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Ecological Genetics
Ecological genetics is the study of genetics in natural populations. Traits in a population can be observed and quantified to represent a species adapting to a changing environment. 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—that is, traits related to fitness, which affect an organism's survival and reproduction. Examples might be: flowering time, drought tolerance, polymorphism, mimicry, and avoidance of attacks by predators. Ecological genetics is an especially useful tool when studying endangered species. Meta-barcoding and eDNA are used to examine the biodiversity of species in an ecosystem. Research usually involves a mixture of field and laboratory studies. Samples of natural populations may be taken back to the laboratory for their genetic variation to be analyzed. Changes in t ... [...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 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. Trait inheritance and 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, the organism (e.g. dominance), and within the ... [...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 heritable traits characteristic of a population over generations. Charles Darwin popularised the term "natural selection", contrasting it with artificial selection, which in his view is intentional, whereas natural selection is not. Variation exists within all populations of organisms. This occurs partly because random mutations arise in the genome of an individual organism, and their offspring can inherit such mutations. Throughout the lives of the individuals, their genomes interact with their environments to cause variations in traits. The environment of a genome includes the molecular biology in the cell, other cells, other individuals, populations, species, as well as the abiotic environment. Because individuals with certain variants of the trait tend to survive and reproduce more than individual ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peppered Moth
The peppered moth (''Biston betularia'') is a temperate species of night-flying moth. It is mostly found in the northern hemisphere in places like Asia, Europe and North America. Peppered moth evolution is an example of population genetics and natural selection. The caterpillars of the peppered moth not only mimic the form but also the colour of a twig. Recent research indicates that the caterpillars can sense the twig's colour with their skin and match their body colour to the background to protect themselves from predators. Description The wingspan ranges from 45 mm to 62 mm (median 55 mm). It is relatively stout-bodied, with forewings relatively narrow-elongate. The wings are white, "peppered" with black, and with more-or-less distinct cross lines, also black. These transverse wing lines and "peppered" maculation (spotting) can also, in rare instances, be gray or brown; the spotting pattern, in particularly very rare cases, is sometimes a combination of b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetic Monitoring
Genetic monitoring is the use of molecular markers to (i) identify individuals, species or populations, or (ii) to quantify changes in population genetic metrics (such as effective population size, genetic diversity and population size) over time. Genetic monitoring can thus be used to detect changes in species abundance and/or diversity, and has become an important tool in both conservation and livestock management. The types of molecular markers used to monitor populations are most commonly mitochondrial, microsatellites or single-nucleotide polymorphisms (SNPs), while earlier studies also used allozyme data. Species gene diversity is also recognized as an important biodiversity metric for implementation of the Convention on Biological Diversity. Types Types of population changes that can be detected by genetic monitoring include population growth and decline, spread of pathogens, adaptation to environmental change, hybridization, introgression and habitat fragmentation events. Mos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetic Ecology
Genetic ecology is the study of the stability and expression of varying genetic material within abiotic mediums. Typically, genetic data is not thought of outside of any organism save for criminal forensics. However, genetic material has the ability to be taken up by various organisms that exist within an abiotic medium through natural transformations that may occur. Thus, this field of study focuses on interaction, exchange, and expression of genetic material that may not be shared by species had they not been in the same environment. History E.B. Ford was the first geneticist to begin work in this field of study. E.B. Ford worked mostly during the 1950s and is most noted for his work with ''Maniola jurtina'' and published a book entitled ''Ecological Genetics'' in 1975. This type of evolutionary biological study was only possible after gel electrophoresis had been designed in 1937. Prior to this, a high throughput method for DNA analysis did not exist. This field of study began t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antibiotic Resistance
Antimicrobial resistance (AMR) occurs when microbes evolve mechanisms that protect them from the effects of antimicrobials. All classes of microbes can evolve resistance. Fungi evolve antifungal resistance. Viruses evolve antiviral resistance. Protozoa evolve antiprotozoal resistance, and bacteria evolve antibiotic resistance. Those bacteria that are considered extensively drug resistant (XDR) or totally drug-resistant (TDR) are sometimes called "superbugs".A.-P. Magiorakos, A. Srinivasan, R. B. Carey, Y. Carmeli, M. E. Falagas, C. G. Giske, S. Harbarth, J. F. Hinndler ''et al''Multidrug-resistant, extensively drug-resistant and pandrug-resistant bacteria... Clinical Microbiology and Infection, Vol 8, Iss. 3 first published 27 July 2011 ia Wiley Online Library Retrieved 28 August 2020 Although antimicrobial resistance is a naturally-occurring process, it is often the result of improper usage of the drugs and management of the infections. Antibiotic resistance is a major subset ... [...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; 43 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 ( ) is an order of insects that includes butterflies and moths (both are called lepidopterans). About 180,000 species of the Lepidoptera are described, in 126 families and 46 superfamilies, 10 percent of the total described species of living organisms. It is one of the most widespread and widely recognizable insect orders in the world. The Lepidoptera show many variations of the basic body structure that have evolved to gain advantages in lifestyle and distribution. Recent estimates suggest the order may have more species than earlier thought, and is among the four most speciose orders, along with the Hymenoptera, Diptera, and Coleoptera. Lepidopteran species are characterized by more than three derived features. The most apparent is the presence of scales that cover the bodies, wings, and a proboscis. 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 mem ... [...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 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyril Clarke
Sir Cyril Astley Clarke, KBE, FRCP, FRCOG, (Hon) FRC Path, FRS (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 Ho ... [...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 Sir 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 - Darw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sergei Chetverikov
Sergei Sergeevich Chetverikov (russian: Серге́й Серге́евич Четверико́в; 6 May 1880 – 2 July 1959) was a Russian biologist and one of the early contributors to the development of the field of genetics. His research showed how early genetic theories applied to natural populations, and has therefore contributed towards the modern synthesis of evolutionary theory. Between the two World Wars, Soviet biological research managed to connect genetics with field research on natural populations. Chetverikov lead a team at the Nikolai Koltsov Institute of Experimental Biology in Moscow, and in 1926 produced what should have been one of the landmark papers of the modern synthesis. However, published only in Russian, it was largely ignored in the English-speaking world (though J.B.S. Haldane possessed a translation). Chetverikov influenced several Russian geneticists who later came to work in the West, such as Theodosius Dobzhansky and Nikolay Timofeev-Ressovsk ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
