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Panmictic
Panmixia (or panmixis) means random mating. A panmictic population is one where all individuals are potential partners. This assumes that there are no mating restrictions, neither genetic nor behavioural, upon the population and that therefore all recombination is possible. The Wahlund effect assumes that the overall population is panmictic. In genetics, random mating involves the mating of individuals regardless of any physical, genetic or social preference. In other words, the mating between two organisms is not influenced by any environmental, hereditary or social interaction. Hence, potential mates have an equal chance of being selected. Random mating is a factor assumed in the Hardy–Weinberg principle and is distinct from lack of natural selection: in viability selection for instance, selection occurs ''before'' mating. Description In simple terms, panmixia (or panmicticism) is the ability of individuals in a population to interbreed without restrictions; individuals are ab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monostroma
''Monostroma'' is a genus of marine green algae (seaweed) in the family Monostromataceae. As the name suggests, algae of this genus are monostromatic (single cell layered). ''Monostroma kuroshiense'', an algae of this genus, is commercially cultivated in East Asia and South America for the edible product "hitoegusa-nori" or "hirohano-hitoegusa nori", popular sushi wraps. ''Monostroma'' oligosaccharides with degree of polymerization 6 prepared by agarase digestion from ''Monostroma nitidum'' polysaccharides have been shown to be an effective prophylactic agent during ''in vitro'' and ''in vivo'' tests against Japanese encephalitis viral infection. The sulfated oligosaccharides from ''Monostroma'' seem to be promising candidates for further development as antiviral agents. The genus ''Monostroma'' is the most widely cultivated genus among green seaweeds. Classification Species-level classification within this genus is quite problematic and no consensus exists among algal taxonomist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pantala Flavescens
''Pantala flavescens'', the globe skimmer, globe wanderer or wandering glider, is a wide-ranging dragonfly of the family Libellulidae. This species and ''Pantala hymenaea'', the "spot-winged glider", are the only members of the genus ''Pantala''. It was first described by Johan Christian Fabricius in 1798. It is considered to be the most widespread dragonfly on the planet with good population on every continent except Antarctica although rare in Europe. Globe skimmers make an annual multigenerational journey of some 18,000 km (about 11,200 miles); to complete the migration, individual globe skimmers fly more than 6,000 km (3,730 miles)—one of the farthest known migrations of all insect species. Characteristics Structure of the adult The dragonfly is up to 4.5 cm long, reaching wingspans between 7.2 cm and 8.4 cm. The front side of the head is yellowish to reddish. The thorax is usually yellow to golden coloured with a dark and hairy line. There were a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sympatric Speciation
Sympatric speciation is the evolution of a new species from a surviving ancestral species while both continue to inhabit the same geographic region. In evolutionary biology and biogeography, sympatric and sympatry are terms referring to organisms whose ranges overlap so that they occur together at least in some places. If these organisms are closely related (e.g. sister species), such a distribution may be the result of sympatric speciation. Etymologically, sympatry is derived from the Greek roots ("together") and ("homeland"). The term was coined by Edward Bagnall Poulton in 1904, who explains the derivation. Sympatric speciation is one of three traditional geographic modes of speciation.Futuyma, D. J. 2009. ''Evolution'' (2nd edition). Sinauer Associates, Inc. Allopatric speciation is the evolution of species caused by the geographic isolation of two or more populations of a species. In this case, divergence is facilitated by the absence of gene flow. Parapatric speciation ... [...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] |
Sexual Selection
Sexual selection is a mode of natural selection in which members of one biological sex mate choice, choose mates of the other sex to mating, mate with (intersexual selection), and compete with members of the same sex for access to members of the opposite sex (intrasexual selection). These two forms of selection mean that some individuals have greater reproductive success than others within a population, for example because they are more Animal sexual behaviour, attractive or prefer more attractive partners to produce offspring. Successful males benefit from frequent mating and monopolizing access to one or more fertile females. Females can maximise the return on the energy they invest in reproduction by selecting and mating with the best males. The concept was first articulated by Charles Darwin who wrote of a "second agency" other than natural selection, in which competition between mate candidates could lead to speciation. The theory was given a mathematical basis by Ronald F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monogamy In Animals
Monogamous pairing in animals refers to the natural history of mating systems in which species pair bond to raise offspring. This is associated, usually implicitly, with sexual monogamy. Monogamous mating Monogamy is defined as a pair bond between two adult animals of the same species – typically of the opposite sex. This pair may cohabitate in an area or territory for some duration of time, and in some cases may copulate and reproduce with only each other. Monogamy may either be short-term, lasting one to a few seasons or long-term, lasting many seasons and in extreme cases, life-long. Monogamy can be partitioned into two categories, social monogamy and genetic monogamy which may occur together in some combination, or completely independently of one another.Ophir, Alexander G., Phelps, Steven M., Sorin, Anna Bess & O. Wolff, J. (2008)Social but not genetic monogamy is associated with greater breeding success in prairie voles/ref> As an example, in the cichlid species '' Variab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Population Genetics
Population genetics is a subfield of genetics that deals with genetic differences within and between populations, and is a part of evolutionary biology. Studies in this branch of biology examine such phenomena as adaptation, speciation, and population structure. Population genetics was a vital ingredient in the emergence of the modern evolutionary synthesis. Its primary founders were Sewall Wright, J. B. S. Haldane and Ronald Fisher, who also laid the foundations for the related discipline of quantitative genetics. Traditionally a highly mathematical discipline, modern population genetics encompasses theoretical, laboratory, and field work. Population genetic models are used both for statistical inference from DNA sequence data and for proof/disproof of concept. What sets population genetics apart from newer, more phenotypic approaches to modelling evolution, such as evolutionary game theory and adaptive dynamics, is its emphasis on such genetic phenomena as dominance, epi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Assortative Mating
Assortative mating (also referred to as positive assortative mating or homogamy) is a mating pattern and a form of sexual selection in which individuals with similar phenotypes or genotypes mate with one another more frequently than would be expected under a random mating pattern. A majority of the phenotypes that are subject to assortative mating are body size, visual signals (e.g. color, pattern), and sexually selected traits such as crest size. The opposite of assortative is disassortative mating. Causes Several hypotheses have been proposed to explain the phenomenon of assortative mating. Assortative mating has evolved from a combination of different factors, which vary across different species. Assortative mating with respect to body size can arise as a consequence of intrasexual competition. In some species, size is correlated with fecundity in females. Therefore, males choose to mate with larger females, with the larger males defeating the smaller males in courting the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amegilla Dawsoni
''Amegilla dawsoni'', sometimes called the Dawson's burrowing bee, is a species of bee that nests by the thousands in arid claypans in Western Australia. It is a long tongued bee, of the tribe Anthophorini and genus ''Amegilla,'' the second largest genus in Anthophorini. The Dawson's burrowing bee is one of the largest Australian bee species, growing to be in length and in wingspan. With the exception of their faces, the bees are covered in brown fur, if male, or brown and white fur if female. They are similar in size and coloring to Australian carpenter bees. They are known solitary nesters. Though each female bee will build her own nest, they aggregate in large communities that give the appearance of colonies. Their nests are dug into the ground, with individual capsules created for each brood cell. Each female will only breed once in their breeding season. The males of the species are dimorphic, based on brood provisioning strategies during development. The larger males ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pantala Flavescens-Kadavoor-2017-05-04-002
''Pantala'' is a genus of dragonfly in the family Libellulidae The skimmers or perchers and their relatives form the Libellulidae, the largest dragonfly family in the world. It is sometimes considered to contain the Corduliidae as the subfamily Corduliinae and the Macromiidae as the subfamily Macromiinae. Ev ... commonly called the rainpool gliders. They are found almost worldwide. Species of ''Pantala'' are medium-sized to large, dull orange-yellow dragonflies. Species The genus ''Pantala'' includes the following species: References External links * * {{Taxonbar, from=Q149707 Libellulidae Anisoptera genera Odonata of Africa Odonata of Asia Odonata of Australia Odonata of Oceania Taxa named by Hermann August Hagen Insects described in 1861 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
