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Thick-billed Raven
The thick-billed raven (''Corvus crassirostris''), a corvid from the Horn of Africa, shares with the common raven the distinction of being the largest bird in the corvid family, and indeed the largest of the passerines. The thick-billed raven averages in length, with a range of and weighs approximately in females and in males on average. Its size is about the same as the largest subspecies of common raven (i.e. those from the Himalayas and Greenland/Canadian Northwest Atlantic) but some common raven subspecies are rather smaller and, going on average weights, the thick-billed raven is likely the heaviest extant passerine. The thick-billed raven is about 25% heavier on average than the Australasian superb lyrebird, which is sometimes erroneously titled the largest passerine.Madge, S. (2010). ''Crows and jays''. A&C Black. It has a very large bill that is laterally compressed and is deeply curved in profile giving the bird a very distinctive appearance. This bill, the largest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eduard Rüppell
Wilhelm Peter Eduard Simon Rüppell (20 November 1794 – 10 December 1884) was a German Natural history, naturalist and List of explorers, explorer. Rüppell is occasionally transliterated to "Rueppell" for the English alphabet, due to german orthography. Biography Rüppell was born in Frankfurt am Main, the son of a prosperous banker, who was a partner in 'Rüppell und Harnier’s Bank'. He was originally destined to be a merchant, but after a visit to Sinai Peninsula, Sinai in 1817, where he met Henry Salt (Egyptologist), Henry Salt and the Swiss-German traveller Johann Ludwig Burckhardt, Ludwig Burckhardt. He explored Giza and the Pyramids with Salt. In 1818, he developed an interest in natural history, and became elected member of the ''Senckenbergische Naturforschende Gesellschaf''. He attended lectures at the University of Pavia and University of Genoa in botany and zoology. Rüppell set off on his first expedition in 1821, accompanied by surgeon Michael Hey as his assistan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mountain
A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. Although definitions vary, a mountain may differ from a plateau in having a limited Summit (topography), summit area, and is usually higher than a hill, typically rising at least 300 metres (1,000 feet) above the surrounding land. A few mountains are Monadnock, isolated summits, but most occur in mountain ranges. Mountain formation, Mountains are formed through Tectonic plate, tectonic forces, erosion, or volcanism, which act on time scales of up to tens of millions of years. Once mountain building ceases, mountains are slowly leveled through the action of weathering, through Slump (geology), slumping and other forms of mass wasting, as well as through erosion by rivers and glaciers. High elevations on mountains produce Alpine climate, colder climates than at sea level at similar latitude. These colder climates strongly affect the Montane ecosystems, ecosys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ravens
Ravens may refer to: * Raven, a species of the genus ''Corvus'' Sports * Anderson Ravens, the intercollegiate athletic program of Anderson University in Indiana * Baltimore Ravens, a professional American football franchise * Benedictine Ravens, the official mascot of Benedictine College * Carleton Ravens, the intercollegiate athletic program of Carleton University in Canada * Munich Ravens, German american-football team in the European League of Football * Quincy Ravens, an 1890s minor league baseball team in Illinois * Vancouver Ravens, a team that used to play in the National Lacrosse League Other uses * ''Ravens'' (film), a 2017 Swedish thriller film * The Ravens, an American R&B music band * "Ravens", a song by Patti Smith from ''Gone Again'' * ''Ravens'', a 2009 novel by George Dawes Green People with the surname * Jan Ravens (born 1958), an English actress and impressionist See also * Raven (other) * Raven's Progressive Matrices Raven's Progressive Matrices ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corvus
''Corvus'' is a widely distributed genus of medium-sized to large birds in the family Corvidae. It includes species commonly known as crows, ravens and Rook (bird), rooks. The species commonly encountered in Europe are the carrion crow, the hooded crow, the common raven and the rook (bird), rook; those discovered later were named "crow" or "raven" chiefly on the basis of their size, crows generally being smaller. The genus name is Latin for "crow". The List of Corvus species, 45 or so members of this genus occur on all temperate continents except South America, and several islands. The ''Corvus'' genus makes up a third of the species in the family Corvidae. The members appear to have evolved in Asia from the corvid stock, which had evolved in Australia. The collective noun, collective name for a group of crows is a "flock" or a "murder". Recent research has found some crow species capable of not only Tool use by animals, tool use, but also tool construction. Crows are now consi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Verreaux's Eagle Owl
Verreaux's eagle-owl (''Bubo lacteus''), also commonly known as the milky eagle owl or giant eagle owl, is a member of the family Strigidae. This species is widespread in sub-Saharan Africa. A member of the genus ''Bubo'', it is the largest African owl, measuring up to in total length. This eagle-owl is a resident primarily of dry, wooded savanna. Verreaux's eagle-owl is mainly grey in color and is distinguishable from other large owls by its bright pink eyelids, a feature shared with no other owl species in the world.König, C., & Weick, F. (2008). ''Owls of the World''. A&C Black. . Verreaux's eagle-owl is a highly opportunistic predator equipped with powerful talons. Just over half of its known diet is composed of mammals but equal or even greater numbers of birds and even insects may be hunted locally, along with any other appropriately sized prey that is encountered.Brown, L. H. (1965). ''Observations on Verreaux's Eagle Owl Bubo lacteus (Temminck) in Kenya''. ''Journal of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Egg (biology)
An egg is an organic vessel grown by an animal to carry a possibly fertilized egg cell (a zygote) and to incubate from it an embryo within the egg until the embryo has become an animal fetus that can survive on its own, at which point the animal hatches. Most arthropods such as insects, vertebrates (excluding live-bearing mammals), and mollusks lay eggs, although some, such as scorpions, do not. Reptile eggs, bird eggs, and monotreme eggs are laid out of water and are surrounded by a protective shell, either flexible or inflexible. Eggs laid on land or in nests are usually kept within a warm and favorable temperature range while the embryo grows. When the embryo is adequately developed it hatches, i.e., breaks out of the egg's shell. Some embryos have a temporary egg tooth they use to crack, pip, or break the eggshell or covering. The largest recorded egg is from a whale shark and was in size. Whale shark eggs typically hatch within the mother. At and up to , the o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
White-necked Raven
The white-necked raven (''Corvus albicollis'') is somewhat smaller (50–54 cm in length) than the common raven or its nearest relative, the thick-billed raven ''C. crassirostris''. It is native to eastern and southern Africa. Description The white-necked raven has a much shorter tail than the common raven, as well as a deeper bill with a white tip that is almost as strongly arched as that of the thick-billed raven. Though predominantly black, the throat, breast and neck show a faint purple gloss. There is a large patch of white feathers on the nape of the neck. Soars well with shallower wingbeats than other Corvidae. Measurements * Length: 50 – 54 cm * Wingspan: 752 – 860 mm (17 unsexed birds) * Weight: 762 - 865 g Vocalisation Often described as a raven with a sore throat, it has very similar calls to the common raven, but with a more husky note. It has a croak like the other raven species but with a more whispering note. Like all corvids, the White-ne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bird Nest
A bird nest is the spot in which a bird lays and incubates its eggs and raises its young. Although the term popularly refers to a specific structure made by the bird itself—such as the grassy cup nest of the American robin or Eurasian blackbird, or the elaborately woven hanging nest of the Montezuma oropendola or the village weaver—that is too restrictive a definition. For some species, a nest is simply a shallow depression made in sand; for others, it is the knot-hole left by a broken branch, a burrow dug into the ground, a chamber drilled into a tree, an enormous rotting pile of vegetation and earth, a shelf made of dried saliva or a mud dome with an entrance tunnel. The smallest bird nests are those of some hummingbirds, tiny cups which can be a mere across and high. At the other extreme, some nest mounds built by the dusky scrubfowl measure more than in diameter and stand nearly tall. The study of birds' nests is known as ''caliology''. Not all bird species bui ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cliff
In geography and geology, a cliff is an area of rock which has a general angle defined by the vertical, or nearly vertical. Cliffs are formed by the processes of weathering and erosion, with the effect of gravity. Cliffs are common on coasts, in mountainous areas, escarpments and along rivers. Cliffs are usually composed of rock that is resistant to weathering and erosion. The sedimentary rocks that are most likely to form cliffs include sandstone, limestone, chalk, and dolomite. Igneous rocks such as granite and basalt also often form cliffs. An escarpment (or scarp) is a type of cliff formed by the movement of a geologic fault, a landslide, or sometimes by rock slides or falling rocks which change the differential erosion of the rock layers. Most cliffs have some form of scree slope at their base. In arid areas or under high cliffs, they are generally exposed jumbles of fallen rock. In areas of higher moisture, a soil slope may obscure the talus. Many cliffs also fea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tree
In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are usable as lumber or plants above a specified height. In wider definitions, the taller palms, tree ferns, bananas, and bamboos are also trees. Trees are not a taxonomic group but include a variety of plant species that have independently evolved a trunk and branches as a way to tower above other plants to compete for sunlight. The majority of tree species are angiosperms or hardwoods; of the rest, many are gymnosperms or softwoods. Trees tend to be long-lived, some reaching several thousand years old. Trees have been in existence for 370 million years. It is estimated that there are some three trillion mature trees in the world. A tree typically has many secondary branches supported clear of the ground by the trunk. This trunk typically ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plateau
In geology and physical geography, a plateau (; ; ), also called a high plain or a tableland, is an area of a highland consisting of flat terrain that is raised sharply above the surrounding area on at least one side. Often one or more sides have deep hills or escarpments. Plateaus can be formed by a number of processes, including upwelling of volcanic magma, extrusion of lava, and erosion by water and glaciers. Plateaus are classified according to their surrounding environment as intermontane, piedmont, or continental. A few plateaus may have a small flat top while others have wide ones. Formation Plateaus can be formed by a number of processes, including upwelling of volcanic magma, extrusion of lava, Plate tectonics movements and erosion by water and glaciers. Volcanic Volcanic plateaus are produced by volcanic activity. The Columbia Plateau in the north-western United States is an example. They may be formed by upwelling of volcanic magma or extrusion of lava. The un ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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