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Spyhopping
Cetacean surfacing behaviour is a grouping of movement types that cetaceans make at the water's surface in addition to breathing. Cetaceans have developed and use surface behaviours for many functions such as display, feeding and communication. All regularly observed members of the order Cetacea, including whales, dolphins and porpoises, show a range of surfacing behaviours. Cetacea is usually split into two suborders, Odontoceti and Mysticeti, based on the presence of teeth or baleen plates in adults respectively. However, when considering behaviour, Cetacea can be split into whales (cetaceans more than 10 m long such as sperm and most baleen whales) and dolphins and porpoises (all Odontocetes less than 10 m long including orca tp://ftp.fao.org/docrep/fao/009/t0725e/t0725e10.pdf FAO Marine Mammals of the World, Suborder Odontoceti.) as many behaviours are correlated with size. Although some behaviours such as spyhopping, logging and lobtailing occur in both groups, others such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gray Whale
The gray whale (''Eschrichtius robustus''), also known as the grey whale,Britannica Micro.: v. IV, p. 693. is a baleen whale that migrates between feeding and breeding grounds yearly. It reaches a length of , a weight of up to and lives between 55 and 70 years, although one female was estimated to be 75–80 years of age. The common name of the whale comes from the gray patches and white mottling on its dark skin. Gray whales were once called devil fish because of their fighting behavior when hunted. The gray whale is the sole living species in the genus ''Eschrichtius''. It is the sole living genus in the family (biology), family Eschrichtiidae, however some recent studies classify it as a member of the family Rorqual, Balaenopteridae. This mammal is descended from filter-feeding whales that appeared during the Neogene. The gray whale is distributed in a Northeast Pacific (North American), and an endangered species, endangered Northwest Pacific (Asian), population. North Atla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orca
The orca (''Orcinus orca''), or killer whale, is a toothed whale and the largest member of the oceanic dolphin family. The only extant species in the genus '' Orcinus'', it is recognizable by its black-and-white-patterned body. A cosmopolitan species, it inhabits a wide range of marine environments, from Arctic to Antarctic regions to tropical seas. Orcas are apex predators with a diverse diet. Individual populations often specialize in particular types of prey, including fish, sharks, rays, and marine mammals such as seals, dolphins, and whales. They are highly social, with some populations forming stable matrilineal family groups (pods). Their sophisticated hunting techniques and vocal behaviors, often unique to specific groups and passed down from generation to generation, are considered to be manifestations of animal culture. The International Union for Conservation of Nature (IUCN) lists the orca's conservation status as data deficient as multiple orca types ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jumping Humpback Whale
Jumping or leaping is a form of locomotion or movement in which an organism or non-living (e.g., robotics, robotic) mechanical system propels itself through the air along a ballistic trajectory. Jumping can be distinguished from running, galloping and other gaits where the entire body is temporarily airborne by the relatively long duration of the aerial phase and high angle of initial launch. Some animals, such as the kangaroo, employ jumping (commonly called ''hopping'' in this instance) as their primary form of an Animal locomotion, locomotion, while others, such as frogs, use it only as a means to escape predators. Jumping is also a key feature of various activities and sports, including the long jump, high jump and show jumping. Physics All jumping involves the application of force against a substrate, which in turn generates a reactive force that propels the jumper away from the substrate. Any solid or liquid capable of producing an opposing force can serve as a substra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Minke Whale
The minke whale (), or lesser rorqual, is a species complex of baleen whale. The two species of minke whale are the common (or northern) minke whale and the Antarctic (or southern) minke whale. The minke whale was first described by the Danish naturalist Otto Fabricius in 1780, who assumed it must be an already known species and assigned his specimen to ''Balaena rostrata'', a name given to the northern bottlenose whale by Otto Friedrich Müller in 1776. In 1804, Bernard Germain de Lacépède described a juvenile specimen of ''Balaenoptera acuto-rostrata''. The name is a partial translation of Norwegian language, Norwegian ''minkehval'', possibly after a Norwegian whaler named Meincke, who mistook a northern minke whale for a blue whale. Taxonomy Most modern classifications split the minke whale into two species: *Common minke whale or northern minke whale (''Balaenoptera acutorostrata''), and *Antarctic minke whale or southern minke whale (''Balaenoptera bonaerensis''). Taxono ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Signalling Theory
Within evolutionary biology, signalling theory is a body of theoretical work examining communication between individuals, both within species and across species. The central question is how organisms with conflicting interests, such as in sexual selection, are expected to provide honest signals rather than deceive or cheat, given that the passing on of pleiotropic traits is subject to natural selection, which aims to minimize associated costs without assuming any conscious intent. Mathematical models describe how signalling can contribute to an evolutionarily stable strategy. Signals are given in contexts such as mate selection by females, which subjects the advertising males' signals to selective pressure. Signals thus evolve because they modify the behaviour of the receiver to benefit the signaller. Signals may be honest, conveying information which usefully increases the fitness of the receiver, or dishonest. An individual can cheat by giving a dishonest signal, which m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
West Indies
The West Indies is an island subregion of the Americas, surrounded by the Atlantic Ocean, North Atlantic Ocean and the Caribbean Sea, which comprises 13 independent island country, island countries and 19 dependent territory, dependencies in three archipelagos: the Greater Antilles, the Lesser Antilles, and the Lucayan Archipelago. The subregion includes all the islands in the Antilles, in addition to The Bahamas and the Turks and Caicos Islands, which are in the Atlantic Ocean, North Atlantic Ocean. The term is often interchangeable with "Caribbean", although the latter may also include coastal regions of Central America, Central and South American mainland nations, including Mexico, Belize, Honduras, Panama, Colombia, Venezuela, French Guiana, Guyana, and Suriname, as well as the Atlantic Ocean, Atlantic island nation of Bermuda, all of which are geographically distinct from the three main island groups, but culturally related. Terminology The English term ''Indie'' is deri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Newton Second
The newton-second (also newton second; symbol: N⋅s or N s) is the unit of impulse in the International System of Units (SI). It is dimensionally equivalent to the momentum unit kilogram-metre per second (kg⋅m/s). One newton-second corresponds to a one- newton force applied for one second. :\vec F \cdot t = \Delta m \vec v It can be used to identify the resultant velocity of a mass if a force accelerates the mass for a specific time interval. Definition Momentum is given by the formula: :\mathbf = m \mathbf, * \mathbf is the momentum in newton-seconds (N⋅s) or "kilogram-metres per second" (kg⋅m/s) * m is the mass in kilograms (kg) * \mathbf is the velocity in metres per second (m/s) Examples This table gives the magnitudes of some momenta for various masses and speeds. See also * Power factor *Newton-metre – SI unit of torque In physics and mechanics, torque is the rotational analogue of linear force. It is also referred to as the mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Momentum
In Newtonian mechanics, momentum (: momenta or momentums; more specifically linear momentum or translational momentum) is the product of the mass and velocity of an object. It is a vector quantity, possessing a magnitude and a direction. If is an object's mass and is its velocity (also a vector quantity), then the object's momentum (from Latin '' pellere'' "push, drive") is: \mathbf = m \mathbf. In the International System of Units (SI), the unit of measurement of momentum is the kilogram metre per second (kg⋅m/s), which is dimensionally equivalent to the newton-second. Newton's second law of motion states that the rate of change of a body's momentum is equal to the net force acting on it. Momentum depends on the frame of reference, but in any inertial frame of reference, it is a ''conserved'' quantity, meaning that if a closed system is not affected by external forces, its total momentum does not change. Momentum is also conserved in special relativity (with a mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Chicago Press
The University of Chicago Press is the university press of the University of Chicago, a Private university, private research university in Chicago, Illinois. It is the largest and one of the oldest university presses in the United States. It publishes a wide range of academic titles, including ''The Chicago Manual of Style'', numerous academic journals, and advanced monographs in the academic fields. The press is located just south of the Midway Plaisance on the University of Chicago campus. One of its quasi-independent projects is the BiblioVault, a digital repository for scholarly books. History The University of Chicago Press was founded in 1890, making it one of the oldest continuously operating university presses in the United States. Its first published book was Robert F. Harper's ''Assyrian and Babylonian Letters Belonging to the Kouyunjik Collections of the British Museum''. The book sold five copies during its first two years, but by 1900, the University of Chicago Pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mobula
''Mobula'' is a genus of Batoidea, rays in the family Mobulidae that is found worldwide in tropical and warm, temperate seas. Some authorities consider this to be a subfamily of the Myliobatidae (eagle rays). Their appearance is similar to that of manta rays, which are in the same family, and based on Genetics, genetic and Morphology (biology), morphological evidence, the mantas belong in ''Mobula'' (they are traditionally in their own genus ''Manta''). Species of this genus are often collectively referred to as "devil rays", "flying mobula", or simply "flying rays", due to their propensity for Whale surfacing behaviour, breaching, sometimes in a spectacular manner. These rays gather in groups and leap out of the surface into the air up to around two metres before splashing back into the water. Description Depending on the species, the devil rays can attain widths up to , the largest being second only to the manta rays in size, which can reach . Despite their size, little is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
