps, pitfall traps, and exclosures to demonstrate that 41-50% of the spider species found in their plots had arrived by aerial deposition, and that, in the course of the four-month growing seasons, the aerial deposition was occurring at a rate of at least 0.18 spider/day/m 2 . Although that estimate seems modest, it translates into an influx of 1800 spiders into a 1-ha field during each day of the growing season, and at total influx of about 2.16 x 10 5 spiders over the growing season.
...the occurrence of airborne spiders at high altitudes (Glick 1939; Gertsch 1979) and scores of km from the nearest land mass (Darwin 1839; Hardy & Cheng 1986)...
( An Aerial Lottery: The Physics of Ballooning in a Chaotic Atmosphere , Robert B. Suter, in Journal of Arachnology 27:281-293, 1999; disponibile presso Americanarachnology.org )
Charles Darwin in The Voyage of the Beagle , 1845
...in the morning the air was full of patches of the flocculent web [...]. The ship was sixty miles distant from the land [...]. Vast numbers of a small spider [...] were attached to the web. There must have been, I should suppose, some thousands on the ship. [...] The little aeronaut as Arrived soon as it was very active on the board [...]
(The Voyage of the Beagle , Charles Darwin, 1845)
BBC The Living Planet, 1984 The
Sky Above, the seventh installment of this famous documentary series presented by David Attenborough, shows images of spiders spread their wings. Attenborough then ascends in a balloon in search of insects and spiders that go out, carried by air currents, up to 6500 meters.
A Falcon Flies , romanzo di Wilbur Smith (1980)
Pagina 172: "There is a tiny spider no bigger than the head of a wax Vesta which lives in the papyrus banks of the delta. It spins a gossamer web on which it launches itself into the breeze in such numbers that the gossamer fills the sky in clouds, like the smoke from a raging bushfire, rising many hundreds of feet..."
Grazie a Nodens per la segnalazione.
