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Trichoniscus Pusillus
''Trichoniscus pusillus'', sometimes called the common pygmy woodlouse, is one of the five most common species of woodlice in the British Isles. It is acknowledged to be the most abundant terrestrial isopod in Britain. It is found commonly across Europe north of the Alps, and has been introduced to Madeira, the Azores and North America. Description ''T. pusillus'' may be distinguished from other British woodlice chiefly by its small size, which reaches no more than . Its body is elongate and quite rounded in cross section, and typically purplish. It may be separated from related species in North America by its eyes of three ocelli each, rather than the single ocellus in the eyes of its relative '' Hyloniscus riparius''. Reproduction There are two distinct reproductive strategies within the species ''Trichoniscus pusillus''. Many populations are, like most metazoans, bisexual and reproduce sexually; in other cases, females reproduce parthenogenetically, creating clones of themsel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johann Friedrich Von Brandt
Johann Friedrich von Brandt (25 May 1802 – 15 July 1879) was a German-Russian natural history, naturalist, who worked mostly in Russia. Brandt was born in Jüterbog and educated at a Gymnasium (school), gymnasium in Wittenberg and the Humboldt University of Berlin, University of Berlin. In 1831 he emigrated to Russia, and soon was appointed director of the Zoological Museum of the St Petersburg Academy of Sciences. Brandt encouraged the collection of native animals, many of which were not represented in the museum. Many specimens began to arrive from the expeditions of Nikolai Alekseevich Severtzov, Severtzov, Nikolai Przhevalsky, Przhevalsky, Aleksandr Fyodorovich Middendorf, Middendorff, Leopold von Schrenck, Schrenck and Gustav Radde. He described several birds collected by Russian explorers off the Pacific Coast of North America, including Brandt's cormorant, red-legged kittiwake and spectacled eider. As a paleontologist, Brandt ranks among the best. He was also an entomo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Encyclopaedia Tiscali
An encyclopedia (American English) or encyclopædia ( British English) is a reference work or compendium providing summaries of knowledge either general or special to a particular field or discipline. Encyclopedias are divided into articles or entries that are arranged alphabetically by article name or by thematic categories, or else are hyperlinked and searchable. Encyclopedia entries are longer and more detailed than those in most dictionaries. Generally speaking, encyclopedia articles focus on ''factual information'' concerning the subject named in the article's title; this is unlike dictionary entries, which focus on linguistic information about words, such as their etymology, meaning, pronunciation, use, and grammatical forms.Béjoint, Henri (2000)''Modern Lexicography'', pp. 30–31. Oxford University Press. Encyclopedias have existed for around 2,000 years and have evolved considerably during that time as regards language (written in a major international or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iberian Peninsula
The Iberian Peninsula (), ** * Aragonese and Occitan: ''Peninsula Iberica'' ** ** * french: Péninsule Ibérique * mwl, Península Eibérica * eu, Iberiar penintsula also known as Iberia, is a peninsula in southwestern Europe, defining the westernmost edge of Eurasia. It is principally divided between Spain and Portugal, comprising most of their territory, as well as a small area of Southern France, Andorra, and Gibraltar. With an area of approximately , and a population of roughly 53 million, it is the second largest European peninsula by area, after the Scandinavian Peninsula. Name Greek name The word ''Iberia'' is a noun adapted from the Latin word "Hiberia" originating in the Ancient Greek word Ἰβηρία ('), used by Greek geographers under the rule of the Roman Empire to refer to what is known today in English as the Iberian Peninsula. At that time, the name did not describe a single geographical entity or a distinct population; the same name was us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scandinavia
Scandinavia; Sámi languages: /. ( ) is a subregion#Europe, subregion in Northern Europe, with strong historical, cultural, and linguistic ties between its constituent peoples. In English usage, ''Scandinavia'' most commonly refers to Denmark, Norway, and Sweden. It can sometimes also refer more narrowly to the Scandinavian Peninsula (which excludes Denmark but includes part of Finland), or more broadly to include all of Finland, Iceland, and the Faroe Islands. The geography of the region is varied, from the Norwegian fjords in the west and Scandinavian mountains covering parts of Norway and Sweden, to the low and flat areas of Denmark in the south, as well as archipelagos and lakes in the east. Most of the population in the region live in the more temperate southern regions, with the northern parts having long, cold, winters. The region became notable during the Viking Age, when Scandinavian peoples participated in large scale raiding, conquest, colonization and trading mostl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scotland
Scotland (, ) is a country that is part of the United Kingdom. Covering the northern third of the island of Great Britain, mainland Scotland has a border with England to the southeast and is otherwise surrounded by the Atlantic Ocean to the north and west, the North Sea to the northeast and east, and the Irish Sea to the south. It also contains more than 790 islands, principally in the archipelagos of the Hebrides and the Northern Isles. Most of the population, including the capital Edinburgh, is concentrated in the Central Belt—the plain between the Scottish Highlands and the Southern Uplands—in the Scottish Lowlands. Scotland is divided into 32 administrative subdivisions or local authorities, known as council areas. Glasgow City is the largest council area in terms of population, with Highland being the largest in terms of area. Limited self-governing power, covering matters such as education, social services and roads and transportation, is devolved from the Scott ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cline (biology)
In biology, a cline (from the Greek κλίνειν ''klinein'', meaning "to lean") is a measurable gradient in a single character (or biological trait) of a species across its geographical range. First coined by Julian Huxley in 1938, the "character" of the cline referred to is usually genetic (e.g. allele frequency, blood type), or phenotypic (e.g. body size, skin pigmentation). Clines can show smooth, continuous gradation in a character, or they may show more abrupt changes in the trait from one geographic region to the next. A cline refers to a spatial gradient in a specific, singular trait, rather than a collection of traits; a single population can therefore have as many clines as it has traits, at least in principle. Additionally, Huxley recognised that these multiple independent clines may not act in concordance with each other. For example, it has been observed that in Australia, birds generally become smaller the further towards the north of the country they are found ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triploid
Polyploidy is a condition in which the cells of an organism have more than one pair of ( homologous) chromosomes. Most species whose cells have nuclei ( eukaryotes) are diploid, meaning they have two sets of chromosomes, where each set contains one or more chromosomes and comes from each of two parents, resulting in pairs of homologous chromosomes between sets. However, some organisms are polyploid. Polyploidy is especially common in plants. Most eukaryotes have diploid somatic cells, but produce haploid gametes (eggs and sperm) by meiosis. A monoploid has only one set of chromosomes, and the term is usually only applied to cells or organisms that are normally diploid. Males of bees and other Hymenoptera, for example, are monoploid. Unlike animals, plants and multicellular algae have life cycles with two alternating multicellular generations. The gametophyte generation is haploid, and produces gametes by mitosis, the sporophyte generation is diploid and produces spores by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diploid
Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Sets of chromosomes refer to the number of maternal and paternal chromosome copies, respectively, in each homologous chromosome pair, which chromosomes naturally exist as. Somatic cells, tissues, and individual organisms can be described according to the number of sets of chromosomes present (the "ploidy level"): monoploid (1 set), diploid (2 sets), triploid (3 sets), tetraploid (4 sets), pentaploid (5 sets), hexaploid (6 sets), heptaploid or septaploid (7 sets), etc. The generic term polyploid is often used to describe cells with three or more chromosome sets. Virtually all sexually reproducing organisms are made up of somatic cells that are diploid or greater, but ploidy level may vary widely between different organisms, between different tissues within the same organism, and at different stages in an organism's life cycle. Half ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hereditas
''Hereditas'' (not to be confused with another journal called ''Heredity'') is a scientific journal concerning genetics. It has been published since 1920 by Mendelska sällskapet i Lund (Mendelian Society of Lund). In its long history it has published important papers in the field of genetics, including the first discovery of the correct human chromosome count by Joe Hin Tijo and Albert Levan in 1956. In the post-genomic era, the scope of ''Hereditas'' has evolved to include any research on genomic analysis. In 2005, ''Hereditas'' changed from a traditional subscription-based journal to become an open access, web based and author funded journal. By the end of 2014, Hereditas terminated its activity with Wiley Publishers. In May 2015 ''Hereditas'' was re-launched and became part of the portfolio of the open access publisher Biomed Central (BMC), now owned by Springer Nature Springer Nature or the Springer Nature Group is a German-British academic publishing company created by th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parthenogenesis
Parthenogenesis (; from the Greek grc, παρθένος, translit=parthénos, lit=virgin, label=none + grc, γένεσις, translit=génesis, lit=creation, label=none) is a natural form of asexual reproduction in which growth and development of embryos occur in a gamete (egg or sperm) without combining with another gamete (e.g., egg and sperm fusing). In animals, parthenogenesis means development of an embryo from an unfertilized Gametophyte, egg cell. In plants, parthenogenesis is a component process of apomixis. In algae, parthenogenesis can mean the development of an embryo from either an individual sperm or an individual egg. Parthenogenesis occurs naturally in some plants, algae, invertebrate animal species (including nematodes, some tardigrades, water fleas, some scorpions, aphids, some mites, some bees, some Phasmatodea and parasitic wasps) and a few vertebrates (such as some fish, amphibians, reptiles and birds). This type of reproduction has been induced artificially ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sexual Reproduction
Sexual reproduction is a type of reproduction that involves a complex life cycle in which a gamete ( haploid reproductive cells, such as a sperm or egg cell) with a single set of chromosomes combines with another gamete to produce a zygote that develops into an organism composed of cells with two sets of chromosomes ( diploid). This is typical in animals, though the number of chromosome sets and how that number changes in sexual reproduction varies, especially among plants, fungi, and other eukaryotes. Sexual reproduction is the most common life cycle in multicellular eukaryotes, such as animals, fungi and plants. Sexual reproduction also occurs in some unicellular eukaryotes. Sexual reproduction does not occur in prokaryotes, unicellular organisms without cell nuclei, such bacteria and archaea. However, some process in bacteria may be considered analogous to sexual reproduction in that they incorporate new genetic information, including bacterial conjugation, transformatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metazoa
Animals are multicellular, eukaryotic organisms in the biological kingdom Animalia. With few exceptions, animals consume organic material, breathe oxygen, are able to move, can reproduce sexually, and go through an ontogenetic stage in which their body consists of a hollow sphere of cells, the blastula, during embryonic development. Over 1.5 million living animal species have been described—of which around 1 million are insects—but it has been estimated there are over 7 million animal species in total. Animals range in length from to . They have complex interactions with each other and their environments, forming intricate food webs. The scientific study of animals is known as zoology. Most living animal species are in Bilateria, a clade whose members have a bilaterally symmetric body plan. The Bilateria include the protostomes, containing animals such as nematodes, arthropods, flatworms, annelids and molluscs, and the deuterostomes, containing the echinoderms an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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