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Desert Grassland Whiptail Lizard
The desert grassland whiptail lizard (''Aspidoscelis uniparens'') is an all-female species of reptiles in North America. It was formerly placed in the genus ''Cnemidophorus''. A common predator of the whiptail lizard is the leopard lizard that preys on ''A. uniparens'' by using ambush and stalk hunting tactics. These reptiles reproduce by parthenogenesis. In this process, eggs undergo a chromosome doubling after meiosis, developing into lizards without being fertilized. However, ovulation is enhanced by female-female courtship and mating (pseudo-copulation) rituals that resemble the behavior of closely related species that reproduce sexually. Description The desert grassland whiptail lizard is a relatively small reptile, whose size ranges from . Desert grassland whiptails are very long and slim, with a thin tail that is longer than their body length. Their distinct identifying feature are the six yellowish lines that run the length of their body. The majority of the whiptail's b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charles Herbert Lowe
Charles Herbert Lowe, Jr. (April 16, 1920 – September 13, 2002) was an American biologist and herpetologist. Lowe was born in Los Angeles, California. After college he served during World War II as a U.S. Navy Ensign in the Pacific. In 1946, he enrolled at UCLA, where he received a Ph.D. in 1950. He then went to the University of Arizona in Tucson, Arizona, where he became a professor of ecology and evolutionary biology. His interests focused on the desert fauna, especially of the Sonoran Desert. He did many extensive studies, and in 1964 published ''The Vertebrates of Arizona''. His research in the 1960s established the parthenogenetic reproduction of many whiptail lizard species, and also discovered that the desert pupfish can tolerate temperatures up to 44 °C (112 °F) and extremely low oxygen levels. He discovered twenty new species and subspecies In Taxonomy (biology), biological classification, subspecies (: subspecies) is a rank below species, used for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyploidy
Polyploidy is a condition in which the cells of an organism have more than two paired sets of ( homologous) chromosomes. Most species whose cells have nuclei (eukaryotes) are diploid, meaning they have two complete sets of chromosomes, one from each of two parents; each set contains the same number of chromosomes, and the chromosomes are joined in pairs of homologous chromosomes. 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 p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taxa Named By John William Wright (herpetologist)
In biology, a taxon (back-formation from ''taxonomy''; : taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and given a particular ranking, especially if and when it is accepted or becomes established. It is very common, however, for taxonomists to remain at odds over what belongs to a taxon and the criteria used for inclusion, especially in the context of rank-based (" Linnaean") nomenclature (much less so under phylogenetic nomenclature). If a taxon is given a formal scientific name, its use is then governed by one of the nomenclature codes specifying which scientific name is correct for a particular grouping. Initial attempts at classifying and ordering organisms (plants and animals) were presumably set forth in prehistoric times by hunter-gatherers, as suggested by the fairly sophisticated folk taxonomies. Much later, Aristotle, and later still ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taxa Named By Charles Herbert Lowe
In biology, a taxon (back-formation from ''Taxonomy (biology), taxonomy''; : taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and given a particular Taxonomic rank, ranking, especially if and when it is accepted or becomes established. It is very common, however, for taxonomists to remain at odds over what belongs to a taxon and the criteria used for inclusion, especially in the context of rank-based ("Linnaean taxonomy, Linnaean") nomenclature (much less so under phylogenetic nomenclature). If a taxon is given a formal scientific name, its use is then governed by one of the nomenclature codes specifying which scientific name is correct for a particular grouping. Initial attempts at classifying and ordering organisms (plants and animals) were presumably set forth in prehistoric times by hunter-gatherers, as suggested by the fairly sophisticated f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fauna Of The Southwestern United States
Fauna (: faunae or faunas) is all of the animal life present in a particular region or time. The corresponding terms for plants and fungi are ''flora'' and '' funga'', respectively. Flora, fauna, funga and other forms of life are collectively referred to as '' biota''. Zoologists and paleontologists use ''fauna'' to refer to a typical collection of animals found in a specific time or place, e.g. the " Sonoran Desert fauna" or the " Burgess Shale fauna". Paleontologists sometimes refer to a sequence of faunal stages, which is a series of rocks all containing similar fossils. The study of animals of a particular region is called faunistics. Etymology ''Fauna'' comes from the name Fauna, a Roman goddess of earth and fertility, the Roman god Faunus, and the related forest spirits called Fauns. All three words are cognates of the name of the Greek god Pan, and ''panis'' is the Modern Greek equivalent of fauna (πανίς or rather πανίδα). ''Fauna'' is also the word for a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fauna Of The Sonoran Desert
The Sonoran Desert () is a hot desert and ecoregion in North America that covers the northwestern Mexican states of Sonora, Baja California, and Baja California Sur, as well as part of the Southwestern United States (in Arizona and California). It is the hottest desert in Mexico. It has an area of . In phytogeography, the Sonoran Desert is within the Sonoran floristic province of the Madrean region of southwestern North America, part of the Holarctic realm of the northern Western Hemisphere. The desert contains a variety of unique endemism, endemic plants and animals, notably, the saguaro (''Carnegiea gigantea'') and Stenocereus thurberi, organ pipe cactus (''Stenocereus thurberi''). The Sonoran Desert is clearly distinct from nearby deserts (e.g., the Great Basin Desert, Great Basin, Mojave Desert, Mojave, and Chihuahuan Desert, Chihuahuan deserts) because it provides subtropical warmth in winter and two seasons of rainfall (in contrast, for example, to the Mojave's dry summers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fauna Of The Chihuahuan Desert
Fauna (: faunae or faunas) is all of the animal life present in a particular region or time. The corresponding terms for plants and fungi are ''flora'' and ''funga'', respectively. Flora, fauna, funga and other forms of life are collectively referred to as '' biota''. Zoologists and paleontologists use ''fauna'' to refer to a typical collection of animals found in a specific time or place, e.g. the "Sonoran Desert fauna" or the "Burgess Shale fauna". Paleontologists sometimes refer to a sequence of faunal stages, which is a series of rocks all containing similar fossils. The study of animals of a particular region is called faunistics. Etymology ''Fauna'' comes from the name Fauna, a Roman goddess of earth and fertility, the Roman god Faunus, and the related forest spirits called Fauns. All three words are cognates of the name of the Greek god Pan, and ''panis'' is the Modern Greek equivalent of fauna (πανίς or rather πανίδα). ''Fauna'' is also the word for a boo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reptiles Described In 1965
Reptiles, as commonly defined, are a group of tetrapods with an ectothermic metabolism and Amniotic egg, amniotic development. Living traditional reptiles comprise four Order (biology), orders: Testudines, Crocodilia, Squamata, and Rhynchocephalia. About 12,000 living species of reptiles are listed in the Reptile Database. The study of the traditional reptile orders, customarily in combination with the study of modern amphibians, is called herpetology. Reptiles have been subject to several conflicting Taxonomy, taxonomic definitions. In Linnaean taxonomy, reptiles are gathered together under the Class (biology), class Reptilia ( ), which corresponds to common usage. Modern Cladistics, cladistic taxonomy regards that group as Paraphyly, paraphyletic, since Genetics, genetic and Paleontology, paleontological evidence has determined that birds (class Aves), as members of Dinosauria, are more closely related to living crocodilians than to other reptiles, and are thus nested among re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reptiles Of The United States
Reptiles, as commonly defined, are a group of tetrapods with an ectothermic metabolism and amniotic development. Living traditional reptiles comprise four orders: Testudines, Crocodilia, Squamata, and Rhynchocephalia. About 12,000 living species of reptiles are listed in the Reptile Database. The study of the traditional reptile orders, customarily in combination with the study of modern amphibians, is called herpetology. Reptiles have been subject to several conflicting taxonomic definitions. In Linnaean taxonomy, reptiles are gathered together under the class Reptilia ( ), which corresponds to common usage. Modern cladistic taxonomy regards that group as paraphyletic, since genetic and paleontological evidence has determined that birds (class Aves), as members of Dinosauria, are more closely related to living crocodilians than to other reptiles, and are thus nested among reptiles from an evolutionary perspective. Many cladistic systems therefore redefine Reptilia as a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aspidoscelis
''Aspidoscelis'' is a genus of whiptail lizards in the family Teiidae. Taxonomy The nomenclature for the genus ''Aspidoscelis'' was published by T.W. Reeder et al. in 2002. Many species that were formerly included in the genus '' Cnemidophorus'' are now considered ''Aspidoscelis'' based upon divergent characters between the two groups. Etymology The name ''Aspidoscelis'' literally means "shield-leg", from the Ancient Greek ("shield") and ("leg"). Species The following species are recognized as being valid. *'' Aspidoscelis angusticeps'' – Yucatán whiptail *'' Aspidoscelis arizonae'' – Arizona striped whiptail *''Aspidoscelis burti'' – canyon spotted whiptail *'' Aspidoscelis calidipes'' – Tepalcatepec Valley whiptail *'' Aspidoscelis carmenensis'' – Carmen Island whiptail *''Aspidoscelis ceralbensis'' – Cerralvo Island whiptail *''Aspidoscelis communis'' – Colima giant whiptail *''Aspidoscelis costatus'' – western Mexico whiptail lizard *''Aspidos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sister Chromatids
A sister chromatid refers to the identical copies ( chromatids) formed by the DNA replication of a chromosome, with both copies joined together by a common centromere. In other words, a sister chromatid may also be said to be 'one-half' of the duplicated chromosome. A pair of sister chromatids is called a dyad. A full set of sister chromatids is created during the synthesis ( S) phase of interphase, when all the chromosomes in a cell are replicated. The two sister chromatids are separated from each other into two different cells during mitosis or during the second division of meiosis. Compare sister chromatids to homologous chromosomes, which are the two ''different'' copies of a chromosome that diploid organisms (like humans) inherit, one from each parent. Sister chromatids are by and large identical (since they carry the same alleles, also called variants or versions, of genes) because they derive from one original chromosome. An exception is towards the end of meiosis, after ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
