Snails

Snail also refers to a chess engine; see Snail (chess) as well as a power source for a rotary snowplow. ? Snails Scientific classification Kingdom: Animalia Subkingdom: Metazoa Phylum: Mollusca Class: Gastropoda Giant African Snail (Achatina fulica) The name snail applies to most members of the molluscan class Gastropoda that have coiled shells. Other gastropods, which lack a conspicuous shell, are commonly called slugs, and are scattered throughout groups that primarily include snails. Snails are found in freshwater, marine, and terrestrial environments. While most people are familiar with only terrestrial snails, the majority of snails are not terrestrial. Snails with lungs belong to the group Pulmonata, while those with gills belong to the Paraphyletic group. Contents 1 Physical characteristics 2 Habitat 3 Diet 4 Reproduction 5 Predators 6 Lifespan 7 Control (Garden Pests) 8 Snails as Food 9 Trivia 10 External links Physical characteristics Brown garden snail English garden snail Snails move like worms by alternating body contractions with stretching, with a proverbially low speed. They produce mucus in order to aid locomotion by reducing friction. The mucus also reduces the snail's risk of injury and helps keep away potentially dangerous insects like ants. When retracted into their shells, snails cover the entrance with a 'trapdoor' like structure called an operculum. In winter some snail species hibernate in their shells by closing the opening with a thin shell-like plate that they build only for this use and destroy in spring. Even some slug species build a shell-like object below their upper skin. Snails come in a range of different sizes. The largest land snail is the Giant African Snail (Achatina achatina; Family Achatinidae), which can measure up to 30 cm. Pomacea maculata (Family Ampullariidae), or Giant Apple Snail is the largest freshwater snail, with its size reaching 15 cm diameter and over 600 g weight. The biggest of all snails is Syrinx aruanus, a marine species living in Australia. Shell lengths up to 1 m have been reported. Snail shells, like those of the Nautilus, are one example of the appearance of the phi, the golden ratio, in nature. Patterns on shells of certain sea snails (Conus, Cymbiola) are formed by biological version of cellular automata. Habitat As one of the largest classes of animals, snails can be found throughout the world. They are found in freshwater, marine, and terrestrial environments. The majority of the world's snails live in the oceans and new species are being discovered regularly. Terrestrial snails prefer damp areas around vegetation which they can use for cover during the day. Diet A snail's diet varies by species. Terrestrial snails such as garden snails generally eat young plant shoots or bark, or decaying vegetative matter. Carnivorous snails, such as the Decollate Snail feed on other snails. Snails eat by using their radula, or scraping tongue, to shear their food. Reproduction Some snails are hermaphrodites, producing both spermatozoa and ova. Others, such as Apple Snails, are either male or female. Prolific breeders, snails in pairs inseminate each other to internally fertilize their ova. Each brood may consist of up to 100 eggs. Garden snails bury their eggs in shallow topsoil primarily while the weather is warm and damp. After 2 to 4 weeks of favorable weather, these eggs hatch and the young emerge. Snails may lay eggs as often as once a month. Predators Snails have many natural predators, including ground beetles, snakes, toads, turtles, and birds like chickens, ducks and geese, and even a predatory caterpillar. Snails are widely used as human food (often known as escargots) in Europe, Asia and Africa. Two species commonly eaten in Europe are the Burgundy snail (Helix pomatia) and the brown garden snail (Helix aspersa) also known as the European brown snail. Lifespan The lifespan of snails varies from species to species. In the wild, Achatinidae snails live around 5 to 7 years and Helix snails live about 2 to 3 years. Aquatic Apple Snails live only a year or so. Most deaths are due to predators or parasites. As noted at the following address, snails have lived beyond this lifespan: "more than 30 years" http://www.weichtiere.at/Mollusks/Schnecken/weinberg.html Control (Garden Pests) Terrestrial snails and slugs are generally both migratory and nocturnal, thus difficult to control. Common methods of control include shallow dishes filled with beer, and the use of molluscicides. Snails as Food Snails are eaten as food in some parts of the world. The most well-known example of this is French cuisine. In France, three species are ordinarily eaten: Helix pomatia, the Burgundy Snail, prepared in its shell, with parsley butter. Typical size: 40 to 55 mm for an adult weight of 25 to 45 g. Typically found: in Burgundy. Helix aspersa : Helix aspersa aspersa is cooked in many different ways, according to different local traditions. Typical size: 28 to 35 mm for an adult weight of 7 to 15 g. Typically found: Mediterranean countries (Europe and North Africa) and the French Atlantic coast. Helix aspersa maxima . Typical size 40 to 45 mm for an average weight of 20 to 30 g. Typically found: in North Africa. Snails are also popular in Portugal, where they are called "caracóis" (Portuguese for "snails"), and served in cheap snack houses and taverns, usually boiled with garlic. Hélicicultures are snail farms. http://www.weichtiere.at/Mollusks/Schnecken/weinberg.html found at the previous link, "In nature they almost everywhere are put under protection (at least the Roman snail must not be collected any more), but especially the Roman snail and the garden snail (Cornu aspersum) are cultivated on snail farms (Hélicicultures). " http://www.weichtiere.at/Mollusks/Schnecken/land/weinberg/zucht.html Trivia In addition to being a common metaphor for a slow person, the snail is traditionally considered in many countries to predict the weather with its behaviour. In Finland this has led to a rhyme, where the snail is asked to show his tentacles. If the snail wears his "horns" high, tomorrow will be fine weather. Lilla snigel Lilla snigel, akta dej, akta dej, akta dej, annars tar jag dej. Snail is also the name of the Ultimate Frisbee team for the State University of New York at Geneseo. A snail can withstand the force of air at over 75 Mph (120 km/h) whilst still being able to move across the bonnet of the moving vehicle at the same time. External links Snail eating Brown garden snail Molluscs Kiddyhouse.com page on snails Snails as pets The trail of the snail AppleSnail.Net Lilla snigel Wikimedia Commons has media related to: ]] Search Term: "Snail" Categories: Gastropods

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