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Spider Cannibalism
Spider cannibalism is the act of a spider consuming all or part of another individual of the same species as food. In the majority of cases a female spider kills and eats a male before, during, or after copulation. Cases in which males eat females are rare. Females eating males Many cultures, such as South Africa and Slovakia, believe that the male (usually significantly smaller than the female, down to 1% of her size as seen in ''Tidarren sisyphoides'') is likely to be killed by the female after the coupling, or sometimes even before intercourse has been initiated. This supposed propensity is what gave the black widow spider, ''Latrodectus mactans'', its name. However, the three species of North American black widows do not usually kill the male (although they have been known to do so). Males can sometimes even live in the web of a female for a period without being harmed in any way. The male Australian redback spider ''Latrodectus hasselti'' is killed by the female after he i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cannibalization(silk Spider)
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Cannibalization or cannibalisation may refer to: * Cannibalization (fiction), adapting, borrowing or stealing plots, characters, themes or ideas from one story for use in another or from one medium to another * Cannibalization (marketing), the introduction of a new product that harms sales of an older product by the same producer * Cannibalization (parts), the use of parts from one device to repair another See also * Cannibal (other) * Cannibalism (other) Cannibalism is the act of one individual of a species consuming all or part of another individual of the same species as food. Cannibalism may also refer to: Types of cannibalism * Cannibalism in poultry * Filial cannibalism * Human cannibalism ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sexual Dimorphism
Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most animals and some plants. Differences may include secondary sex characteristics, size, weight, colour, markings, or behavioural or cognitive traits. These differences may be subtle or exaggerated and may be subjected to sexual selection and natural selection. The opposite of dimorphism is ''monomorphism'', which is when both biological sexes are phenotypically indistinguishable from each other. Overview Ornamentation and coloration Common and easily identified types of dimorphism consist of ornamentation and coloration, though not always apparent. A difference in coloration of sexes within a given species is called sexual dichromatism, which is commonly seen in many species of birds and reptiles. Sexual selection leads to the exaggerated dim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spiders
Spiders ( order Araneae) are air-breathing arthropods that have eight legs, chelicerae with fangs generally able to inject venom, and spinnerets that extrude silk. They are the largest order of arachnids and rank seventh in total species diversity among all orders of organisms. Spiders are found worldwide on every continent except for Antarctica, and have become established in nearly every land habitat. , 50,356 spider species in 132 families have been recorded by taxonomists. However, there has been debate among scientists about how families should be classified, with over 20 different classifications proposed since 1900. Anatomically, spiders (as with all arachnids) differ from other arthropods in that the usual body segments are fused into two tagmata, the cephalothorax or prosoma, and the opisthosoma, or abdomen, and joined by a small, cylindrical pedicel, however, as there is currently neither paleontological nor embryological evidence that spiders ever had a separate t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sexual Cannibalism
Sexual cannibalism is when an animal, usually the female, cannibalizes its mate prior to, during, or after copulation.Polis, G.A. & Farley, R.D. Behavior and Ecology of Mating in the journal of Arachnology 33-46 (1979). It is a trait observed in many arachnid orders and several insect orders. Several hypotheses to explain this seemingly paradoxical behavior have been proposed. The adaptive foraging hypothesis,Blamires, S.J. Nutritional implications for sexual cannibalism in a sexually dimorphic orb web spider. Austral Ecology 36, 389-394 (2011). aggressive spillover hypothesisArnqvist, G. Courtship behaviour and sexual cannibalism in the semi-aquatic fishing spider, DOLOMEDES FIMBRIATUS (CLERCK) (ARANEAE: PISAURIDAE).pdf. The journal of Arachnology 20, 222-226 (1992). and mistaken identity hypothesisGould, S. Only his wings remained. Natural History 93, 10-18 (1984). are among the proposed hypotheses to explain how sexual cannibalism evolved. This behavior is believed to have evolve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cannibalism (zoology)
Cannibalism is the act of consuming another individual of the same species as food. Cannibalism is a common ecological interaction in the animal kingdom and has been recorded in more than 1,500 species. Human cannibalism is well documented, both in ancient and in recent times. The rate of cannibalism increases in nutritionally poor environments as individuals turn to members of their own species as an additional food source.Elgar, M.A. & Crespi, B.J. (1992) ''Cannibalism: ecology and evolution among diverse taxa'', Oxford University Press, Oxford ngland New York. Cannibalism regulates population numbers, whereby resources such as food, shelter and territory become more readily available with the decrease of potential competition. Although it may benefit the individual, it has been shown that the presence of cannibalism decreases the expected survival rate of the whole population and increases the risk of consuming a relative. Other negative effects may include the increased ri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phidippus Johnsoni
''Phidippus johnsoni'', the red-backed jumping spider, is one of the largest and most commonly encountered jumping spiders of western North America. It is not to be confused with the unrelated and highly venomous redback spider (''Latrodectus hasselti''). Description Adults tend to be about a centimeter in length. Both sexes have a bright red abdomen; the female has an additional black central stripe. The chelicerae of both sexes are of a shining teal color. The rest of the body is mostly black. It is one of the species of jumping spiders that are mimics of mutillid wasps in the genus ''Dasymutilla'' (commonly known as "velvet ants"); several species of these wasps are similar in size and coloration, and possess a very painful sting. Distribution The distribution of ''P. johnsoni'' is bounded by the Great Plains, the Pacific Ocean, northern Mexico, and southern Canada. It occurs from sea level to tree line, occupying relatively dry habitats such as coastal dunes or oak woodl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pholcus Phalangioides
''Pholcus phalangioides'', commonly known as daddy long-legs spider or long-bodied cellar spider, is a spider of the family Pholcidae. It is also known as the skull spider, since its cephalothorax resembles a human skull. This is the only spider species described by the Swiss entomologist Johann Kaspar Füssli, who first recorded it in 1775. Its common name of "daddy long-legs" should not be confused with a different arachnid group with the same common name, the harvestman (Opiliones). Females have a body length of about 8 mm while males tend to be slightly smaller. The length of the spider's legs are on average 5 or 6 times the length of its body. ''Pholcus phalangioides'' has a habit of living on the ceilings of rooms, caves, garages or cellars. This spider species is considered beneficial in parts of the world because it preys on other spiders, including species considered dangerous such as redback spiders. ''Pholcus phalangioides'' is known to be harmless to humans a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Segestria Florentina
''Segestria florentina'' is the biggest European segestriid spider. Some vernacular names are green-fanged tube web spider and cellar spider, although the latter is not exclusive to this species. Description Females can reach a body length of 22 mm, males up to 15 mm. This species is much darker than others of the same genus. While subadult spiders have a greyish opisthosoma with a marking similar to '' Segestria senoculata'', adults are of a uniform black, sometimes with a green iridescent shine, especially on the chelicerae,Bellmann, H. (1997). Kosmos-Atlas Spinnentiere Europas. ''Kosmos''. which reflect with a striking green. The sexes are similar. Adults occur from June to November. Habits They spin a tubular web, often in cracks of buildings. Six or more silken lines radiate from it, and the spider waits in the entrance, touching the lines with the frontal six legs. Prey triggering these lines get caught, and the spider immediately retreats again to eat it. Howev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stegodyphus Lineatus
''Stegodyphus lineatus'' (desert spider) is the only European species of the spider genus ''Stegodyphus.'' Male ''S. lineatus'' can grow up to 12 mm long while females can grow up to 15 mm. The colour can range from whitish to almost black. In most individuals the opisthosoma is whitish with two broad black longitudinal stripes. Males and females look similar, but the male is generally richer in contrast and has a bulbous forehead. The species name refers to the black lines on the back of these spiders (not present in all individuals). ''S. lineatus'' is found in the southern Mediterranean region of Europe (south of Barcelona, southern Greece including Crete) and as far east as Tajikistan. Behavior ''Stegodyphus lineatus'' can be found in desert habitats, especially in the Negev desert in Israel and dry Mediterranean climates. These spiders build a web between twigs, mostly residing in low thorny shrubs. They prefer to build their webs in prey concentrated ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of Arachnology
The American Arachnological Society (AAS) is a scientific organization founded in 1972 in order to promote the study of arachnids by seeking to achieve closer cooperation and understanding between amateur and professional arachnologists along with publication of the ''Journal of Arachnology.'' The society holds annual meetings around the United States and membership is open to all individuals who share the common objectives held by the society. Journal The AAS publishes the ''Journal of Arachnology''. Selected publications * See also * International Society of Arachnology The International Society of Arachnology (ISA) promotes the study of arachnids and the exchange of information among researchers in this field. It acts as an umbrella organisation for regional societies and individuals interested in spiders, and ... References External links AAS Constitution {{authority control Arachnological societies Environmental organizations based in Rhode Island Zoology organi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evarcha Culicivora
''Evarcha culicivora'' is a species of jumping spider (family Salticidae) found only around Lake Victoria in Kenya and Uganda. At maturity, ''E. culicivora'' spiders have an average size of 5 mm for both males and females. The range in size for either sex is quite small, with females being only slightly larger on average (4–7 mm compared to 3–6 mm). It is commonly known as the vampire spider because it indirectly desires the blood of vertebrates. It does this by predating on blood-sucking female mosquitoes in the genus ''Anopheles,'' the mosquito responsible for transmitting malaria in the region, as well as other vector-borne diseases in humans. Experimentally, these spiders are considered ''Anopheles'' specialists. ''E. culicivora'' has an association with the native plants ''Lantana camara'' and ''Ricinus, Ricinus communis''. They consume the nectar for food and preferentially use these plants as a location for courtship. The mating interact ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allocosa Brasiliensis
''Allocosa brasiliensis'' is a burrowing wolf spider species from southern South America. Long known to science, it remained almost unstudied until its unusual sexual behavior was described in the early 21st century.BBC News 2011-APR-12Cannibal wolf spiders are ladykillers/ref> This ground-dwelling spider is native to mainly coastal areas, from southeastern Brazil via Uruguay and Argentina to southern Chile, though its known occurrences are patchy. To what extent it is found on the Atlantic coast south of the Río de la Plata remains largely unknown, for example. While the males have been known for over a century, the females were only described in 1980. Description ''A. brasiliensis'' is a mid-sized cryptic light brown spider of robust build, with a body size of well over 1 cm (0.5 in and more) when fully grown, up to almost twice this size in the largest specimens. The cephalothorax has an inconspicuous darker stripe pattern reminiscent of that found in many lycosids, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
