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Galerella Nigeriensis
''Herpestes'' is a genus within the mongoose family Herpestidae. Several species in the family are known as slender mongooses. It is the type genus of the family, and comprises 5-6 living species, each with several subspecies. Fossil remains of three prehistoric species were excavated in France, and described in 1853. Characteristics The living ''Herpestes'' species are sexually dimorphic, with females smaller than males. They range in weight from . They share several characteristics, including the shape of the cheek teeth and of the tympanic bullae, and the presence of the first upper molar teeth. They are all solitary. Males have one chromosome less than females, as one Y chromosome is translocated to an autosome. Classification The scientific name ''Herpestes'' was proposed by Johann Karl Wilhelm Illiger in 1811 for mongoose species in the south of the Old World, commonly called "Ichneumon" at the time. Until 1835, 12 mongoose species from Africa and Asia were c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligocene
The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the exact dates of the start and end of the epoch are slightly uncertain. The name Oligocene was coined in 1854 by the German paleontologist Heinrich Ernst Beyrich from his studies of marine beds in Belgium and Germany. The name comes from the Ancient Greek (''olígos'', "few") and (''kainós'', "new"), and refers to the sparsity of extant forms of molluscs. The Oligocene is preceded by the Eocene Epoch and is followed by the Miocene Epoch. The Oligocene is the third and final epoch of the Paleogene Period. The Oligocene is often considered an important time of transition, a link between the archaic world of the tropical Eocene and the more modern ecosystems of the Miocene. Major changes during the Oligocene included a global expansion o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cheek Teeth
Cheek teeth or post-canines comprise the molar and premolar teeth in mammals. Cheek teeth are multicuspidate (having many folds or tubercles). Mammals have multicuspidate molars (three in placentals, four in marsupials, in each jaw quadrant) and premolars situated between canines and molars whose shape and number varies considerably among particular groups. For example, many modern Carnivora possess carnassials, or secodont teeth. This scissor-like pairing of the last upper premolar and first lower molar is adapted for shearing meat. In contrast, the cheek teeth of deer and cattle are selenodont. Viewed from the side, these teeth have a series of triangular cusps or ridges, enabling the ruminants' sideways jaw motions to break down tough vegetable matter. Cheek teeth are sometimes separated from the incisors by a gap called a diastema. Cheek teeth in reptiles are much simpler as compared to mammals. Roles and significance Apart from helping grind the food to properly reduce th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sole (foot)
The sole is the bottom of the foot. In humans the sole of the foot is anatomically referred to as the plantar aspect. Structure The glabrous skin on the sole of the foot lacks the hair and pigmentation found elsewhere on the body, and it has a high concentration of sweat pores. The sole contains the thickest layers of skin on the body due to the weight that is continually placed on it. It is crossed by a set of creases that form during the early stages of embryonic development. Like those of the palm, the sweat pores of the sole lack sebaceous glands. The sole is a sensory organ by which we can perceive the ground while standing and walking. The subcutaneous tissue in the sole has adapted to deal with the high local compressive forces on the heel and the ball (between the toes and the arch) by developing a system of "pressure chambers." Each chamber is composed of internal fibrofatty tissue covered by external collagen connective tissue. The septa (internal walls) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural History Museum
A natural history museum or museum of natural history is a scientific institution with natural history collections that include current and historical records of animals, plants, fungi, ecosystems, geology, paleontology, climatology, and more. History The primary role of a natural history museum is to provide the scientific community with current and historical specimens for their research, which is to improve our understanding of the natural world. Some museums have public exhibits to share the beauty and wonder of the natural world with the public; these are referred to as 'public museums'. Some museums feature non-natural history collections in addition to their primary collections, such as ones related to history, art, and science. Renaissance cabinets of curiosities were private collections that typically included exotic specimens of national history, sometimes faked, along with other types of object. The first natural history museum was possibly that of Swiss scholar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zoological Specimen
A zoological specimen is an animal or part of an animal preserved for scientific use. Various uses are: to verify the identity of a (species), to allow study, increase public knowledge of zoology. Zoological specimens are extremely diverse. Examples are bird and mammal study skins, mounted specimens, skeletal material, casts, pinned insects, dried material, animals preserved in liquid preservatives, and microscope slides. Natural history museums are repositories of zoological specimens Study skins Bird and mammal specimens are conserved as dry study skins, a form of taxidermy. The skin is removed from the animal's carcass, treated with absorbents, and filled with cotton or polyester batting (In the past plant fibres or sawdust were used). Bird specimens have a long, thin, wooden dowel wrapped in batting at their center. The dowel is often intentionally longer than the bird's body and exits at the animal's vent. This exposed dowel provides a place to handle the bird without distu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oldfield Thomas
Michael Rogers Oldfield Thomas (21 February 1858 – 16 June 1929) was a British zoologist. Career Thomas worked at the Natural History Museum on mammals, describing about 2,000 new species and subspecies for the first time. He was appointed to the museum secretary's office in 1876, transferring to the zoological department in 1878. In 1891, Thomas married Mary Kane, daughter of Sir Andrew Clark, heiress to a small fortune, which gave him the finances to hire mammal collectors and present their specimens to the museum. He also did field work himself in Western Europe and South America. His wife shared his interest in natural history, and accompanied him on collecting trips. In 1896, when William Henry Flower took control of the department, he hired Richard Lydekker Richard Lydekker (; 25 July 1849 – 16 April 1915) was an English naturalist, geologist and writer of numerous books on natural history. Biography Richard Lydekker was born at Tavistock Square in London. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viverridae
Viverridae is a family of small to medium-sized, feliform mammals. The viverrids () comprise 33 species placed in 14 genera. This family was named and first described by John Edward Gray in 1821. Viverrids occur all over Africa, southern Europe, and South and Southeast Asia, across the Wallace Line. Their occurrence in Sulawesi and in some of the adjoining islands shows them to be ancient inhabitants of the Old World tropics. Characteristics Viverrids have four or five toes on each foot and half-retractile claws. They have six incisors in each jaw and molars with two tubercular grinders behind in the upper jaw, and one in the lower jaw. The tongue is rough with sharp prickles. A pouch or gland occurs beneath the anus, but there is no cecum. Viverrids are the most primitive of all the families of feliform Carnivora and clearly less specialized than the Felidae. In external characteristics, they are distinguished from the Felidae by the longer muzzle and tuft of facial vibrissae ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Old World
The "Old World" is a term for Afro-Eurasia that originated in Europe , after Europeans became aware of the existence of the Americas. It is used to contrast the continents of Africa, Europe, and Asia, which were previously thought of by their inhabitants as comprising the entire world, with the "New World", a term for the newly encountered lands of the Western Hemisphere, particularly the Americas. Etymology In the context of archaeology and world history, the term "Old World" includes those parts of the world which were in (indirect) cultural contact from the Bronze Age onwards, resulting in the parallel development of the early civilizations, mostly in the temperate zone between roughly the 45th and 25th parallels north, in the area of the Mediterranean, including North Africa. It also included Mesopotamia, the Persian plateau, the Indian subcontinent, China, and parts of Sub-Saharan Africa. These regions were connected via the Silk Road trade route, and they have a p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scientific Name
In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin grammatical forms, although they can be based on words from other languages. Such a name is called a binomial name (which may be shortened to just "binomial"), a binomen, name or a scientific name; more informally it is also historically called a Latin name. The first part of the name – the '' generic name'' – identifies the genus to which the species belongs, whereas the second part – the specific name or specific epithet – distinguishes the species within the genus. For example, modern humans belong to the genus ''Homo'' and within this genus to the species ''Homo sapiens''. ''Tyrannosaurus rex'' is likely the most widely known binomial. The ''formal'' introduction of this system of naming species is credit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autosome
An autosome is any chromosome that is not a sex chromosome. The members of an autosome pair in a diploid cell have the same morphology, unlike those in allosome, allosomal (sex chromosome) pairs, which may have different structures. The DNA in autosomes is collectively known as atDNA or auDNA. For example, humans have a diploid human genome, genome that usually contains 22 pairs of autosomes and one allosome pair (46 chromosomes total). The autosome pairs are labeled with numbers (1–22 in humans) roughly in order of their sizes in base pairs, while allosomes are labelled with their letters. By contrast, the allosome pair consists of two X chromosomes in females or one X and one Y chromosome in males. Unusual combinations of XYY syndrome, XYY, Klinefelter syndrome, XXY, Triple X syndrome, XXX, XXXX syndrome, XXXX, XXXXX syndrome, XXXXX or XXYY syndrome, XXYY, among Aneuploidy, other Salome combinations, are known to occur and usually cause developmental abnormalities. Autosomes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Y Chromosome
The Y chromosome is one of two sex chromosomes (allosomes) in therian mammals, including humans, and many other animals. The other is the X chromosome. Y is normally the sex-determining chromosome in many species, since it is the presence or absence of Y that determines the male or female sex of offspring produced in sexual reproduction. In mammals, the Y chromosome contains the gene SRY, which triggers male development. The DNA in the human Y chromosome is composed of about 59 million base pairs, making it similar in size to chromosome 19. The Y chromosome is passed only from father to son. With a 30% difference between humans and chimpanzees, the Y chromosome is one of the fastest-evolving parts of the human genome. The human Y chromosome carries an estimated 100–200 genes, with between 45 and 73 of these being protein-coding. All single-copy Y-linked genes are hemizygous (present on only one chromosome) except in cases of aneuploidy such as XYY syndrome or XXYY syndrome. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromosome
A chromosome is a long DNA molecule with part or all of the genetic material of an organism. In most chromosomes the very long thin DNA fibers are coated with packaging proteins; in eukaryotic cells the most important of these proteins are the histones. These proteins, aided by chaperone proteins, bind to and condense the DNA molecule to maintain its integrity. These chromosomes display a complex three-dimensional structure, which plays a significant role in transcriptional regulation. Chromosomes are normally visible under a light microscope only during the metaphase of cell division (where all chromosomes are aligned in the center of the cell in their condensed form). Before this happens, each chromosome is duplicated ( S phase), and both copies are joined by a centromere, resulting either in an X-shaped structure (pictured above), if the centromere is located equatorially, or a two-arm structure, if the centromere is located distally. The joined copies are now called si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
