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Aquatic Genet
The aquatic genet (''Genetta piscivora'') is a genet that has only been recorded in the northeast of the Democratic Republic of the Congo.Van Rompaey, H. and Colyn, M. (2013). ''Genetta piscivora'' Aquatic Genet. In: J. Kingdon and M. Hoffmann (eds.) The Mammals of Africa. V. Carnivores, Pangolins, Equids and Rhinoceroses, pp. 239–240. Bloomsbury, London, UK. Since it is only known from about 30 specimens in zoological collections, it had been listed as Data Deficient on the IUCN Red List since 1996, as it is considered one of Africa's rarest carnivores. In 2015, it has been reassessed as Near Threatened. When Allen described the aquatic genet as a new genus and species in 1919, he named it ''Osbornictis piscivora''.Allen, J. A. (1919). Preliminary notes on African Carnivora. Journal of Mammalogy 1 (1): 23–31. It was reassessed in 2004, and based on molecular evidence is now considered a '' Genetta'' species. Characteristics The aquatic genet's long and dense fur is dark ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Joel Asaph Allen
Joel Asaph Allen (July 19, 1838 – August 29, 1921) was an American zoology, zoologist, mammalogy, mammalogist, and ornithology, ornithologist. He became the first president of the American Ornithologists' Union, the first curator of birds and mammals at the American Museum of Natural History, and the first head of that museum's Department of Ornithology. He is remembered for Allen's rule, which states that the bodies of endotherms (warm-blooded animals) vary in shape with climate, having increased surface area in hot climates to lose heat, and minimized surface area in cold climates, to conserve heat. Early life Allen was born in Springfield, Massachusetts, the son of Joel Allen and Harriet Trumbull. He studied and collected specimen of natural history early in life, but he was forced to sell his relatively large collection so that he could attend the Wilbraham & Monson Academy in 1861. The following year, he transferred to Harvard University, where he studied under Louis Agassi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Congo River
The Congo River ( kg, Nzâdi Kôngo, french: Fleuve Congo, pt, Rio Congo), formerly also known as the Zaire River, is the second longest river in Africa, shorter only than the Nile, as well as the second largest river in the world by discharge volume, following only the Amazon. It is also the world's deepest recorded river, with measured depths around . The Congo- Lualaba- Chambeshi River system has an overall length of , which makes it the world's ninth- longest river. The Chambeshi is a tributary of the Lualaba River, and ''Lualaba'' is the name of the Congo River upstream of Boyoma Falls, extending for . Measured along with the Lualaba, the main tributary, the Congo River has a total length of . It is the only major river to cross the Equator twice. The Congo Basin has a total area of about , or 13% of the entire African landmass. Name The name ''Congo/Kongo'' originates from the Kingdom of Kongo once located on the southern bank of the river. The kingdom in turn was name ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reproduction
Reproduction (or procreation or breeding) is the biological process by which new individual organisms – "offspring" – are produced from their "parent" or parents. Reproduction is a fundamental feature of all known life; each individual organism exists as the result of reproduction. There are two forms of reproduction: asexual and sexual. In asexual reproduction, an organism can reproduce without the involvement of another organism. Asexual reproduction is not limited to single-celled organisms. The cloning of an organism is a form of asexual reproduction. By asexual reproduction, an organism creates a genetically similar or identical copy of itself. The evolution of sexual reproduction is a major puzzle for biologists. The two-fold cost of sexual reproduction is that only 50% of organisms reproduce and organisms only pass on 50% of their genes.John Maynard Smith ''The Evolution of Sex'' 1978. Sexual reproduction typically requires the sexual interaction of two specializ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gestation
Gestation is the period of development during the carrying of an embryo, and later fetus, inside viviparous animals (the embryo develops within the parent). It is typical for mammals, but also occurs for some non-mammals. Mammals during pregnancy can have one or more gestations at the same time, for example in a multiple birth. The time interval of a gestation is called the '' gestation period''. In obstetrics, ''gestational age'' refers to the time since the onset of the last menses, which on average is fertilization age plus two weeks. Mammals In mammals, pregnancy begins when a zygote (fertilized ovum) implants in the female's uterus and ends once the fetus leaves the uterus during labor or an abortion (whether induced or spontaneous). Humans In humans, pregnancy can be defined clinically or biochemically. Clinically, pregnancy starts from first day of the mother's last period. Biochemically, pregnancy starts when a woman's human chorionic gonadotropin (hCG) levels ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crustacean
Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group can be treated as a subphylum under the clade Mandibulata. It is now well accepted that the hexapods emerged deep in the Crustacean group, with the completed group referred to as Pancrustacea. Some crustaceans (Remipedia, Cephalocarida, Branchiopoda) are more closely related to insects and the other hexapods than they are to certain other crustaceans. The 67,000 described species range in size from '' Stygotantulus stocki'' at , to the Japanese spider crab with a leg span of up to and a mass of . Like other arthropods, crustaceans have an exoskeleton, which they moult to grow. They are distinguished from other groups of arthropods, such as insects, myriapods and chelicerates, by the possession of biramous (two-parted) limbs, and by th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyprinidae
Cyprinidae is a family of freshwater fish commonly called the carp or minnow family. It includes the carps, the true minnows, and relatives like the barbs and barbels. Cyprinidae is the largest and most diverse fish family and the largest vertebrate animal family in general with about 3,000 species, of which only 1,270 remain extant, divided into about 370 genera. Cyprinids range from about 12 mm in size to the giant barb (''Catlocarpio siamensis''). By genus and species count, the family makes up more than two-thirds of the ostariophysian order Cypriniformes. The family name is derived from the Greek word ( 'carp'). Biology and ecology Cyprinids are stomachless fish with toothless jaws. Even so, food can be effectively chewed by the gill rakers of the specialized last gill bow. These pharyngeal teeth allow the fish to make chewing motions against a chewing plate formed by a bony process of the skull. The pharyngeal teeth are unique to each species and are used by scient ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synodontis
''Synodontis'' is the largest genus of mochokid catfishes. It is the biggest genus within the 10 genera and 190 different species in the family Mochokidae. ''Synodontis'' has over 131 different species within the genus. ''Synodontis'' are also known as squeakers, due to their ability to make stridulatory sounds through their pectoral fin spines when handled or disturbed. ''Synodontis'' make a sound that sounds like squeaking by rubbing their spines together. They do this when they have been frightened or when they become angry. ''Synodontis'' may also squeak when they are taken out of the water. These catfish are small- to medium-sized fish with many species exhibiting attractive spotted markings. Some species are also known for naturally swimming belly-up, earning the name upside-down catfish. Some of these species are '' Synodontis contractus'' and '' Synodontis nigriventris''. While some of these species are known to swim upside down, another species, '' Synodontis multipunct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barbel (fish)
Barbels are group of small carp-like freshwater fish, almost all of the genus ''Barbus''. They are usually found in gravel and rocky-bottomed slow-flowing waters with high dissolved oxygen content. A typical adult barbel can range from 25 to 100 cm in length and weigh between 200 g and 10 kg, although weights of 200 g are more common. Babies weigh 100–150 g. Barbel roe is poisonous and causes vomiting and diarrhea in some people. However, the fish itself can be eaten and recipes are available in The Illustrated London Cookery Book by Frederick Bishop. The name barbel derived from the Latin ''barba'', meaning beard, a reference to the two pairs of barbels, a longer pair pointing forwards and slightly down positioned, on the side of the mouth. Fish described as barbels by English-speaking people may not be known as barbels in their native country, although the root of the word may be similar. For instance, the Mediterranean barbel (''Barbus meridionalis'') ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catfish
Catfish (or catfishes; order Siluriformes or Nematognathi) are a diverse group of ray-finned fish. Named for their prominent barbels, which resemble a cat's whiskers, catfish range in size and behavior from the three largest species alive, the Mekong giant catfish from Southeast Asia, the wels catfish of Eurasia, and the piraíba of South America, to detritivores (species that eat dead material on the bottom), and even to a tiny parasitic species commonly called the candiru, ''Vandellia cirrhosa''. Neither the armour-plated types nor the naked types have scales. Despite their name, not all catfish have prominent barbels or "whiskers". Members of the Siluriformes order are defined by features of the skull and swimbladder. Catfish are of considerable commercial importance; many of the larger species are farmed or fished for food. Many of the smaller species, particularly the genus ''Corydoras'', are important in the aquarium hobby. Many catfish are nocturnal, [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Freshwater Fish
Freshwater fish are those that spend some or all of their lives in fresh water, such as rivers and lakes, with a salinity of less than 1.05%. These environments differ from marine conditions in many ways, especially the difference in levels of salinity. To survive fresh water, the fish need a range of physiology, physiological adaptations. 41.24% of all known species of fish are found in fresh water. This is primarily due to the rapid speciation that the scattered habitats make possible. When dealing with ponds and lakes, one might use the same basic models of speciation as when studying island biogeography. Physiology Freshwater fish differ physiologically from salt water fish in several respects. Their gills must be able to diffuse dissolved gases while keeping the salts in the body fluids inside. Their scales reduce water diffusion through the skin: freshwater fish that have lost too many scales will die. They also have well developed kidneys to reclaim salts from body flui ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crepuscular
In zoology, a crepuscular animal is one that is active primarily during the twilight period, being matutinal, vespertine, or both. This is distinguished from diurnal and nocturnal behavior, where an animal is active during the hours of daylight and of darkness, respectively. Some crepuscular animals may also be active by moonlight or during an overcast day. Matutinal animals are active only before sunrise, and vespertine only after sunset. A number of factors impact the time of day an animal is active. Predators hunt when their prey is available, and prey try to avoid the times when their principal predators are at large. The temperature at midday may be too high or at night too low. Some creatures may adjust their activities depending on local competition. Etymology and usage The word ''crepuscular'' derives from the Latin '' crepusculum'' ("twilight"). Its sense accordingly differs from diurnal and nocturnal behavior, which respectively peak during hours of daylight and da ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Congo Basin
The Congo Basin (french: Bassin du Congo) is the sedimentary basin of the Congo River. The Congo Basin is located in Central Africa, in a region known as west equatorial Africa. The Congo Basin region is sometimes known simply as the Congo. It contains some of the largest tropical rainforests in the world and is an important source of water used in agriculture and energy generation. The rainforest in the Congo Basin is the largest rainforest in Africa and second only to the Amazon rainforest in size, with 300 million hectares compared to the 800 million hectares in the Amazon. Because of its size and diversity, many experts have characterized the basin's forest as important for mitigating climate change because of its role as a carbon sink. However, deforestation and degradation of the ecology by the impacts of climate change may increase stress on the forest ecosystem, in turn making the hydrology of the basin more variable. A 2012 study found that the variability in precipita ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
