|
Many-toothed Blackfish
The melon-headed whale (''Peponocephala electra''), also known less commonly as the electra dolphin, little killer whale, or many-toothed blackfish, is a toothed whale of the oceanic dolphin family (Delphinidae). The common name is derived from the head shape. Melon-headed whales are widely distributed throughout deep tropical and subtropical waters worldwide, but they are rarely encountered at sea. They are found near shore mostly around oceanic islands, such as Hawaii, French Polynesia, and the Philippines. Taxonomy The melon-headed whale is the only member of the genus ''Peponocephala''. First recorded from a specimen collected in Hawaiʻi in 1841, the species was originally described as a member of the dolphin family and named ''Lagenorhynchus electra'' by John Edward Gray in 1846. The melon-headed whale was later determined to be sufficiently distinct from other ''Lagenorhynchus'' species to be accorded its own genus. A member of the subfamily Globicephalinae, melon-headed wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Edward Gray
John Edward Gray, FRS (12 February 1800 – 7 March 1875) was a British zoologist. He was the elder brother of zoologist George Robert Gray and son of the pharmacologist and botanist Samuel Frederick Gray (1766–1828). The same is used for a zoological name. Gray was keeper of zoology at the British Museum in London from 1840 until Christmas 1874, before the natural history holdings were split off to the Natural History Museum. He published several catalogues of the museum collections that included comprehensive discussions of animal groups and descriptions of new species. He improved the zoological collections to make them amongst the best in the world. Biography Gray was born in Walsall, but his family soon moved to London, where Gray studied medicine. He assisted his father in writing ''The Natural Arrangement of British Plants'' (1821). After being blackballed by the Linnean Society of London, Gray shifted his interest from botany to zoology. He began his zoologica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pelagic
The pelagic zone consists of the water column of the open ocean, and can be further divided into regions by depth (as illustrated on the right). The word ''pelagic'' is derived . The pelagic zone can be thought of as an imaginary cylinder or water column between the surface of the sea and the bottom. Conditions in the water column change with depth: pressure increases; temperature and light decrease; salinity, oxygen, micronutrients (such as iron, magnesium and calcium) all change. Marine life is affected by bathymetry (underwater topography) such as the seafloor, shoreline, or a submarine seamount, as well as by proximity to the boundary between the ocean and the atmosphere at the ocean surface, which brings light for photosynthesis, predation from above, and wind stirring up waves and setting currents in motion. The pelagic zone refers to the open, free waters away from the shore, where marine life can swim freely in any direction unhindered by topographical constraints. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cookie Cutter Shark
The cookiecutter shark (''Isistius brasiliensis''), also called the cigar shark, is a species of small squaliform shark in the family Dalatiidae. This shark occurs in warm, oceanic waters worldwide, particularly near islands, and has been recorded as deep as . It migrates vertically up to every day, approaching the surface at dusk and descending with the dawn. Reaching only in length, the cookiecutter shark has a long, cylindrical body with a short, blunt snout, large eyes, two tiny spineless dorsal fins, and a large caudal fin. It is dark brown, with light-emitting photophores covering its underside except for a dark "collar" around its throat and gill slits. The name "cookiecutter shark" refers to its feeding habit of gouging round plugs, as if cut out with a cookie cutter, out of larger animals. Marks made by cookiecutter sharks have been found on a wide variety of marine mammals and fishes, as well as on submarines, undersea cables, and even human bodies. It also consume ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pantropical Spotted Dolphin
The pantropical spotted dolphin (''Stenella attenuata'') is a species of dolphin found in all the world's temperate and tropical oceans. The species was beginning to come under threat due to the killing of millions of individuals in tuna purse seines. In the 1980s, the rise of "dolphin-friendly" tuna capture methods saved millions of the species in the eastern Pacific Ocean and it is now one of the most abundant dolphin species in the world. Taxonomy The species was first described by John Gray in 1846. Gray's initial analysis included the Atlantic spotted dolphin in this species. They are now regarded as separate. Both the genus and specific names come from Latin words meaning thin or thinning. Two subspecies of the pantropical spotted dolphin are recognized: :''S. a. attenuata'' or offshore pantropical spotted dolphin, found worldwide in tropical waters :''S. a. graffmani'' or coastal pantropical spotted dolphin, found in coastal waters in the eastern tropical Pacific Anoth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rough-toothed Dolphin
The rough-toothed dolphin (''Steno bredanensis'') is a species of dolphin that can be found in deep warm and tropical waters around the world. The species was first described by Georges Cuvier in 1823. The genus name ''Steno'', of which this species is the monotypic taxon, only member, comes from the Greek language, Greek for 'narrow', referring to the animal's beak — which is a diagnostic characteristic of the species. The specific name honours Jacob Gijsbertus Samuël van Breda, van Breda, who studied Cuvier's writings. There are no recognised subspecies. Taxonomy This species was formerly classified in the now-defunct subfamily Stenoninae, but more recent evidence has found that, despite its prominent bill, it in fact belongs with the blunt-nosed dolphins in the subfamily Globicephalinae. Description The rough-toothed dolphin is a relatively large species, with adults ranging from in length, and weighing between ; males are larger than females. Its most visible cha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bottlenose Dolphin
Bottlenose dolphins are aquatic mammals in the genus ''Tursiops.'' They are common, cosmopolitan members of the family Delphinidae, the family of oceanic dolphins. Molecular studies show the genus definitively contains two species: the common bottlenose dolphin (''Tursiops truncatus'') and the Indo-Pacific bottlenose dolphin (''Tursiops aduncus''). Others, like the Burrunan dolphin (''Tursiops (aduncus) australis''), may be alternately considered their own species or be subspecies of ''T. aduncus''. Bottlenose dolphins inhabit warm and temperate seas worldwide, being found everywhere except for the Arctic and Antarctic Circle regions. Their name derives from the Latin ''tursio'' (dolphin) and ''truncatus'' for their characteristic truncated teeth. Numerous investigations of bottlenose dolphin intelligence have been conducted, examining mimicry, use of artificial language, object categorization, and self-recognition. They can use tools (sponging; using marine sponges to forage ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fraser's Dolphin
Fraser's dolphin or the Sarawak dolphin (''Lagenodelphis hosei'') is a cetacean in the family Delphinidae found in deep waters in the Pacific Ocean and to a lesser extent in the Indian and Atlantic Oceans. Taxonomy ''Lagenodelphis hosei'' is species of the delphinid family, distinguished from other dolphins as a monotypic genus, ''Lagenodelphis''. In 1895, Charles E. Hose found a skull on a beach in Sarawak, Borneo. He donated it to the British Museum. The skull remained unstudied until 1956 when Francis Fraser examined it and concluded that it was similar to species in both the genera ''Lagenorhynchus'' and ''Delphinus'' but not the same as either. A new genus was created by simply merging these two names together. The specific name is given in Hose's honour. It wasn't until 1971 that the whole body of a Fraser's dolphin, as it was by then becoming known, was discovered. At that time washed-up specimens were found on Cocos Island in the eastern Pacific, in South Australia and i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinner Dolphin
The spinner dolphin (''Stenella longirostris'') is a small dolphin found in off-shore tropical waters around the world. It is famous for its acrobatic displays in which it rotates around its longitudinal axis as it leaps through the air. It is a member of the family Delphinidae of toothed whales. Taxonomy The spinner dolphin is sometimes referred to as the long-snouted dolphin, particularly in older texts, to distinguish it from the similar Clymene dolphin, which is often called the short-snouted spinner dolphin. The species was described by John Gray in 1828. The four named subspecies are: *Eastern spinner dolphin (''S. l. orientalis''), from the tropical eastern Pacific. *Central American or Costa Rican spinner dolphin (''S. l. centroamericana''), also found in the tropical eastern Pacific. *Gray's or Hawaiian spinner dolphin (''S. l. longirostris''), from the central Pacific Ocean around Hawaii but represents a mixture of broadly similar subtypes found worldwide. *Dwarf spin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animal Echolocation
Echolocation, also called bio sonar, is a biological sonar used by several animal species. Echolocating animals emit calls out to the environment and listen to the echoes of those calls that return from various objects near them. They use these echoes to locate and identify the objects. Echolocation is used for navigation, foraging, and hunting in various environments. Echolocating animals include some mammals (most notably Laurasiatheria) and a few birds, especially some bat species and odontocetes (toothed whales and dolphins), but also in simpler forms in other groups such as shrews, and two cave-dwelling bird groups, the so-called cave swiftlets in the genus ''Aerodramus'' (formerly ''Collocalia'') and the unrelated oilbird ''Steatornis caripensis''. Early research The term ''echolocation'' was coined in 1938 by the American zoologist Donald Griffin, who, with Robert Galambos, first demonstrated the phenomenon in bats. As Griffin described in his book, the 18th century I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Matrilineality
Matrilineality is the tracing of kinship through the female line. It may also correlate with a social system in which each person is identified with their matriline – their mother's lineage – and which can involve the inheritance of property and/or titles. A matriline is a line of descent from a female ancestor to a descendant (of either sex) in which the individuals in all intervening generations are mothersin other words, a "mother line". In a matrilineal descent system, an individual is considered to belong to the same descent group as their mother. This ancient matrilineal descent pattern is in contrast to the currently more popular pattern of patrilineal descent from which a family name is usually derived. The ''matriline'' of historical nobility was also called their enatic or uterine ancestry, corresponding to the patrilineal or "agnatic" ancestry. Early human kinship In the late 19th century, almost all prehistorians and anthropologists believed, followi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diel Vertical Migration
Diel vertical migration (DVM), also known as diurnal vertical migration, is a pattern of movement used by some organisms, such as copepods, living in the ocean and in lakes. The word ''diel'' comes from the Latin ''dies'' day, and means a 24-hour period. The migration occurs when organisms move up to the uppermost layer of the sea at night and return to the bottom of the daylight zone of the oceans or to the dense, bottom layer of lakes during the day. It is important to the functioning of deep-sea food webs and the biologically driven sequestration of carbon. In terms of biomass, it is the largest synchronous migration in the world. It is not restricted to any one taxon as examples are known from crustaceans (copepods), molluscs (squid), and ray-finned fishes (trout). The phenomenon may be advantageous for a number of reasons, most typically to access food and avoid predators. It is triggered by various stimuli, the most prominent being response to changes in light i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
_(6206904718).jpg "Click for more on -> Many-toothed Blackfish")
