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Wheel Spider
The wheel spider or golden wheel spider (''Carparachne aureoflava''), is a huntsman spider native to the Namib Desert of Southern Africa. This spider should not be confused with ''Leucorchestris arenicola'', a spider sharing the same common name as well as the same locale. The spider escapes parasitic Spider wasp, pompilid wasps by flipping onto its side and rotating locomotion in living systems, cartwheeling down sand dunes at speeds of up to 44 turns per second. Characteristics Wheel spiders are up to 20 mm in size, with males and females the same size. The wheel spider is a nocturnal, free-ranging hunter, coming out at night to prey on insects and other small invertebrates. Its bite is mildly venomous, but the spider is not known to be harmful to humans. The wheel spider does not produce a web. Its principal line of defence against predation is to bury itself in a silk-lined burrow extending 40–50 cm deep. During the process of digging its burrow, the spider can s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peter Lawrence (biologist)
Peter Anthony Lawrence (born 23 June 1941) is a British developmental biologist at the Laboratory of Molecular Biology and the Zoology Department of the University of Cambridge. He was a staff scientist of the Medical Research Council (UK), Medical Research Council from 1969 to 2006. Education Lawrence was educated at Wennington School in Wetherby, and then at St Catharine's College, Cambridge on a Harkness Fellowship; he gained his doctorate as a student of Vincent Wigglesworth for work on Large milkweed bug, ''Oncopeltus fasciatus'' (milkweed bug) Career and research Lawrence's main discoveries lie in trying to understand what type of information is required to shape an animal and generate a pattern (such as on a butterfly wing or a fingerprint). He is the principal advocate of the idea that cells in a gradient of a morphogen develop according to their local concentration of the morphogen and that this mechanism is used to generate patterns of cells. Together with Ginés Mor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Huntsman Spider
Huntsman spiders, members of the family Sparassidae (formerly Heteropodidae), are known by this name because of their speed and mode of hunting. They are also called giant crab spiders because of their size and appearance. Larger species sometimes are referred to as wood spiders, because of their preference for woody places (forests, mine shafts, woodpiles, wooden shacks). In southern Africa the genus '' Palystes'' are known as rain spiders or lizard-eating spiders. Commonly, they are confused with baboon spiders from the Mygalomorphae infraorder, which are not closely related. More than a thousand Sparassidae species occur in most warm temperate to tropical regions of the world, including much of Australasia, Africa, Asia, the Mediterranean Basin, and the Americas. Several species of huntsman spider can use an unusual form of locomotion. The wheel spider (''Carparachne aureoflava'') from the Namib uses a cartwheeling motion which gives it its name, while '' Cebrennus rechen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Namib Desert
The Namib ( ; pt, Namibe) is a coastal desert in Southern Africa. The name is of Khoekhoegowab origin and means "vast place". According to the broadest definition, the Namib stretches for more than along the Atlantic coasts of Angola, Namibia, and South Africa, extending southward from the Carunjamba River in Angola, through Namibia and to the Olifants River (Western Cape), Olifants River in Western Cape, South Africa. The Namib's northernmost portion, which extends from the Angola-Namibia border, is known as Moçâmedes Desert, while its southern portion approaches the neighboring Kalahari Desert. From the Atlantic coast eastward, the Namib gradually ascends in elevation, reaching up to inland to the foot of the Great Escarpment, Southern Africa, Great Escarpment. Annual precipitation ranges from in the most arid regions to at the escarpment, making the Namib the only true desert in southern Africa. Having endured Desert climate, arid or Semi-arid climate, semi-arid cond ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Southern Africa
Southern Africa is the southernmost subregion of the African continent, south of the Congo and Tanzania. The physical location is the large part of Africa to the south of the extensive Congo River basin. Southern Africa is home to a number of river systems; the Zambezi River being the most prominent. The Zambezi flows from the northwest corner of Zambia and western Angola to the Indian Ocean on the coast of Mozambique. Along the way, the Zambezi River flows over the mighty Victoria Falls on the border between Zambia and Zimbabwe. Victoria Falls is one of the largest waterfalls in the world and a major tourist attraction for the region. Southern Africa includes both subtropical and temperate climates, with the Tropic of Capricorn running through the middle of the region, dividing it into its subtropical and temperate halves. Countries commonly included in Southern Africa include Angola, Botswana, the Comoros, Eswatini, Lesotho, Madagascar, Malawi, Mauritius, Mozambique, Namib ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leucorchestris Arenicola
''Leucorchestris arenicola,'' commonly called the dancing white lady spider, is a huntsman spider in the family ''Sparassidae'' and genus '' Leucorchestris.'' It is commonly found in the Namib desert of Namibia. It is often mistaken with the similarly named ''Carparachne aureoflava,'' or more commonly known as the wheel spider from the same location. ''L. arenicola'' relies on seismic vibrations, called drumming, for communication. It taps its foremost legs on the sand to send messages to other white lady spiders. Male ''L. arenicola'' will travel over 50 m in one night searching for a mate. If they find a mate, they must be extremely careful, for drumming the wrong message can be deadly. One of the major features that characterizes its nocturnal behavior is its specialized vision, using eight eyes in different orientations to capture a panoramic view of the surroundings. ''L. arenicola'' spiders use temporal summation in order to be able to see dim lighting during night-time ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spider Wasp
Wasps in the family Pompilidae are commonly called spider wasps, spider-hunting wasps, or pompilid wasps. The family is cosmopolitan, with some 5,000 species in six subfamilies. Nearly all species are solitary (with the exception of some group-nesting Ageniellini), and most capture and paralyze prey, though members of the subfamily Ceropalinae are kleptoparasites of other pompilids, or ectoparasitoids of living spiders. In South America, species may be referred to colloquially as or , though these names can be generally applied to any very large stinging wasps. Furthermore, in some parts of Venezuela and Colombia, it is called , or "horse killers", while in Brazil some particular bigger and brighter species of the general kind might be called /, or "throat locker". Morphology Like other strong fliers, pompilids have a thorax modified for efficient flight. The metathorax is solidly fused to the pronotum and mesothorax; moreover, the prothorax is best developed in Pompilidae a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rotating Locomotion In Living Systems
Rotation, or spin, is the circular movement of an object around a '' central axis''. A two-dimensional rotating object has only one possible central axis and can rotate in either a clockwise or counterclockwise direction. A three-dimensional object has an infinite number of possible central axes and rotational directions. If the rotation axis passes internally through the body's own center of mass, then the body is said to be ''autorotating'' or ''spinning'', and the surface intersection of the axis can be called a ''pole''. A rotation around a completely external axis, e.g. the planet Earth around the Sun, is called ''revolving'' or ''orbiting'', typically when it is produced by gravity, and the ends of the rotation axis can be called the ''orbital poles''. Mathematics Mathematically, a rotation is a rigid body movement which, unlike a translation, keeps a point fixed. This definition applies to rotations within both two and three dimensions (in a plane and in space, r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dune
A dune is a landform composed of wind- or water-driven sand. It typically takes the form of a mound, ridge, or hill. An area with dunes is called a dune system or a dune complex. A large dune complex is called a dune field, while broad, flat regions covered with wind-swept sand or dunes with little or no vegetation are called ''ergs'' or ''sand seas''. Dunes occur in different shapes and sizes, but most kinds of dunes are longer on the stoss (upflow) side, where the sand is pushed up the dune, and have a shorter ''slip face'' in the lee side. The valley or trough between dunes is called a ''dune slack''. Dunes are most common in desert environments, where the lack of moisture hinders the growth of vegetation that would otherwise interfere with the development of dunes. However, sand deposits are not restricted to deserts, and dunes are also found along sea shores, along streams in semiarid climates, in areas of glacial outwash, and in other areas where poorly cemented sa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cape Town
Cape Town ( af, Kaapstad; , xh, iKapa) is one of South Africa's three capital cities, serving as the seat of the Parliament of South Africa. It is the legislative capital of the country, the oldest city in the country, and the second largest (after Johannesburg). Colloquially named the ''Mother City'', it is the largest city of the Western Cape province, and is managed by the City of Cape Town metropolitan municipality. The other two capitals are Pretoria, the executive capital, located in Gauteng, where the Presidency is based, and Bloemfontein, the judicial capital in the Free State, where the Supreme Court of Appeal is located. Cape Town is ranked as a Beta world city by the Globalization and World Cities Research Network. The city is known for its harbour, for its natural setting in the Cape Floristic Region, and for landmarks such as Table Mountain and Cape Point. Cape Town is home to 66% of the Western Cape's population. In 2014, Cape Town was named the best place ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gobabeb
The Gobabeb Namib Research Institute, short: Gobabeb, is a centre for dry land training and research in Namibia. It is located in the Namib Desert, south-east of Walvis Bay. Gobabeb was founded by the Austrian entomologist Charles Koch in 1962. Since 1998 Gobabeb has been a joint venture between the ''Ministry of Environment and Tourism'' (MET) and the ''Desert Research Foundation Namibia'' (DRFN). Gobabeb conducts research in the fields of climate, ecology and geomorphology. It also tests, demonstrates and promotes appropriate technologies. By conducting training courses, Gobabeb aims to improve the public awareness and knowledge of dry land ecology and environmental issues. The station consists of permanent researchers, students, and interns, as well as short time visitors such as school and university groups, and tourists. Gobabeb also hosts film crews, journalists and artists. Station The Station is located south-east of Walvis Bay in Namibia's largest nature rese ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rolling Animals
Rolling is a type of motion that combines rotation (commonly, of an axially symmetric object) and translation of that object with respect to a surface (either one or the other moves), such that, if ideal conditions exist, the two are in contact with each other without sliding. Rolling where there is no sliding is referred to as ''pure rolling''. By definition, there is no sliding when there is a frame of reference in which all points of contact on the rolling object have the same velocity as their counterparts on the surface on which the object rolls; in particular, for a frame of reference in which the rolling plane is at rest (see animation), the instantaneous velocity of all the points of contact (e.g., a generating line segment of a cylinder) of the rolling object is zero. In practice, due to small deformations near the contact area, some sliding and energy dissipation occurs. Nevertheless, the resulting rolling resistance is much lower than sliding friction, and thus, roll ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sparassidae
Huntsman spiders, members of the family Sparassidae (formerly Heteropodidae), are known by this name because of their speed and mode of hunting. They are also called giant crab spiders because of their size and appearance. Larger species sometimes are referred to as wood spiders, because of their preference for woody places (forests, mine shafts, woodpiles, wooden shacks). In southern Africa the genus ''Palystes'' are known as rain spiders or lizard-eating spiders. Commonly, they are confused with baboon spiders from the Mygalomorphae infraorder, which are not closely related. More than a thousand Sparassidae species occur in most warm temperate to tropical regions of the world, including much of Australasia, Africa, Asia, the Mediterranean Basin, and the Americas. Several species of huntsman spider can use an unusual form of locomotion. The wheel spider (''Carparachne aureoflava'') from the Namib uses a cartwheeling motion which gives it its name, while ''Cebrennus rechenbergi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
