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Encyclopedia > Earthworm
Earthworm
Lumbricus terrestris, the Common European Earthworm
Lumbricus terrestris, the Common European Earthworm
Scientific classification
Kingdom: Animalia
Phylum: Annelida
Class: Oligochaeta
Order: Haplotaxida
Suborder: Lumbricina
Families

  Acanthodrilidae
  Ailoscolecidae
  Alluroididae
  Almidae
  Criodrilidae
  Eudrilidae
  Exxidae
  Glossoscolecidae
  Hormogastridae
  Kynotidae
  Lumbricidae
  Lutodrilidae
  Megascolecidae
  Microchaetidae
  Ocnerodrilidae
  Octochaetidae
  Sparganophilidae
  Tumakidae
The Earthworm is hip-hop group LPGs first album. ... Image File history File links Download high resolution version (750x729, 136 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Earthworm Lumbricus terrestris Haplotaxida ... Binomial name Lumbricus terrestris Linnaeus, 1758 Lumbricus terrestris (L.) is a large reddish worm native to Europe, but now also widely distributed elsewhere around the world (along with several other lumbricids), due to human introductions. ... Scientific classification redirects here. ... For other uses, see Animal (disambiguation). ... Classes and subclasses Class Polychaeta (paraphyletic?) Class Clitellata    Oligochaeta - Earthworms and others    Acanthobdellida    Branchiobdellida    Hirudinea - Leeches Class Myzostomida Class Archiannelida (polyphyletic) Class Echiura *Some authors consider the subclasses under Clitellata to be classes The annelids, collectively called Annelida, are a large phylum of animals, comprising the segmented worms, with about... This Tree of Life article needs to be cleaned up to conform to a higher standard of quality. ... -1... A notable peculiarity of the subfamily Alminae is a tendency to extensions of the body wall in the vicinity of or including the male pores. ... Eudrilid earthworms are restricted to Africa (Ethiopian Region) as natives. ... Glossoscolecidae is a large family of earthworms which has native representatives in South and Central America. ... Common genera Lumbricus Eisenia Eiseniella Allolobophora Aporrectodea Bimastos Dendrobaena Dendrodrilus (and more) The Lumbricidae is a family of earthworms which includes most of the well-known earthworm species. ... Genera See text. ... Sparganophilus, the only genus in the family Sparganophilidae, is a group of long slender limicolous (mud-dwelling) earthworms native to North America. ...

Earthworm is the usual name for the largest members of Oligochaeta (which is either a class or subclass depending on the author) in the phylum Annelida. In classical systems they were placed in the order Opisthopora, on the basis of the male pores opening to the outside of the body posterior to the female pores, even though the male segments are anterior to the female. Theoretical cladistic studies have supported placing them instead in the suborder Lumbricina of the order Haplotaxida. Folk names for earthworm include "dew-worm", "rainworm", "night crawler" and "angleworm" (due to its fishing bait use).[1] This Tree of Life article needs to be cleaned up to conform to a higher standard of quality. ... For the characters from System Shock 2, see The Many. ... It has been suggested that Clade be merged into this article or section. ...


Earthworms are also called megadriles (or big worms), as opposed to the microdriles (or small worms), which include the families Tubificidae, Lumbriculidae, and Enchytraeidae, among others. The megadriles are characterized by having a multilayered clitellum (which is much more obvious than the single-layered one of the microdriles), a vascular system with true capillaries, and male pores behind the female pores. Subfamilies Phallodrilinae Limnodriloidinae Rhyacodrilinae Tubificinae Phallodrilinae Limnodriloidinae Rhyacodrilinae Tubificinae The Tubificidae are a family of clitellate oligochaete worms like the sludge worm, Tubifex tubifex. ... The lumbriculidae are a family of microdrile oligochaetes common in fresh-water environments. ... The Enchytraeidae are a microdrile oligochaete family and include both terrestrial species known as potworms that live in highly organic environments and iceworms such as Mesenchytraeus solifugus that live in ice fields. ... In earth worms and other annelids, the Clitellum is a thickened glandular section of the body wall that secretes a viscid sac in which the eggs are deposited. ...

Contents

Anatomy

Earthworms have 9 hearts and a closed circulatory system. They have two main blood vessels that extend through the length of their body: a ventral blood vessel which leads the blood to the posterior end, and a dorsal blood vessel which leads to the other end. The dorsal vessel is contractile and pumps blood forward, where it is pumped into the ventral vessel by a series of "hearts" (aortic arches) which vary in number in the different taxa. A typical lumbricid will have 5 pairs of hearts; a total of 10. The blood is distributed from the ventral vessel into capillaries on the body wall and other organs and into a vascular sinus in the gut wall where gases and nutrients are exchanged. This arrangement may be complicated in the various groups by suboesophageal, supraoesophageal, parietal and neural vessels, but the basic arrangement holds in all earthworms. Earthworms eat in a unique way. Their mouth cavity connects directly into the digestive tract without any intermediate processes. Earthworms are decomposers feeding on undecayed leaf and other plant matter. For transport in plants, see Vascular tissue. ... In sciences dealing with the anatomy of animals, precise anatomical terms of location are necessary for a variety of reasons. ... In sciences dealing with the anatomy of animals, precise anatomical terms of location are necessary for a variety of reasons. ... Common genera Lumbricus Eisenia Eiseniella Allolobophora Aporrectodea Bimastos Dendrobaena Dendrodrilus (and more) The Lumbricidae is a family of earthworms which includes most of the well-known earthworm species. ...


Reproduction

Earthworm reproduction

Earthworms are hermaphrodites (both female and male organs within the same individual). They have testes, seminal vesicles and male pores which produce, store and release the sperm, and ovaries and ovipores. However, most also have one or more pairs of spermathecae (depending on the species) that are internal sacs which receive and store sperm from the other worm in copulation. Some species use external spermatophores for transfer instead. Copulation and reproduction are separate processes in earthworms. The mating pair overlap front ends ventrally and each exchanges sperm with the other. The cocoon, or egg case, is secreted by the clitellum, the external glandular band which is near the front of the worm, but behind the spermathecae. Some indefinite time after copulation, long after the worms have separated, the clitellum secretes the cocoon which forms a ring around the worm. The worm then backs out of the ring, and as it does so, injects its own eggs and the other worm's sperm into it. As the worm slips out, the ends of the cocoon seal to form a vaguely lemon-shaped incubator (cocoon) in which the embryonic worms develop. They emerge as small, but fully formed earthworms, except for a lack of the sexual structures, which develop later, namely, in about 60 to 90 days. They attain full size in about one year.[2] Some earthworm species are mostly parthenogenetic. Image File history File links Size of this preview: 800 × 533 pixelsFull resolution (1200 × 800 pixel, file size: 245 KB, MIME type: image/jpeg) Earthworms mating. ... Image File history File links Size of this preview: 800 × 533 pixelsFull resolution (1200 × 800 pixel, file size: 245 KB, MIME type: image/jpeg) Earthworms mating. ... For other uses, see Hermaphrodite (disambiguation). ... Categories: Stub | Andrology | Exocrine system | Reproductive system ... The spermatheca is a part of the female reproductive tract in insects, some molluscs, and certain other invertebrates. ... A spermatophore is a capsule or mass created by males of various invertebrate species, containing spermatozoa and transferred in entirety to the female during sex. ... A pair of lions copulating in the Maasai Mara, Kenya. ... For other uses, see Reproduction (disambiguation) Reproduction is the biological process by which new individual organisms are produced. ... In zootomy, several terms are used to describe the location of organs and other structures in the body of bilateral animals. ... In earth worms and other annelids, the Clitellum is a thickened glandular section of the body wall that secretes a viscid sac in which the eggs are deposited. ... The tough brown cocoon of an Emperor Gum Moth. ... For the religious belief, see Virgin Birth of Jesus. ...


Regeneration

Earthworms have the facility to replace or replicate lost segments, but this ability varies between species and depends on the extent of the damage. Stephenson (1930) devoted a chapter of his monograph to this topic, while G.E. Gates spent 20 years studying regeneration in a variety of species, but “because little interest was shown”, Gates (1972) only published a few of his findings that, nevertheless, show it is theoretically possible to grow two whole worms from a bisected specimen in certain species. Gates’s reports included:

  • Eisenia fetida (Savigny, 1826) with head regeneration, in an anterior direction, possible at each intersegmental level back to and including 23/24, while tails were regenerated at any levels behind 20/21 [1].
  • Lumbricus terrestris Linneus, 1758 replacing anterior segments from as far back as 13/14 and 16/17 but tail regeneration was never found.
  • Perionyx excavatus Perrier, 1872 readily regenerated lost parts of the body, in an anterior direction from as far back as 17/18, and in a posterior direction as far forward as 20/21.
  • Lampito mauritii Kinberg, 1867 with regeneration in anterior direction at all levels back to 25/26 and tail regeneration from 30/31; head regeneration was sometimes believed to be caused by internal amputation resulting from Sarcophaga sp. larval infestation.
  • Criodrilus lacuum Hoffmeister, 1845 also has prodigious regenerative capacity with ‘head’ regeneration from as far back as 40/41.[2]

An unidentified Tasmanian earthworm shown growing a second head is reported here: [3]. Binomial name Eisenia fetida (Savigny, 1826) [1] Eisenia fetida, known under various common names, including redworms, brandling worms, tiger worms and red wiggler worms, is a species of earthworm adapted to the environment of decaying organic material. ...


Behavior

Rainstorms

Earthworms are seen out of the dirt after large rain storms because the soil becomes too moist for them to survive. They need a moist environment to allow the diffusion of gases across their skin membrane, however if the soil becomes too moist the earthworms begin to drown in the water. To protect themselves from drowing they find higher, dry ground. This is why they are seen in places like driveways after a storm. However, after the storm they are sometimes unable to return to the moist soil and they dry up, and because their body is no longer moist enough to allow the diffusion of gases the earthworms suffocate. Image File history File links Question_book-3. ...


Earthworms are often observed to come to the surface in large numbers after a rainstorm. There are four theories for this behavior. This article is about precipitation. ...

An earthworm being eaten by an American Robin.
An earthworm being eaten by an American Robin.

The first is that the waterlogged soil has insufficient oxygen for the worms, so the earthworms come to the surface to get enough oxygen. However, this theory is rejected by some because earthworms can survive underwater for several hours if there is oxygen in the water. Image File history File linksMetadata Download high-resolution version (1680x1424, 1937 KB) This photo was taken by Ryan Bushby(HighInBC) with his Canon PowerShot S3 IS. To see more of his photos see his gallery. ... Image File history File linksMetadata Download high-resolution version (1680x1424, 1937 KB) This photo was taken by Ryan Bushby(HighInBC) with his Canon PowerShot S3 IS. To see more of his photos see his gallery. ... Binomial name Linnaeus, 1766 The American Robin (Turdus migratorius) is a migratory songbird of the thrush family. ...


Secondly, some species (notably Lumbricus terrestris) come to the surface to mate. Since this behavior is limited to a few species, as well as the fact that mating is not connected to rain, this theory does not seem very likely. Binomial name Lumbricus terrestris Linnaeus, 1758 Lumbricus terrestris (L.) is a large reddish worm native to Europe, but now also widely distributed elsewhere around the world (along with several other lumbricids), due to human introductions. ...


Third, the worms may be using the moist conditions on the surface to travel more quickly than they can underground, thus colonizing new areas more quickly. Since the relative humidity is higher during and after rain, they do not become dehydrated. This is a dangerous activity in the daytime, since earthworms die quickly when exposed to direct sunlight with its strong UV content, and are more vulnerable to predators such as birds. Note: Ultraviolet is also the name of a 1998 UK television miniseries about vampires. ... For other meanings of bird, see bird (disambiguation). ...


The fourth theory is that as there are many other organisms in the ground as well and they respire as any animal does; the carbon dioxide produced dissolves into the rainwater; it forms carbonic acid and the soil becomes too acidic for the worms and they come seek neutral nourishment on the surface.


Locomotion and importance to soil

Close up of an earthworm in garden soil
Close up of an earthworm in garden soil

Earthworms travel underground by the means of waves of muscular contractions which alternately shorten and lengthen the body. The shortened part is anchored to the surrounding soil by tiny claw-like bristles (setae) set along its segmented length. (Typically, earthworms have four pairs of setae for each segment but some genera are perichaetine, having a large number of setae on each segment.) The whole burrowing process is aided by the secretion of a slimy lubricating mucus. Worms can make gurgling noises underground when disturbed as a result of the worm moving through its lubricated tunnels as fast as it can. Earthworm activity aerates and mixes the soil, and is constructive to mineralization and nutrient uptake by vegetation. Certain species of earthworm come to the surface and graze on the higher concentrations of organic matter present there, mixing it with the mineral soil. Because a high level of organic matter mixing is associated with soil fertility, an abundance of earthworms is beneficial to the organic gardener. In fact as long ago as 1881 Charles Darwin wrote: It may be doubted whether there are many other animals which have played so important a part in the history of the world, as have these lowly organized creatures [3] Look up seta in Wiktionary, the free dictionary. ... It has been suggested that this article or section be merged with Organic horticulture. ... For other people of the same surname, and places and things named after Charles Darwin, see Darwin. ...


Benefits

The major benefits of earthworm activities to soil fertility can be summarized as:

  • Biological. In many soils, earthworms play a major role in converting large pieces of organic matter (e.g. dead leaves) into rich humus, and thus improving soil fertility. This is achieved by the worm's actions of pulling down below any organic matter deposited on the dried dirt(eg, leaf fall, manure, etc) either for food or when it needs to plug its burrow. Once in the burrow, the worm will shred the leaf and partially digest it, then mingle it with the earth by saturating it with intestinal secretions. Worm casts (see below) can contain 40% more humus than the top 6" of soil in which the worm is living.
  • Chemical. As well as dead organic matter, the earthworm also ingests any other soil particles that are small enough—including stones up to 1/20 of an inch (1.25mm) across—into its gizzard wherein minute fragments of grit grind everything into a fine paste which is then digested in the stomach. When the worm excretes this in the form of casts which are deposited on the surface or deeper in the soil, minerals and plant nutrients are made available in an accessible form. Investigations in the US show that fresh earthworm casts are 5 times richer in available nitrogen, 7 times richer in available phosphates and 11 times richer in available potash than the surrounding upper 6 inches (150 mm) of soil. In conditions where there is plenty of available humus, the weight of casts produced may be greater than 4.5 kg (10 lb) per worm per year, in itself an indicator of why it pays the gardener or farmer to keep worm populations high.
  • Physical. By its burrowing actions, the earthworm is of great value in keeping the soil structure open, creating a multitude of channels which allow the processes of both aeration and drainage to occur. Permaculture co-founder Bill Mollison points out that by sliding in their tunnels, earthworms "act as an innumerable army of pistons pumping air in and out of the soils on a 24 hour cycle (more rapidly at night)" [4]. Thus the earthworm not only creates passages for air and water to traverse, but is itself a vital component in the living biosystem that is healthy soil.

See Bioturbation.-1... This article does not cite any references or sources. ... For other uses of terms redirecting here, see US (disambiguation), USA (disambiguation), and United States (disambiguation) Motto In God We Trust(since 1956) (From Many, One; Latin, traditional) Anthem The Star-Spangled Banner Capital Washington, D.C. Largest city New York City National language English (de facto)1 Demonym American... General Name, symbol, number nitrogen, N, 7 Chemical series nonmetals Group, period, block 15, 2, p Appearance colorless gas Standard atomic weight 14. ... A phosphate, in inorganic chemistry, is a salt of phosphoric acid. ... Potash Potash (or carbonate of potash) is an impure form of potassium carbonate (K2CO3). ... Permaculture Mandala summarising the ethics and principles of permaculture design. ... Bill Mollison (born 1928 in Tasmania, Australia) is a researcher, author, scientist, teacher, naturalist and has been called the father of permaculture, an integrated system of design co-developed with David Holmgren that encompasses not only agriculture, horticulture, architecture and ecology but also economic systems, land access strategies and legal... In oceanography and limnology, the displacement and mixing of sediment particles by benthic fauna (animals) or flora (plants) is termed bioturbation. ...


The earthworm's existence cannot be taken for granted. Dr. W. E. Shewell Cooper observed "tremendous numerical differences between adjacent gardens" (Soil, Humus And Health), and worm populations are affected by a host of environmental factors, many of which can be influenced by good management practices on the part of the gardener or farmer. Dr. Shewell Cooper- organic gardener and pioneer of no dig cultivation systems, author of Soil, Humus and Health and founder of the Good Gardeners Association. ...


Darwin estimated that arable land contains up to 53,000 worms per acre (13/m²), but more recent research from Rothamsted Experimental Station has produced figures suggesting that even poor soil may support 250,000/acre (62/m²), whilst rich fertile farmland may have up to 1,750,000/acre (432/m²), meaning that the weight of earthworms beneath the farmer's soil could be greater than that of his livestock upon its surface. One thing is certain however: rich, fertile soil that is cared for organically and well-fed and husbanded by its steward will reap its reward in a healthy worm population, whilst denuded, overworked, and eroded land will almost certainly contain fewer, scrawny, undernourished specimens. To meet Wikipedias quality standards, this article or section may require cleanup. ... Buildings near the manor house The Rothamsted Experimental Station, one of the oldest agricultural research institutions in the world, is located at Harpenden in Hertfordshire, England. ...


Earthworms as invasive species

North America

A total of approximately 182 earthworm taxa in 12 families are reported from America north of Mexico, i.e., USA & Canada, of which 60 (ca. 33%) are exotic/introduced. Only two genera of Lumbricid earthworms are indigenous to North America while introduced genera have spread to areas where earthworms did not formerly exist, especially in the north where forest development relies on a large amount of undecayed leaf matter. When worms decompose that leaf layer, the ecology may shift making the habitat unsurvivable for certain species of trees, ferns and wildflowers. Currently there is no economically feasible method for controlling invasive earthworms in forests. Earthworms normally spread slowly, but can be quickly introduced by human activities such as construction earthmoving, or by fishermen releasing bait, or by plantings from other areas. Common genera Lumbricus Eisenia Eiseniella Allolobophora Aporrectodea Bimastos Dendrobaena Dendrodrilus (and more) The Lumbricidae is a family of earthworms which includes most of the well-known earthworm species. ...


Soils which have been invaded by earthworms can be recognized by an absence of palatable leaf litter. For example, in a forest with sugar maple - white ash - beech - northern red oak trees, only beech and oak leaves will be seen on the forest floor except during the autumn leaf-fall, as earthworms quickly devour maple and ash leaves. Basswood, dogwood, elm, poplar and tuliptree also produce palatable foliage. Binomial name Acer saccharum Marshall The Sugar Maple Acer saccharum is a prominent tree in the hardwood forests of eastern North America. ... Binomial name Fraxinus americana L. The White Ash (Fraxinus americana) is one of the largest of the ash genus Fraxinus, growing to 35 m tall. ... For other uses, see Beech (disambiguation). ... Binomial name Quercus rubra L. The Northern Red Oak or Champion Oak, Quercus rubra (syn. ... Basswood is the common name of timbers of Tilia species. ... Subgenera Cornus Benthamidia Swida The Dogwoods comprise a group of 30-50 species of deciduous woody plants (shrubs and trees) in the family Cornaceae, divided into one to nine genera or subgenera (depending on botanical interpretation). ... Species See Elm species, varieties, cultivars and hybrids Elms are deciduous and semi-deciduous trees making up the genus Ulmus, family Ulmaceae, found throughout the Northern Hemisphere from Siberia to Indonesia, Mexico to Japan. ... This article is about woody plants of the genus Populus. ... Species Liriodendron chinense (Hemsl. ...


Australia

Australia has 650 known species of native earthworm that survive in both rich and in nutrient-poor conditions where they may be sensitive to changes in the environment. Introduced species are commonly found in agricultural environments along with persistent natives. Most of the 75 or so exotics have been accidentally introduced into Australia. The total species numbers are predicted to exceed 2,000. [5]


Special habitats

While, as the name earthworm suggests, the main habitat of earthworms is in soil, the situation is more complicated than that. The brandling worm Eisenia fetida lives in decaying plant matter and manure. Arctiostrotus vancouverensis from Vancouver Island and the Olympic Peninsula is generally found in decaying conifer logs or in extremely acidic humus. Aporrectodea limicola and Sparganophilus and several others are found in mud in streams. Even in the soil species, there are special habitats, such as soils derived from serpentine which have an earthworm fauna of their own. Binomial name Eisenia fetida (Savigny, 1826) [1] Eisenia fetida, known under various common names, including redworms, brandling worms, tiger worms and red wiggler worms, is a species of earthworm adapted to the environment of decaying organic material. ... Vancouver Island is separated from mainland British Columbia by the Strait of Georgia and the Queen Charlotte Strait, and from Washington by the Juan De Fuca Strait. ... The Olympic Peninsula is the large arm of land in western Washington state that lies across Puget Sound from Seattle. ... Sparganophilus, the only genus in the family Sparganophilidae, is a group of long slender limicolous (mud-dwelling) earthworms native to North America. ... For other uses, see Serpentine (disambiguation). ...


Ecology

Earthworms are classified into one of three ecophysiological categories: epigeic, endogeic, or anecic. These refer, respectively, to leaf litter/compost dwelling worms; soil dwelling worms; and worms that construct permanent deep burrows, through which they visit the surface to obtain plant material for food, such as leaves.[6]


Earthworm populations depend on both physical and chemical properties of the soil, such as soil temperature, moisture, pH, salts, aeration and texture, as well as available food, and the ability of the species to reproduce and disperse. One of the most important environmental factors is pH, but earthworms vary in their preferences. Most earthworms favor neutral to slightly acidic soil. However, Lumbricus terrestris are still present in a pH of 5.4 and Dendrobaena octaedra at a pH of 4.3 and some Megascolecidae are present in extremely acid humic soils. Soil pH may also influence the numbers of worms that go into diapause. The more acid the soil, the sooner worms go into diapause, and remain in diapause the longest time at a pH of 6.4. For other uses, see PH (disambiguation). ... Genera See text. ... Diapause is a physiological state of dormancy with very specific triggering and releasing conditions; there are various definitions and contexts in which the term is used, but its most common application is in arthropods, especially insects. ...


Earthworms form the base of many food chains. They are preyed upon by many species of birds, e.g. starlings, thrushes, gulls, crows, and both European Robins and American Robins. Mammals such as hedgehogs and moles eat many earthworms as well. Earthworms are also eaten by many invertebrates such as ground beetles and other beetles, snails, slugs. Earthworms have many internal parasites including Protozoa, Platyhelminthes, Nematodes. They are found in many parts of earthworms' bodies such as blood, seminal vesicles, coelom, intestine, or in the cocoons. For other uses, see Bird (disambiguation). ... This article is about the bird family. ... Genera Some 20, see text Wikimedia Commons has media related to: Turdidae The Thrushes, family Turdidae, are a group of passerine birds that occur mainly but not exclusively in the Old World. ... “Seagull” redirects here. ... For other uses, see Crow (disambiguation). ... Binomial name (Linnaeus, 1758) Subspecies 7-10, see text. ... Binomial name Linnaeus, 1766 The American Robin (Turdus migratorius) is a migratory songbird of the thrush family. ... This article is about the spiny mammal. ... For other uses, see Mole. ... Genera Many genera; see text. ... For other uses, see Beetle (disambiguation). ... For other uses, see Snail (disambiguation). ... This article is about land slugs. ... A parasite is an organism that spends a significant portion of its life in or on the living tissue of a host organism and which causes harm to the host without immediately killing it. ... Leishmania donovani, (a species of protozoan) in a bone marrow cell (in Greek proto = first and zoa = animals) are one-celled eukaryotes (that is, unicellular microbes whose cells have membrane-bound nuclei) that commonly show characteristics usually associated with animals, mobility and heterotrophy. ... Classes Monogenea Trematoda Cestoda Turbellaria The flatworms (Platyhelminthes, Greek platy: flat; helminth: worm) are a phylum of relatively simple soft-bodied invertebrate animals. ... Classes Adenophorea    Subclass Enoplia    Subclass Chromadoria Secernentea    Subclass Rhabditia    Subclass Spiruria    Subclass Diplogasteria    Subclass Tylenchia The nematodes or roundworms (Phylum nematoda from Greek (nema): thread + -ode like) are one of the most common phyla of animals, with over 80,000 different described species (over 15,000 are parasitic). ... Coelom with Dermal Tissue One of the primary ways zoologists group animals has to do with the presence or absence of a coelom and how it is formed. ... In anatomy, the intestine is the segment of the alimentary canal extending from the stomach to the anus and, in humans and other mammals, consists of two segments, the small intestine and the large intestine. ... Cocoon has a number of meanings. ...


The application of chemical fertilizers, sprays and dusts can have a disastrous effect on earthworm populations. Nitrogenous fertilizers tend to create acid conditions, which are fatal to the worms, and often dead specimens are to be found on the surface following the application of substances like DDT, lime sulphur and lead arsenate. In Australia, the use of superphosphate on pastures almost completely wiped out the giant Gippsland earthworm. This does not cite any references or sources. ... For other uses, see DDT (disambiguation). ... ... Lead hydrogen arsenate, also called lead arsenate, acid lead arsenate or LA, chemical formula PbHAsO4, is an inorganic insecticide used primarily against the potato beetle. ... Superphosphate is a fertiliser produced by the action of concentrated Sulphuric Acid on ground phosphate rock. ... Pastureland Pasture is land with lush herbaceous vegetation cover used for grazing of ungulates as part of a farm or ranch. ... The Gippsland Earthworm (Megascolides australis), is one of the most fascinating of Australia’s 1000 native earthworm species. ...


Therefore, the most reliable way to maintain or increase the levels of worm population in the soil is to avoid the application of artificial chemicals. Adding organic matter, preferably as a surface mulch, on a regular basis will provide them with their food and nutrient requirements, and also creates the optimum conditions of heat (cooler in summer and warmer in winter) and moisture to stimulate their activity.


A recent threat to earthworm populations in the UK is the New Zealand Flatworm (Artiposthia triangulata), which feeds upon the earthworm, but in the UK has no natural predator itself. At present sightings of the New Zealand flatworm have been mainly localised, but this is no reason for complacency as it has spread extensively since its introduction in 1960 through contaminated soil and plant pots. Any sightings of the flatworm should be reported to the Scottish Crop Research Institute, which is monitoring its spread. The New Zealand Flatworm (Arthurdendyus triangulatus or Artioposthia triangulata ) is a large flatworm native to New Zealand. ... The Scottish Crop Research Institute or SCRI is a research institution dedicated to research in crop science. ...


Economic impact

Various species of worms are used in vermiculture, the practice of feeding organic waste to earthworms to decompose (digest) it, a form of composting by the use of worms. These are usually Eisenia fetida (or its close relative Eisenia andrei) or the Brandling worm, also known as the Tiger worm or Red Wiggler, and are distinct from soil-dwelling earthworms. Vermicompost (or worm compost) is produced by feeding kitchen scraps and shredded newspaper to worms. ... A handful of compost A double-wide bin with compost at different stages of decomposition Compost is the aerobically decomposed remnants of organic materials. ... Binomial name Eisenia fetida (Savigny, 1826) [1] Eisenia fetida, known under various common names, including redworms, brandling worms, tiger worms and red wiggler worms, is a species of earthworm adapted to the environment of decaying organic material. ...


Earthworms are sold all over the world. The earthworm market is sizable. According to Doug Collicut (see "Nightcrawler" link below), "In 1980, 370 million worms were exported from Canada, with a Canadian export value of $13 million and an American retail value of $54 million."


Earthworms are also sometimes sold as food for human consumption. Noke is a culinary term used by the Māori of New Zealand to refer to earthworms which are considered delicacies. Noke is a culinary term used by the Māori of New Zealand to refer to earthworms, some types of native worms are considered delicacies. ... This article is about the Māori people of New Zealand. ...


Taxonomy and main geographic origins of earthworms

Main families :

  • Lumbricidae : temperate areas of Northern Hemisphere from Canada to Japan, mostly Eurasia
  • Hormogastridae : Europe
  • Sparganophilidae : North America
  • Almidae : Africa, South America
  • Acanthodrilidae : Africa, midland and southeastern North America, Central and South America, Australia and Oceania
  • Ocnerodrilidae : Central and South America, Africa
  • Octochaetidae : Central/South America, western Africa, India, New Zealand, Australia
  • Exxidae : Central America/Caribbean
  • Megascolecidae : South East Asia, Australasia and Oceania, northwestern North America
  • Glossoscolecidae : Central and northern South America
  • Eudrilidae : Africa

Common genera Lumbricus Eisenia Eiseniella Allolobophora Aporrectodea Bimastos Dendrobaena Dendrodrilus (and more) The Lumbricidae is a family of earthworms which includes most of the well-known earthworm species. ... Sparganophilus, the only genus in the family Sparganophilidae, is a group of long slender limicolous (mud-dwelling) earthworms native to North America. ... A notable peculiarity of the subfamily Alminae is a tendency to extensions of the body wall in the vicinity of or including the male pores. ... Genera See text. ... Glossoscolecidae is a large family of earthworms which has native representatives in South and Central America. ... Eudrilid earthworms are restricted to Africa (Ethiopian Region) as natives. ...

References

  1. ^ "earthworm."Encyclopædia Britannica. 2008. Encyclopædia Britannica 2006 Ultimate Reference Suite DVD 29 Apr. 2008
  2. ^ Ibid
  3. ^ Charles Darwin, The formation of vegetable mould through the action of worms, with observations on their habits. Found at Project Gutenberg Etext Formation of Vegetable Mould, by Darwin
  4. ^ Mollison, Bill, Permaculture- A Designer's Manual, Tagari Press, 1988
  5. ^ Blakemore, Rob, Diversity of exotic earthworms in Australia - a status report. Transactions of the Royal Zoological Society of New South Wales, 1999
  6. ^ Earthworms: Renewers of Agroecosystems (SA Fall, 1990 (v3n1))

For other people of the same surname, and places and things named after Charles Darwin, see Darwin. ...

Further reading

Edwards, Clive A. (Ed.) Earthworm Ecology. Boca Raton: CRC Press, 2004. Second revised edition. ISBN 084931819X


Lee, Keneth E. Earthworms: Their Ecology and Relationships with Soils and Land Use. Academic Press. Sydney, 1985. ISBN 0-12-440860-5


Stewart, Amy. The Earth Moved: On the Remarkable Achievements of Earthworms. Chapel Hill, N.C.: Algonquin Books, 2004. ISBN 1-56512-337-9


See also

The drilosphere is the part of the soil influenced by earthworm secretions and castings[1]. Specifically, it is the fraction of soil which has gone through the digestive tract of earthworms[2]; or the lining of an earthworm burrow[3]. The average thickness of the drilosphere (lining of an earthworm... Common genera Lumbricus Eisenia Eiseniella Allolobophora Aporrectodea Bimastos Dendrobaena Dendrodrilus (and more) The Lumbricidae is a family of earthworms which includes most of the well-known earthworm species. ... Genera See text. ... Sparganophilus, the only genus in the family Sparganophilidae, is a group of long slender limicolous (mud-dwelling) earthworms native to North America. ... Soil life or soil biota is a collective term for all the organisms living within the soil. ... Gilbert White (July 18, 1720 – June 26, 1793) was a pioneering naturalist and ornithologist. ... Noke is a culinary term used by the Māori of New Zealand to refer to earthworms, some types of native worms are considered delicacies. ... Terra preta (which means dark soil in Portuguese), refers to expanses of very dark soils found in the Amazon Basin. ...

External links

  • Earthworm Digest A great informational website and magazine
  • Infography about Earthworms
  • How to Make a Worm Farm Good for Composting and Fishing
  • Kids Discovery
  • Earthworm Information (UC Davis)
  • earthworm on Encyclopedia.com
  • Biology of the Night Crawler (Lumbricus terrestris)
  • WormWatch - Field guide to earthworms
  • New Zealand flatworm page (UK Govt.)
  • New Zealand flatworm page (HDRA)
  • Worm Watch Canadian worm awareness and appreciation site, with detailed worm anatomy.
  • Minnesota Invasive Earthworms Minnesota DNR information on the negative impacts of earthworms
  • Lumbricidae keys and Dichogastrid checklist
  • web-book: Earthworms of Hungary
  • Opuscula Zoologica Budapest, online papers on earthworm taxonomy
  • A Series of Searchable Texts on Earthworm Biodiversity, Ecology and Systematics from Various Regions of the World
  • Earthworms as pests and otherwise hosted by the UNT Government Documents Department
  • Third International Oligochaete Taxonomy Meeting, Platres, Cyprus, April 2nd to 6th, 2007
  • Short comments on the Levant earthworm fauna

  Results from FactBites:
 
earthworm. The Columbia Encyclopedia, Sixth Edition. 2001-05 (461 words)
Earthworms burrow in the ground, swallowing soil from which the organic material is extracted and ground up in the gizzard and depositing the residue as castings outside the burrow.
Earthworms are also used as live bait and are eaten by some peoples—such as the Maoris, who consider certain species delicacies.
Earthworm castings bring to the surface from 7 to 18 tons of soil per acre annually.
  More results at FactBites »

 
 

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