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Industrial Melanism
Industrial melanism is an evolutionary effect prominent in several arthropods, where dark pigmentation (melanism) has evolved in an environment affected by industrial pollution, including sulphur dioxide gas and dark soot deposits. Sulphur dioxide kills lichens, leaving tree bark bare where in clean areas it is boldly patterned, while soot darkens bark and other surfaces. Darker pigmented individuals have a higher fitness in those areas as their camouflage matches the polluted background better; they are thus favoured by natural selection. This change, extensively studied by Bernard Kettlewell, is a popular teaching example in Darwinian evolution, providing evidence for natural selection. Kettlewell's results have been challenged by zoologists, creationists and the journalist Judith Hooper, but later researchers have upheld Kettlewell's findings. Industrial melanism is widespread in the Lepidoptera (butterflies and moths), involving over 70 species such as ''Odontopera bide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Odontopera Bidentata
The scalloped hazel (''Odontopera bidentata'') is a moth of the family Geometridae. The species was first described by Carl Alexander Clerck in 1759. Distribution It is a common species of northern and central Europe including the British Isles and Russia to the Urals. It is also widespread through Siberia and the Amur-Ussuri region to the Kuril Islands and Japan. Description The wingspan is 46–50 mm. The forewing ground colour is usually grey brown. The same coloured midfield is bordered by blackish crossbars that are often partly white. At the wing edge below the apex are two characteristic, protruding teeth. The scientific name of the species is derived from the Latin language ''bi'' = "twice" and ''dentatus'' = "toothed". The outer dark crossline of the forewings continues on the hindwings. All wings have a ring-shaped dark discal spots. The thorax is hairy. This is a very variable species with the wing colour ranging from whitish through buff and brown to black, s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lymantria Monacha
The black arches or nun moth (''Lymantria monacha'')Carter, David. Butterflies and Moths, Dorling Kindersley, pg 271 is a small Palaearctic moth. It is considered a forest pest. Description The moths of ''Lymantria monacha'' have a wingspan of 40 to 50 mm. They have white forewings with black connected wavy arches which gives the moth its name. The light brown hindwings have white fringes having black spots. They also have a characteristic biscuit-coloured abdomen with a black band. Females are larger and have elongated wings. The eggs are oval, light brown or light red. Larvae are whitish grey to blackish, with grey hairs, red and blue warts, and a dark longitudinal dorsal line which is interrupted or broadened into spots in places. Pupa is golden glossy red-brown or dark brown, with reddish hairs dorsally and rather long anal point. Technical description and variation White forewing with black basal spots and four sharply angulate black transverse lines, the second of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kettlewell's Experiment
Kettlewell's experiment was a biological experiment in the mid-1950s to study the evolutionary mechanism of industrial melanism in the peppered moth (''Biston betularia''). It was executed by Bernard Kettlewell, working as a research fellow in the Department of Zoology, University of Oxford. He was investigating the cause of the appearance of dark-coloured moth since Industrial Revolution in England in the 19th century. He conducted his first experiment in 1953 in the polluted woodland of Birmingham, and his second experiment in 1955 in Birmingham as well as in the clean woods of Dorset. The experiment found that birds selectively prey on peppered moths depending on their body colour in relation to their environmental background. Thus, the evolution of a dark-coloured body provided a survival advantage in a polluted locality. The study concluded that "industrial melanism in moths is the most striking evolutionary phenomenon ever actually witnessed in any organism, animal or plant. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mathematical Model
A mathematical model is a description of a system using mathematical concepts and language. The process of developing a mathematical model is termed mathematical modeling. Mathematical models are used in the natural sciences (such as physics, biology, earth science, chemistry) and engineering disciplines (such as computer science, electrical engineering), as well as in non-physical systems such as the social sciences (such as economics, psychology, sociology, political science). The use of mathematical models to solve problems in business or military operations is a large part of the field of operations research. Mathematical models are also used in music, linguistics, and philosophy (for example, intensively in analytic philosophy). A model may help to explain a system and to study the effects of different components, and to make predictions about behavior. Elements of a mathematical model Mathematical models can take many forms, including dynamical systems, statisti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leonard Doncaster
Leonard Doncaster (31 December 1877 – 28 May 1920) was an English geneticist and a lecturer on zoology at both Birmingham University and the University of Liverpool whose research work was largely based on insects. Early life Doncaster was born on 31 December 1877 in Abbeydale, Sheffield.His father was Samuel Doncaster, an iron merchant, of Abbeydale, Sheffield, Yorkshire. Career After education at Leighton Park School in Reading South England he studied at King's College, Cambridge, from 1896 onward. He was Scholar of natural sciences in 1898, and Walsingham Medallist in 1902. In June 1902 he was appointed assistant to the Superintendent of the Cambridge University Museum of Zoology, From 1906-10 he was a Lecturer in Zoology at Birmingham University. He was an early Mendelian geneticist who discovered sex linkage, while writing up breeding experiment results of the Reverend G.H. Raynor on the magpie moth ''Abraxas grossulariata'' published in 1906. He wrote a number of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymorphism (biology)
In biology, polymorphism is the occurrence of two or more clearly different morphs or forms, also referred to as alternative ''phenotypes'', in the population of a species. To be classified as such, morphs must occupy the same habitat at the same time and belong to a panmictic population (one with random mating). Ford E.B. 1965. ''Genetic polymorphism''. Faber & Faber, London. Put simply, polymorphism is when there are two or more possibilities of a trait on a gene. For example, there is more than one possible trait in terms of a jaguar's skin colouring; they can be light morph or dark morph. Due to having more than one possible variation for this gene, it is termed 'polymorphism'. However, if the jaguar has only one possible trait for that gene, it would be termed "monomorphic". For example, if there was only one possible skin colour that a jaguar could have, it would be termed monomorphic. The term polyphenism can be used to clarify that the different forms arise from the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Bateson
William Bateson (8 August 1861 – 8 February 1926) was an English biologist who was the first person to use the term genetics to describe the study of heredity, and the chief populariser of the ideas of Gregor Mendel following their rediscovery in 1900 by Hugo de Vries and Carl Correns. His 1894 book ''Materials for the Study of Variation'' was one of the earliest formulations of the new approach to genetics. Early life and education Bateson was born 1861 in Whitby on the Yorkshire coast, the son of William Henry Bateson, Master of St John's College, Cambridge. He was educated at Rugby School and at St John's College, where he graduated BA in 1883 with a first in natural sciences. Taking up embryology, he went to the United States to investigate the development of ''Balanoglossus'', a worm-like hemichordate which led to his interest in vertebrate origins. In 1883–4 he worked in the laboratory of William Keith Brooks, at the Chesapeake Zoölogical Laboratory in Hampton, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biston Betularia 20110529 102239 8073M
In Greek mythology, Biston (Ancient Greek: Βίστων or Βιστών) was the son of Ares and Callirrhoe, daughter of river-god Nestus. His two brothers were Odomas and Edonus (eponyms of two Thracian tribes, the Odomanti and the Edoni). Alternately, he was called son of Paeon and grandson of Ares. In some accounts, he was the son of either the Muses Terpsichorus''Etymologicum Magnum'', 197. 59 s. v. ''Bistoniē'' or Calliope. Mythology Biston built the city of Bistonia on the shores of Lake Bistonis in Thrace. He also introduced the Thracian practice of tattooing both men and women with eye-like patterns as a magical fetish, in response to an oracle which guaranteed victory against the neighbouring Edonians tribe if so adorned. The Thracian Bistonians were famous for their warlike nature and cult of Ares whom they worshipped in the form of an upright standing sword. See also * Bistones * Bistonis, the nymph who lives at Lake Bistonis. Notes Reference * Stephanus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural Experiment
A natural experiment is an empirical study in which individuals (or clusters of individuals) are exposed to the experimental and control conditions that are determined by nature or by other factors outside the control of the investigators. The process governing the exposures arguably resembles random assignment. Thus, natural experiments are ''observational studies'' and are not controlled in the traditional sense of a randomized experiment (an ''intervention study''). Natural experiments are most useful when there has been a clearly defined exposure involving a well defined subpopulation (and the absence of exposure in a similar subpopulation) such that changes in outcomes may be plausibly attributed to the exposure. In this sense, the difference between a natural experiment and a non-experimental observational study is that the former includes a comparison of conditions that pave the way for causal inference, but the latter does not. Natural experiments are employed as study des ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sloughing
In biology, moulting (British English), or molting (American English), also known as sloughing, shedding, or in many invertebrates, ecdysis, is the manner in which an animal routinely casts off a part of its body (often, but not always, an outer layer or covering), either at specific times of the year, or at specific points in its life cycle. In medieval times it was also known as "mewing" (from the French verb "muer", to moult), a term that lives on in the name of Britain's Royal Mews where the King's hawks used to be kept during moulting time before becoming horse stables after Tudor times. Moulting can involve shedding the epidermis (skin), pelage (hair, feathers, fur, wool), or other external layer. In some groups, other body parts may be shed, for example, the entire exoskeleton in arthropods, including the wings in some insects. Examples In birds In birds, moulting is the periodic replacement of feathers by shedding old feathers while producing new ones. Feathers are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emydocephalus Annulatus
''Emydocephalus annulatus'', commonly known as the turtleheaded sea snake or egg-eating sea snake, is a species of sea snake that can be found in waters of Oceania near Australia and some Pacific Islands such as the Philippines and the Loyalty Islands of New Caledonia. The geographic range is sporadic, for example, with populations distributed near the eastern and western coasts of Australia in the Great Barrier Reef and the Timor Sea reefs, respectively. They do not, however, occur in the Gulf of Carpentaria along the north coast.''Emydocephalus annulatus'' (2010). ''The IUCN Red List of Threatened Species''. International Union for Conservation of Nature. Description Named for its short, blunt head, this medium-sized snake has a slender build and varies in color. A single snake may exhibit only one color ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aposematism
Aposematism is the advertising by an animal to potential predators that it is not worth attacking or eating. This unprofitability may consist of any defences which make the prey difficult to kill and eat, such as toxicity, venom, foul taste or smell, sharp spines, or aggressive nature. These advertising signals may take the form of conspicuous coloration, sounds, odours, or other perceivable characteristics. Aposematic signals are beneficial for both predator and prey, since both avoid potential harm. The term was coined in 1877 by Edward Bagnall Poulton for Alfred Russel Wallace's concept of warning coloration. Aposematism is exploited in Müllerian mimicry, where species with strong defences evolve to resemble one another. By mimicking similarly coloured species, the warning signal to predators is shared, causing them to learn more quickly at less of a cost. A genuine aposematic signal that a species actually possesses chemical or physical defences is not the only way to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
