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Pusa Caspica
The Caspian seal (''Pusa caspica'', syn. ''Phoca caspica'') is one of the smallest members of the earless seal family and unique in that it is found exclusively in the brackish Caspian Sea. It lives along the shorelines, but also on the many rocky islands and floating blocks of ice that dot the Caspian Sea. In winter and cooler parts of the spring and autumn season, it populates the northern Caspian coastline. As the ice melts in the summer and warmer parts of the spring and autumn season, it also occurs in the deltas of the Volga and Ural Rivers, as well as the southern latitudes of the Caspian where the water is cooler due to greater depth. Evidence suggests that the colonization events of Caspian seals were probably facilitated by river connections from the Arctic that have since disappeared, landlocking the populations sometime before the major Pleistocene glaciations. Description Adults are about in length. Males are longer than females at an early age, but females experi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johann Friedrich Gmelin
Johann Friedrich Gmelin (8 August 1748 – 1 November 1804) was a German natural history, naturalist, chemist, botanist, entomologist, herpetologist, and malacologist. Education Johann Friedrich Gmelin was born as the eldest son of Philipp Friedrich Gmelin in 1748 in Tübingen. He studied medicine under his father at University of Tübingen and graduated with a Master's degree in 1768, with a thesis entitled: ', defended under the presidency of Ferdinand Christoph Oetinger, whom he thanks with the words '. Career In 1769, Gmelin became an adjunct professor of medicine at University of Tübingen. In 1773, he became professor of philosophy and adjunct professor of medicine at University of Göttingen. He was promoted to full professor of medicine and professor of chemistry, botany, and mineralogy in 1778. He died in 1804 in Göttingen and is buried there in the Albanifriedhof, Albani cemetery with his wife Rosine Louise Gmelin (1755–1828, née Schott). Johann Friedrich Gm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Big-scale Sand Smelt
The big-scale sand smelt (''Atherina boyeri'') is a species of fish in the family Atherinidae. It is a euryhaline amphidromous fish, up to 20 cm in length. Description It is a small pelagic fish species which occurs near the surface in the littoral estuarine zone: in lagoons, salt marshes (77 psu), shallow brackish areas (2 psu) and inland waters which are rather unsuitable for other fish species, due to their high ionic strength and salinity. Body is rather long, slender, moderately flattened. Eyes are large. Head and body are scaly. Mouth is protractible, upwardly directed, with small teeth. Lower jaw has an upper expansion within mouth (high dentary bone). There are two separate dorsal fins, with all rays of first and 1–2 anterior rays of second dorsal fin being unsegmented. The anal fin is similar to the second dorsal fin, while the caudal fin is forked. The first dorsal fin has 6–10 flexible spines. It is an omnivorous species feeding on zoo-plankton and small bott ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apsheron Peninsula
The Absheron Peninsula () is a peninsula in Azerbaijan. It is the location of Baku, the most populous city of the country, and the Baku Metropolitan Area, with its satellite cities Sumqayit and Khyrdalan. It extends eastward into the Caspian Sea, and reaches a maximum width of . Azerbaijan's shape is often compared to an eagle, with the Absheron Peninsula forming its beak as it extends into the Caspian Sea. Though technically the easternmost extension of the Caucasus Mountains, the landscape is only mildly hilly, a gently undulating plain that ends in a long spit of sand dunes known as Shah Dili, also known as the Shah Spit which is the easternmost point of mainland Azerbaijan, now declared the Absheron National Park. In this part, the peninsula is dissected by ravines and characterized by frequent salt lakes. The peninsula also features four districts, of which two are urban (Baku and Sumqayit) while three are considered suburban ( Absheron Rayon, Pirallahi Rayon, and the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mangistau
Mangistau (, ''Mañğystau'') is a selo and the administrative center of Munaily District in Mangystau Region in western Kazakhstan. Mangistau is located in the desert on Mangyshlak Peninsula, east of Aktau and of the Caspian Sea The Caspian Sea is the world's largest inland body of water, described as the List of lakes by area, world's largest lake and usually referred to as a full-fledged sea. An endorheic basin, it lies between Europe and Asia: east of the Caucasus, ... coast. Population: References Populated places in Mangystau Region {{MangystauRegion-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canine Distemper
Canine distemper (CDV) (sometimes termed "footpad disease") is a viral disease that affects a wide variety of mammal families, including domestic and wild species of dogs, coyotes, foxes, pandas, wolves, ferrets, skunks, raccoons, and felines, as well as pinnipeds, some primates, and a variety of other species. CDV does not affect humans. In canines, CDV affects several body systems, including the gastrointestinal and respiratory tracts, the spinal cord, and the brain. Common symptoms include high fever, eye inflammation and eye/nose discharge, labored breathing and coughing, vomiting and diarrhea, loss of appetite and lethargy, and hardening of the nose and footpads. The viral infection can be accompanied by secondary bacterial infections and can eventually present serious neurological symptoms. Canine distemper is caused by a single-stranded RNA virus of the family ''Paramyxoviridae'' (the same family of viruses that causes measles, mumps, and bronchiolitis in humans). T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molt
In biology, moulting (British English), or molting (American English), also known as sloughing, shedding, or in many invertebrates, ecdysis, is a process by which an animal casts off parts of its body to serve some beneficial purpose, either at specific times of the year, or at specific points in its life cycle. In medieval times, it was also known as "mewing" (from the French verb "muer", to moult), a term that lives on in the name of Britain's Royal Mews where the King's hawks used to be kept during moulting time before becoming horse stables after Tudor times. Moulting can involve shedding the epidermis (skin), pelage (hair, feathers, fur, wool), or other external layer. In some groups, other body parts may be shed, for example, the entire exoskeleton in arthropods, including the wings in some insects. Examples In birds In birds, moulting is the periodic replacement of feathers by shedding old feathers while producing new ones. Feathers are dead structures at maturity w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Capital Breeding
Capital breeding and income breeding refer to the methods by which some organisms perform time breeding and use resources to finance their breeding. The former "describes the situation in which reproduction is financed using stored capital; hereas the latter ..refers to the use of concurrent intake to pay for a reproductive attempt." Income breeders who are growing especially fast hold off the development of their offspring after a threshold is reached so they can produce more offspring, although this does not occur in slower growing income breeders. An organism can be both a capital and an income breeder; the parasitoid '' Eupelmus vuilletti'', for example, is an income breeder in terms of sugars, but a capital breeder in terms of lipids. A different example of the interaction between capital and income breeding is found in ''Vipera aspis''; although these snakes are capital breeders, they lay larger litters when food is abundant, which is a characteristic of income breeders. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pelage
A fur is a soft, thick growth of hair that covers the skin of almost all mammals. It consists of a combination of oily guard hair on top and thick underfur beneath. The guard hair keeps moisture from reaching the skin; the underfur acts as an insulating blanket that keeps the animal warm. The fur of mammals has many uses: protection, sensory purposes, waterproofing, and camouflaging, with the primary usage being thermoregulation. The types of hair include * ''definitive'', which may be shed after reaching a certain length; * '' vibrissae'', which are sensory hairs and are most commonly whiskers; * ''pelage'', which consists of guard hairs, under-fur, and awn hair; * '' spines'', which are a type of stiff guard hair used for defense in, for example, porcupines; * ''bristles'', which are long hairs usually used in visual signals, such as the mane of a lion; * ''velli'', often called "down fur", which insulates newborn mammals; and * ''wool'', which is long, soft, and ofte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radionuclides
A radionuclide (radioactive nuclide, radioisotope or radioactive isotope) is a nuclide that has excess numbers of either neutrons or protons, giving it excess nuclear energy, and making it unstable. This excess energy can be used in one of three ways: emitted from the nucleus as gamma radiation; transferred to one of its electrons to release it as a conversion electron; or used to create and emit a new particle (alpha particle or beta particle) from the nucleus. During those processes, the radionuclide is said to undergo radioactive decay. These emissions are considered ionizing radiation because they are energetic enough to liberate an electron from another atom. The radioactive decay can produce a stable nuclide or will sometimes produce a new unstable radionuclide which may undergo further decay. Radioactive decay is a random process at the level of single atoms: it is impossible to predict when one particular atom will decay. However, for a collection of atoms of a single nucl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organochlorine Compound
Organochlorine chemistry is concerned with the properties of organochlorine compounds, or organochlorides, organic compounds that contain one or more carbon–chlorine bonds. The chloroalkane class (alkanes with one or more hydrogens substituted by chlorine) includes common examples. The wide structural variety and divergent chemical properties of organochlorides lead to a broad range of names, applications, and properties. Organochlorine compounds have wide use in many applications, though some are of profound environmental concern, with TCDD being one of the most notorious. Organochlorides such as trichloroethylene, tetrachloroethylene, dichloromethane and chloroform are commonly used as solvents and are referred to as "chlorinated solvents". Physical and chemical properties Chlorination modifies the physical properties of hydrocarbons in several ways. These compounds are typically denser than water due to the higher atomic weight of chlorine versus hydrogen. They have highe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heavy Metals
upright=1.2, Crystals of lead.html" ;"title="osmium, a heavy metal nearly twice as dense as lead">osmium, a heavy metal nearly twice as dense as lead Heavy metals is a controversial and ambiguous term for metallic elements with relatively high density, densities, atomic weights, or atomic numbers. The criteria used, and whether metalloids are included, vary depending on the author and context and it has been argued that the term "heavy metal" should be avoided. A heavy metal may be defined on the basis of density, atomic number or chemical behaviour. More specific definitions have been published, none of which have been widely accepted. The definitions surveyed in this article encompass up to 96 out of the 118 known chemical elements; only mercury, lead and bismuth meet all of them. Despite this lack of agreement, the term (plural or singular) is widely used in science. A density of more than 5 g/cm3 is sometimes quoted as a commonly used criterion and is used in the b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carp
The term carp (: carp) is a generic common name for numerous species of freshwater fish from the family (biology), family Cyprinidae, a very large clade of ray-finned fish mostly native to Eurasia. While carp are prized game fish, quarries and are valued (even pisciculture, commercially cultivated) as both food fish, food and ornamental fish in many parts of the Old World, they are considered trash fish and invasive species, invasive pest (organism), pests in many parts of Africa, Australia and most of the United States. Biology The cypriniformes (family Cyprinidae) are traditionally grouped with the Characiformes, Siluriformes, and Gymnotiformes to create the superorder Ostariophysi, since these groups share some common features. These features include being found predominantly in fresh water and possessing Weberian ossicles, an anatomical structure derived from the first five anterior-most vertebrae, and their corresponding ribs and neural crests. The third anterior-most pair ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
