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Orcas
The orca or killer whale (''Orcinus orca'') is a toothed whale belonging to the oceanic dolphin family, of which it is the largest member. It is the only extant species in the genus ''Orcinus'' and is recognizable by its black-and-white patterned body. A cosmopolitan species, orcas can be found in all of the world's oceans in a variety of marine environments, from Arctic and Antarctic regions to tropical seas. Orcas have a diverse diet, although individual populations often specialize in particular types of prey. Some feed exclusively on fish, while others hunt marine mammals such as seals and other species of dolphin. They have been known to attack baleen whale calves, and even adult whales. Orcas are apex predators, as they have no natural predators. They are highly social; some populations are composed of very stable matrilineal family groups (pods) which are the most stable of any animal species. Their sophisticated hunting techniques and vocal behaviours, which are o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toothed Whale
The toothed whales (also called odontocetes, systematic name Odontoceti) are a parvorder of cetaceans that includes dolphins, porpoises, and all other whales possessing teeth, such as the beaked whales and sperm whales. Seventy-three species of toothed whales are described. They are one of two living groups of cetaceans, the other being the baleen whales (Mysticeti), which have baleen instead of teeth. The two groups are thought to have diverged around 34 million years ago (mya). Toothed whales range in size from the and vaquita to the and sperm whale. Several species of odontocetes exhibit sexual dimorphism, in that there are size or other morphological differences between females and males. They have streamlined bodies and two limbs that are modified into flippers. Some can travel at up to 20 knots. Odontocetes have conical teeth designed for catching fish or squid. They have well-developed hearing, that is well adapted for both air and water, so much so that some can survi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oceanic Dolphin
Oceanic dolphins or Delphinidae are a widely distributed family of dolphins that live in the sea. Close to forty extant species are recognised. They include several big species whose common names contain "whale" rather than "dolphin", such as the Globicephalinae (round-headed whales including the orca and pilot whale). Delphinidae is a family within the superfamily Delphinoidea, which also includes the porpoises (Phocoenidae) and the Monodontidae (beluga whale and narwhal). River dolphins are relatives of the Delphinoidea. Oceanic dolphins range in size from the and Maui's dolphin to the and orca, the largest known dolphin. Several species exhibit sexual dimorphism; the males are larger than females. They have streamlined bodies and two limbs that are modified into flippers. Though not quite as flexible as seals, some dolphins can travel at speeds 29 km/h (18 mph) for short distances. Most delphinids primarily eat fish, along with a smaller number of squid a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pinniped
Pinnipeds (pronounced ), commonly known as seals, are a widely range (biology), distributed and diverse clade of carnivorous, fin-footed, semiaquatic, mostly marine mammal, marine mammals. They comprise the extant taxon, extant family (biology), families Odobenidae (whose only living member is the walrus), Otariidae (the eared seals: sea lions and fur seals), and Phocidae (the earless seals, or true seals). There are 34 extant species of pinnipeds, and more than 50 extinct species have been described from fossils. While seals were historically thought to have descended from two ancestral lines, molecular phylogenetics, molecular evidence supports them as a monophyletic lineage (descended from one ancestral line). Pinnipeds belong to the order Carnivora; their closest living relatives are Musteloidea, musteloids (Mustelidae, weasels, Procyonidae, raccoons, skunks, and red pandas), having diverged about 50 million years ago. Seals range in size from the and Baikal sea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orcinus
''Orcinus'' is a genus of Delphinidae, the family of carnivorous marine mammals known as dolphins. It includes the largest delphinid species, ''Orcinus orca'', known as the orca or killer whale. Two extinct species are recognised, '' Orcinus paleorca'' and '' O. citoniensis'', describing fossilised remains of the genus. The other extinct species '' O. meyeri'' is disputed. Taxonomy The genus ''Orcinus'' was published by Leopold Fitzinger in 1860, its type species is the orca named by Linnaeus in 1758 as ''Delphinus orca''. Taxonomic arrangements of delphinids published by workers before and after Fitzinger, such as John Edward Gray as ''Orca'' in 1846 and ''Orca'' (''Gladiator'') in 1870, are recognised as synonyms of ''Orcinus''. The descriptions of species as ''Orcinus glacialis'' Berzin and Vladimirov, 1983 and ''Orcinus nanus'' Mikhalev and Ivashin, 1981 are considered synonyms of ''Orcinus orca'', the existing species of orca. ''Orcinus'' means "of the kingdom of the dead" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polychlorinated Biphenyl
Polychlorinated biphenyls (PCBs) are highly carcinogenic chemical compounds, formerly used in industrial and consumer products, whose production was banned in the United States by the Toxic Substances Control Act in 1979 and internationally by the Stockholm Convention on Persistent Organic Pollutants in 2001. They are organic chlorine compounds with the formula C12 H10−''x'' Cl''x''; they were once widely used in the manufacture of carbonless copy paper, as heat transfer fluids, and as dielectric and coolant fluids for electrical equipment. Because of their longevity, PCBs are still widely in use, even though their manufacture has declined drastically since the 1960s, when a host of problems were identified. With the discovery of PCBs' environmental toxicity, and classification as persistent organic pollutants, their production was banned by United States federal law in 1978, and by the Stockholm Convention on Persistent Organic Pollutants in 2001. The International Agency ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marine Mammal Park
A marine mammal park (also known as marine animal park and sometimes oceanarium) is a commercial theme park or aquarium where marine mammals such as dolphins, beluga whales and sea lions are kept within water tanks and displayed to the public in special shows. A marine mammal park is more elaborate than a dolphinarium, because it also features other marine mammals and offers additional entertainment attractions. It is thus seen as a combination of a public aquarium and an amusement park. Marine mammal parks are different from marine parks, which include natural reserves and marine wildlife sanctuaries such as coral reefs, particularly in Australia. History Sea Lion Park opened in 1895 at Coney Island in Brooklyn, New York City with an aquatic show featuring 40 sea lions. It closed in 1903. The second marine mammal park, then called an oceanarium, was established in St. Augustine, Florida in 1938. It was initially a large water tank used to exhibit marine mammals for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Habitat Loss
Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby reducing biodiversity and species abundance. Habitat destruction is the leading cause of biodiversity loss. Fragmentation and loss of habitat have become one of the most important topics of research in ecology as they are major threats to the survival of endangered species. Activities such as harvesting natural resources, industrial production and urbanization are human contributions to habitat destruction. Pressure from agriculture is the principal human cause. Some others include mining, logging, trawling, and urban sprawl. Habitat destruction is currently considered the primary cause of species extinction worldwide. Environmental factors can contribute to habitat destruction more indirectly. Geological processes, climate change, intro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endangered Species
An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and invasive species. The International Union for Conservation of Nature (IUCN) Red List lists the global conservation status of many species, and various other agencies assess the status of species within particular areas. Many nations have laws that protect conservation-reliant species which, for example, forbid hunting, restrict land development, or create protected areas. Some endangered species are the target of extensive conservation efforts such as captive breeding and habitat restoration. Human activity is a significant cause in causing some species to become endangered. Conservation status The conservation status of a species indicates the likelihood that it will become extinct. Multiple factors are considered when assessing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Threatened Species
Threatened species are any species (including animals, plants and fungi) which are vulnerable to endangerment in the near future. Species that are threatened are sometimes characterised by the population dynamics measure of '' critical depensation'', a mathematical measure of biomass related to population growth rate. This quantitative metric is one method of evaluating the degree of endangerment. IUCN definition The International Union for Conservation of Nature (IUCN) is the foremost authority on threatened species, and treats threatened species not as a single category, but as a group of three categories, depending on the degree to which they are threatened: *Vulnerable species * Endangered species * Critically endangered species Less-than-threatened categories are near threatened, least concern, and the no longer assigned category of conservation dependent. Species which have not been evaluated (NE), or do not have sufficient data ( data deficient) also are not consid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species Problem
The species problem is the set of questions that arises when biologists attempt to define what a species is. Such a definition is called a species concept; there are at least 26 recognized species concepts. A species concept that works well for sexually reproducing organisms such as birds may be useless for species that reproduce asexually, such as bacteria. The scientific study of the species problem has been called microtaxonomy. One common, but sometimes difficult, question is how best to decide which species an organism belongs to, because reproductively isolated groups may not be readily recognizable, and cryptic species may be present. There is a continuum from ''reproductive isolation'' with no interbreeding, to '' panmixis'', unlimited interbreeding. Populations can move forward or backwards along this continuum, at any point meeting the criteria for one or another species concept, and failing others. Many of the debates on species touch on philosophical issues, such as n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apex Predator
An apex predator, also known as a top predator, is a predator at the top of a food chain, without natural predators of its own. Apex predators are usually defined in terms of trophic dynamics, meaning that they occupy the highest trophic levels. Food chains are often far shorter on land, usually limited to being secondary consumers – for example, wolves prey mostly upon large herbivores (primary consumers), which eat plants (primary producers). The apex predator concept is applied in wildlife management, conservation, and ecotourism. Apex predators have a long evolutionary history, dating at least to the Cambrian period when animals such as ''Anomalocaris'' dominated the seas. Humans have for many centuries interacted with apex predators including the wolf, birds of prey, and cormorants to hunt game animals, birds, and fish respectively. More recently, humans have started interacting with apex predators in new ways. These include interactions via ecotourism, such as with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Data Deficient
A data deficient (DD) species is one which has been categorized by the International Union for Conservation of Nature (IUCN) as offering insufficient information for a proper assessment of conservation status to be made. This does not necessarily indicate that the species has not been extensively studied; but it does indicate that little or no information is available on the abundance and distribution of the species. The IUCN recommends that care be taken to avoid classing species as "data deficient" when the absence of records may indicate dangerously low abundance: "If the range of a taxon is suspected to be relatively circumscribed, if a considerable period of time has elapsed since the last record of the taxon, threatened status may well be justified""The Categories," in IUCN (1983). (see also precautionary principle). See also * IUCN Red List data deficient species * List of data deficient amphibians * IUCN Red List data deficient species (Annelida) * List of data defic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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