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Ivory
Ivory is a hard, white material from the tusks (traditionally from elephants) and Tooth, teeth of animals, that consists mainly of dentine, one of the physical structures of teeth and tusks. The chemical structure of the teeth and tusks of mammals is the same, regardless of the species of origin, but ivory contains structures of mineralised collagen. The trade in certain teeth and tusks other than elephant is well established and widespread; therefore, "ivory" can correctly be used to describe any mammalian teeth or tusks of commercial interest which are large enough to be carved or scrimshawed. Besides natural ivory, ivory can also be produced synthetically, hence (unlike natural ivory) not requiring the retrieval of the material from animals. Tagua nuts can also be carved like ivory. The trade of finished goods of ivory products has its origins in the Indus Valley. Ivory is a main product that is seen in abundance and was used for trading in Harappan civilization. Finished iv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ivory Carving
Ivory carving is the carving of ivory, that is to say animal tooth or tusk, generally by using sharp cutting tools, either mechanically or manually. Objects carved in ivory are often called "ivories". Humans have ornamentally carved ivory since prehistoric times, though until the 19th-century opening-up of the interior of Africa, it was usually a rare and expensive material used for small luxury products. Very fine detail can be achieved, and as the material, unlike precious metals, has no bullion value and usually cannot easily be recycled, the survival rate for ivory pieces is much higher than for those in other materials. Ivory carving has a special importance to the medieval art of Europe because of this, and in particular for Byzantine art as so little monumental sculpture was produced or has survived. As the elephant and other ivory-producing species have become endangered, largely because of hunting for ivory, CITES and national legislation in most countries have redu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elephant
Elephants are the largest living land animals. Three living species are currently recognised: the African bush elephant ('' Loxodonta africana''), the African forest elephant (''L. cyclotis''), and the Asian elephant ('' Elephas maximus''). They are the only surviving members of the family Elephantidae and the order Proboscidea; extinct relatives include mammoths and mastodons. Distinctive features of elephants include a long proboscis called a trunk, tusks, large ear flaps, pillar-like legs, and tough but sensitive grey skin. The trunk is prehensile, bringing food and water to the mouth and grasping objects. Tusks, which are derived from the incisor teeth, serve both as weapons and as tools for moving objects and digging. The large ear flaps assist in maintaining a constant body temperature as well as in communication. African elephants have larger ears and concave backs, whereas Asian elephants have smaller ears and convex or level backs. Elephants are scatter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
African Elephant
African elephants are members of the genus ''Loxodonta'' comprising two living elephant species, the African bush elephant (''L. africana'') and the smaller African forest elephant (''L. cyclotis''). Both are social herbivores with grey skin. However, they differ in the size and colour of their tusks as well as the shape and size of their ears and skulls. Both species are at a pertinent risk of extinction according to the IUCN Red List; as of 2021, the bush elephant is considered endangered while the forest elephant is considered critically endangered. They are threatened by habitat loss and fragmentation, along with poaching for the illegal ivory trade in several range countries. ''Loxodonta'' is one of two extant genera in the family Elephantidae. The name refers to the lozenge-shaped enamel of their molar teeth. Fossil remains of ''Loxodonta'' species have been found in Africa, spanning from the Late Miocene (from around 7–6 million years ago) onwards. Etymology T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scrimshaw
Scrimshaw is scrollwork, engravings, and carvings done in bone or ivory. Typically it refers to the artwork created by whalers, engraved on the byproducts of whales, such as bones or cartilage. It is most commonly made out of the bones and teeth of sperm whales, the baleen of other whales, and the tusks of walruses. It takes the form of elaborate engravings in the form of pictures and lettering on the surface of the bone or tooth, with the engraving highlighted using a pigment, or, less often, small sculptures made from the same material. However, the latter really fall into the categories of ivory carving, for all carved teeth and tusks, or bone carving. The making of scrimshaw probably began on whaling ships in the late 18th century and survived until the ban on commercial whaling. The practice survives as a hobby and as a trade for commercial artisans. A maker of scrimshaw is known as a ''scrimshander''. The word first appeared in the logbook of the brig ''By Chance'' in 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tagua
''Phytelephas'' is a genus containing six known species of dioecious palms (family Arecaceae), occurring from southern Panama along the Andes to Ecuador, Bolivia, Colombia, northwestern Brazil, and Peru. They are commonly known as ivory palms, ivory-nut palms or tagua palms (); the scientific name ''Phytelephas'' means "plant ivory" or more literally, "plant elephant". This and the first two of the common names refer to the very hard white endosperm of their seeds (tagua nuts or jarina seeds), which resembles elephant ivory. Description They are medium-sized to tall palms reaching up to 20 m tall, with pinnate leaves. The "nut" is covered with pericarp, which gets removed by animals. The kernel is covered with a brown, flaky skin and shaped like a small avocado, roughly 4–8 cm in diameter. The male plants produce catkins up to three feet (0.9 meter) in length of male flowers, each bearing up to one thousand stamens, the greatest number of any Monocot. Uses Given trade r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mammal
A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three Evolution of mammalian auditory ossicles, middle ear bones. These characteristics distinguish them from reptiles and birds, from which their ancestors Genetic divergence, diverged in the Carboniferous Period over 300 million years ago. Around 6,640 Neontology#Extant taxon, extant species of mammals have been described and divided into 27 Order (biology), orders. The study of mammals is called mammalogy. The largest orders of mammals, by number of species, are the rodents, bats, and eulipotyphlans (including hedgehogs, Mole (animal), moles and shrews). The next three are the primates (including humans, monkeys and lemurs), the Artiodactyl, even-toed ungulates (including pigs, camels, and whales), and the Carnivora (including Felidae, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sperm Whale
The sperm whale or cachalot (''Physeter macrocephalus'') is the largest of the toothed whales and the largest toothed predator. It is the only living member of the Genus (biology), genus ''Physeter'' and one of three extant species in the sperm whale superfamily Physeteroidea, along with the pygmy sperm whale and dwarf sperm whale of the genus ''Kogia''. The sperm whale is a pelagic mammal with a worldwide range, and will migrate seasonally for feeding and breeding. Females and young males live together in groups, while mature males (bulls) live solitary lives outside of the mating season. The females cooperate to protect and Lactation, nurse their young. Females give birth every four to twenty years, and care for the calves for more than a decade. A mature, healthy sperm whale has no natural predators, although calves and weakened adults are sometimes killed by Cetacea#Social relations, pods of killer whales (orcas). Mature males average in length, with the head represent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hippopotamus
The hippopotamus (''Hippopotamus amphibius;'' ; : hippopotamuses), often shortened to hippo (: hippos), further qualified as the common hippopotamus, Nile hippopotamus and river hippopotamus, is a large semiaquatic mammal native to sub-Saharan Africa. It is one of only two extant species in the family Hippopotamidae, the other being the pygmy hippopotamus (''Choeropsis liberiensis'' or ''Hexaprotodon liberiensis''). Its name comes from the ancient Greek for "river horse" (). After elephants and rhinoceroses, the hippopotamus is the next largest land mammal. It is also the largest extant land artiodactyl. Despite their physical resemblance to pigs and other terrestrial even-toed ungulates, the closest living relatives of the hippopotamids are cetaceans (whales, dolphins, porpoises, etc.), from which they diverged about 55 million years ago. Hippos are recognisable for their barrel-shaped torsos, wide-opening mouths with large canine tusks, nearly hairless bodies, pillar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Walrus
The walrus (''Odobenus rosmarus'') is a large pinniped marine mammal with discontinuous distribution about the North Pole in the Arctic Ocean and subarctic seas of the Northern Hemisphere. It is the only extant species in the family Odobenidae and genus ''Odobenus''. This species is subdivided into two subspecies: the Atlantic walrus (''O. r. rosmarus''), which lives in the Atlantic Ocean, and the Pacific walrus (''O. r. divergens''), which lives in the Pacific Ocean. Adult walrus are characterised by prominent tusks and whiskers, and considerable bulk: adult males in the Pacific can weigh more than and, among pinnipeds, are exceeded in size only by the two species of elephant seals. Walrus live mostly in shallow waters above the continental shelves, spending significant amounts of their lives on the sea ice looking for benthic bivalve molluscs. Walruses are relatively long-lived, social animals, and are considered to be a " keystone species" in the Arctic marine regio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Narwhal
The narwhal (''Monodon monoceros'') is a species of toothed whale native to the Arctic. It is the only member of the genus ''Monodon'' and one of two living representatives of the family Monodontidae. The narwhal is a stocky cetacean with a relatively blunt snout, a large Melon (whale), melon, and a shallow ridge in place of a dorsal fin. Males of this species have a large () long tusk, which is a protruding left Canine tooth, canine thought to function as a weapon, a tool for feeding, in sexual selection, attracting mates or sensing water salinity. Specially adapted slow-twitch muscles, along with the jointed neck vertebrae and shallow dorsal ridge allow for easy movement through the Arctic environment, where the narwhal spends extended periods at great depths. The narwhal's geographic range overlaps with that of the similarly built and closely related beluga whale, and the animals are known to interbreed. Narwhals inhabit the Arctic waters of Canada, Greenland and Russia. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
False Teeth
Dentures (also known as false teeth) are prosthetic devices constructed to replace missing teeth, supported by the surrounding soft and hard tissues of the oral cavity. Conventional dentures are removable (removable partial denture or complete denture). However, there are many denture designs, some of which rely on bonding or clasping onto teeth or dental implants (fixed prosthodontics). There are two main categories of dentures, the distinction being whether they fit onto the mandibular arch or on the maxillary arch. Medical uses Dentures can help people via: * Mastication: chewing ability is improved by the replacement of edentulous (lacking teeth) areas with denture teeth. * Aesthetics: the presence of teeth gives a natural appearance to the face, and wearing a denture to replace missing teeth provides support for the lips and cheeks and corrects the collapsed appearance that results from the loss of teeth. * Pronunciation: replacing missing teeth, especially the anteri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tooth
A tooth (: teeth) is a hard, calcified structure found in the jaws (or mouths) of many vertebrates and used to break down food. Some animals, particularly carnivores and omnivores, also use teeth to help with capturing or wounding prey, tearing food, for defensive purposes, to intimidate other animals often including their own, or to carry prey or their young. The roots of teeth are covered by gums. Teeth are not made of bone, but rather of multiple tissues of varying density and hardness that originate from the outermost embryonic germ layer, the ectoderm. The general structure of teeth is similar across the vertebrates, although there is considerable variation in their form and position. The teeth of mammals have deep roots, and this pattern is also found in some fish, and in crocodilians. In most teleost fish, however, the teeth are attached to the outer surface of the bone, while in lizards they are attached to the inner surface of the jaw by one side. In cartila ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
