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Ecological Genetics
Ecological genetics is the study of genetics in natural populations. It combines ecology, evolution, and genetics to understand the processes behind adaptation. It is virtually synonymous with the field of molecular ecology. This contrasts with classical genetics, which works mostly on crosses between laboratory strains, and DNA sequence analysis, which studies genes at the molecular level. Research in this field is on traits of ecological significance—traits that affect an organism's fitness, or its ability to survive and reproduce. Examples of such traits include flowering time, drought tolerance, polymorphism, mimicry, and avoidance of attacks by predators.Ruxton G.D. Sherratt T.N. and Speed M.P. 2004. ''Avoiding attack: the evolutionary ecology of crypsis, warning signals & mimicry''. Oxford University Press. Research usually involves a mixture of field and laboratory studies. Samples of natural populations may be taken back to the laboratory for their genetic varia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetics
Genetics is the study of genes, genetic variation, and heredity in organisms.Hartl D, Jones E (2005) It is an important branch in biology because heredity is vital to organisms' evolution. Gregor Mendel, a Moravian Augustinians, Augustinian friar working in the 19th century in Brno, was the first to study genetics scientifically. Mendel studied "trait inheritance", patterns in the way traits are handed down from parents to offspring over time. He observed that organisms (pea plants) inherit traits by way of discrete "units of inheritance". This term, still used today, is a somewhat ambiguous definition of what is referred to as a gene. Phenotypic trait, Trait inheritance and Molecular genetics, molecular inheritance mechanisms of genes are still primary principles of genetics in the 21st century, but modern genetics has expanded to study the function and behavior of genes. Gene structure and function, variation, and distribution are studied within the context of the Cell (bi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Modern Synthesis (20th Century)
The modern synthesis was the early 20th-century synthesis of Charles Darwin's theory of evolution and Gregor Mendel's ideas on Mendelian inheritance, heredity into a joint mathematical framework. Julian Huxley coined the term in his 1942 book, ''Evolution: The Modern Synthesis''. The synthesis combined the ideas of natural selection, Mendelian inheritance, Mendelian genetics, and population genetics. It also related the broad-scale macroevolution seen by paleontology, palaeontologists to the small-scale microevolution of local population, populations. The synthesis was defined differently by its founders, with Ernst Mayr in 1959, G. Ledyard Stebbins in 1966, and Theodosius Dobzhansky in 1974 offering differing basic postulates, though they all include natural selection, working on heritable variation supplied by mutation. Other major figures in the synthesis included E. B. Ford, Bernhard Rensch, Ivan Schmalhausen, and George Gaylord Simpson. An early event in the modern synthesi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heliconius Mimicry
''Heliconius'' comprises a colorful and widespread genus of brush-footed butterflies commonly known as the longwings or heliconians. This genus is distributed throughout the tropical and subtropical regions of the New World, from South America as far north as the southern United States. The larvae of these butterflies eat passion flower vines (Passifloraceae). Adults exhibit bright wing color patterns which signal their distastefulness to potential predators. Brought to the forefront of scientific attention by Victorian naturalists, these butterflies exhibit a striking diversity and mimicry, both amongst themselves and with species in other groups of butterflies and moths. The study of ''Heliconius'' and other groups of mimetic butterflies allowed the English naturalist Henry Walter Bates, following his return from Brazil in 1859, to lend support to Charles Darwin, who had found similar diversity amongst the Galápagos finches. Model for evolutionary study ''Heliconius'' b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 Sulfur dioxide, sulphur dioxide gas and dark soot deposits. Sulphur dioxide kills lichens, leaving tree Bark (botany), 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 (1907–1979), is a popular Teaching of evolution, teaching example in Darwinian evolution, providing Coloration evidence for natural selection, 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lichte En Zwarte Versie Berkenspanner
image:Wallendorfer Porzellan Manufaktur.jpg, 220px, Wallendorfer Porcelain Manufacture, Oct. 2006 image:Talsperre Leibis Lichte in August 2009.jpg, 220px, Leibis-Lichte Dam, 102.5 m high Lichte is a village and a former municipality in the Sonneberg (district), district of Sonneberg in Thuringia, Germany, close to the Rennsteig, Thuringian Rennsteig. Formerly in the district Saalfeld-Rudolstadt, it is part of the town Neuhaus am Rennweg since January 2019. Geography Lichte is located between the towns of Saalfeld (to the north), Oberhof, Germany, Oberhof / Ilmenau (northwest) and Sonneberg / Coburg (south) at an altitude of 600 m Normalhöhennull, (NHN), in the centre of the Thuringian Highlands / Thuringian Forest Nature Park. Distinctive sign of Lichte is the railway viaduct established in 1909 (see picture right). It is a typical Thuringian Forest village, reaching far into the valleys of the Lichte (River), Lichte River and of its tributary the Piesau (river), Piesau. Bot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural Selection
Natural selection is the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in the Heredity, heritable traits characteristic of a population over generations. Charles Darwin popularised the term "natural selection", contrasting it with selective breeding, artificial selection, which is intentional, whereas natural selection is not. Genetic diversity, Variation of traits, both Genotype, genotypic and phenotypic, exists within all populations of organisms. However, some traits are more likely to facilitate survival and reproductive success. Thus, these traits are passed the next generation. These traits can also become more Allele frequency, common within a population if the environment that favours these traits remains fixed. If new traits become more favoured due to changes in a specific Ecological niche, niche, microevolution occurs. If new traits become more favoured due to changes in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blood Groups
The term human blood group systems is defined by the International Society of Blood Transfusion (ISBT) as systems in the human species where cell-surface antigens—in particular, those on blood cells—are "controlled at a single gene locus or by two or more very closely linked homologous genes with little or no observable recombination between them", and include the common ABO and Rh (Rhesus) antigen systems, as well as many others; 47 human systems are identified . Table of systems and classifications Antibodies Following is a comparison of clinically relevant characteristics of antibodies against the main human blood group systems: Compatibility testing Blood compatibility testing is performed before blood transfusion, including matching of the ABO blood group system and the Rh blood group system, as well as screening for recipient antibodies against other human blood group systems. Blood compatibility testing is also routinely performed on pregnant women and on th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lepidoptera
Lepidoptera ( ) or lepidopterans is an order (biology), order of winged insects which includes butterflies and moths. About 180,000 species of the Lepidoptera have been described, representing 10% of the total described species of living organisms, making it the second largest insect order (behind Coleoptera) with 126 family (biology), families and 46 Taxonomic rank, superfamilies, and one of the most widespread and widely recognizable insect orders in the world. Lepidopteran species are characterized by more than three derived features. The most apparent is the presence of scale (anatomy), scales that cover the torso, bodies, large triangular Insect wing, wings, and a proboscis for siphoning nectars. The scales are modified, flattened "hairs", and give butterflies and moths their wide variety of colors and patterns. Almost all species have some form of membranous wings, except for a few that have reduced wings or are wingless. Mating and the laying of eggs is normally performe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bernard Kettlewell
Henry Bernard Davis Kettlewell (24 February 1907 – 11 May 1979) was a British geneticist, lepidopterist and medical doctor, who performed research on the influence of industrial melanism on peppered moth (''Biston betularia'') coloration, showing why moths are darker in polluted areas. This experiment is cited as a classic demonstration of natural selection in action. After live video record of the experiment with Niko Tinbergen, Sewall Wright called the study as "the clearest case in which a conspicuous evolutionary process has actually been observed." Early life Kettlewell was born in Howden, Yorkshire, and educated at Charterhouse School. During 1926 he studied medicine and zoology at Gonville and Caius College, Cambridge. During 1929 he began clinical training at St Bartholomew's Hospital, London, then during 1935 joined a general medical practice in Cranleigh, Surrey. He also worked as an anaesthetist at St. Luke's Hospital, Guildford. During World War II, from 1939 to 19 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyril Clarke
Sir Cyril Astley Clarke (22 August 1907 – 21 November 2000) was a British physician, geneticist and lepidopterist. He was honoured for his pioneering work on prevention of Rh disease of the newborn, and also for his work on the genetics of the Lepidoptera (butterflies and moths). Biography Cyril Clarke was born on 22 August 1907 in Leicester, England and received his school education at Wyggeston Grammar School for Boys, Leicester and at the independent Oundle School near Peterborough. His interest in butterflies and moths began at school. His studied natural science at Gonville and Caius College, Cambridge, graduating in 1929, and then medicine at Guy's Hospital, London, graduating in 1932. During the Second World War he worked as a medical specialist in the Royal Naval Volunteer Reserve. After the war Clarke worked as a registrar at the Queen Elizabeth Hospital in Birmingham and then as Consultant Physician at the United Liverpool Hospitals. In 1963 he was appointed Director ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Philip Sheppard (biologist)
Professor Philip MacDonald Sheppard, F.R.S. (27 July 1921 – 17 October 1976) was a British geneticist and lepidopterist. He made advances in ecological and population genetics in lepidopterans, pulmonate land snails and humans. In medical genetics, he worked with Cyril Clarke on Rh disease. He was born on 27 July 1921 in Marlborough, Wiltshire, England and attended Marlborough College from 1935 to 1939. *1940 to 1945 - Royal Air Force Volunteer Reserve (prisoner-of-war from 1942 to 1945). Participated, as an earth-bearer, in one of the famous tunnel escapes; it is unclear whether this was the "Wooden Horse" escape, or the "Great" EscapeDictionary of Scientific Biography vol 17, supplement 2 pp 814–816 *1946 to 1948 - Studied Zoology at Worcester College, University of Oxford. *1956 to 1959 - Lecturer at Liverpool University *1959 to 1962 - Reader at Liverpool University *1963 to 1976 - Professor of genetics at Liverpool University *18 March 1965 - FRS *1974 - Darwin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drosophila
''Drosophila'' (), from Ancient Greek δρόσος (''drósos''), meaning "dew", and φίλος (''phílos''), meaning "loving", is a genus of fly, belonging to the family Drosophilidae, whose members are often called "small fruit flies" or pomace flies, vinegar flies, or wine flies, a reference to the characteristic of many species to linger around overripe or rotting fruit. They should not be confused with the Tephritidae, a related family, which are also called fruit flies (sometimes referred to as "true fruit flies"); tephritids feed primarily on unripe or ripe fruit, with many species being regarded as destructive agricultural pests, especially the Mediterranean fruit fly. One species of ''Drosophila'' in particular, ''Drosophila melanogaster'', has been heavily used in research in genetics and is a common model organism in developmental biology. The terms "fruit fly" and "''Drosophila''" are often used synonymously with ''D. melanogaster'' in modern biological literatur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
