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Hourglass Dolphin
The hourglass dolphin (''Lagenorhynchus cruciger'') is a small dolphin in the family Delphinidae that inhabits offshore Antarctic and sub-Antarctic waters. It is commonly seen from ships crossing the Drake Passage but has a circumpolar distribution. The species was identified as a new species by Jean René Constant Quoy and Joseph Paul Gaimard in 1824 from a drawing made in the South Pacific in 1820. It is the only cetacean to have been widely accepted as a species solely on witness accounts. Description The hourglass dolphin is colored black on top and white on the belly, with white patches on the sides and sometimes variations of dark grey. For this reason, it was colloquially known by whalers as a "sea cow" (although it does not belong to the taxonomic order Sirenia) or "sea skunk". Each flank has a white patch at the front, above the beak, eye and flipper, and a second patch at the rear. These two patches are connected by a thin white strip, creating, loosely speaking, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drake Passage
The Drake Passage is the body of water between South America's Cape Horn, Chile, Argentina, and the South Shetland Islands of Antarctica. It connects the southwestern part of the Atlantic Ocean (Scotia Sea) with the southeastern part of the Pacific Ocean and extends into the Southern Ocean. The passage is named after the 16th-century English explorer and privateer Sir Francis Drake. The Drake Passage is considered one of the most treacherous voyages for ships to make. The Antarctic Circumpolar Current, which runs through it, meets no resistance from any landmass, and waves top , giving it a reputation for being "the most powerful convergence of seas". As the Drake Passage is the narrowest passage (choke point) around Antarctica, its existence and shape strongly influence the circulation of water around Antarctica and the global oceanic circulation, as well as the global climate. The bathymetry of the Drake Passage plays an important role in the global mixing of oceanic water ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Zealand
New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of island countries, sixth-largest island country by area and lies east of Australia across the Tasman Sea and south of the islands of New Caledonia, Fiji, and Tonga. The Geography of New Zealand, country's varied topography and sharp mountain peaks, including the Southern Alps (), owe much to tectonic uplift and volcanic eruptions. Capital of New Zealand, New Zealand's capital city is Wellington, and its most populous city is Auckland. The islands of New Zealand were the last large habitable land to be settled by humans. Between about 1280 and 1350, Polynesians began to settle in the islands and subsequently developed a distinctive Māori culture. In 1642, the Dutch explorer Abel Tasman became the first European to sight and record New Zealand. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atlantic White-sided Dolphin
The Atlantic white-sided dolphin (''Lagenorhynchus acutus'') is a distinctively coloured dolphin found in the cool to temperate waters of the North Atlantic Ocean. Description The Atlantic white-sided dolphin is a relatively small dolphin. At birth, calves measure just over a meter long; adult males grow to about , and females to about , weighing between 180–230 kg (400- 510 lb) once fully grown. Females reach sexual maturity between the ages of 6 and 12 years, and males between 7 and 11 years old. The gestation period is 11 months and lactation lasts for about 18 months — both typical figures for dolphins. Atlantic white-sided dolphins are known to live for at least 17 years. The key distinguishing feature is the dolphin's coloration—a white to pale-yellow patch is found behind the dorsal fin on both sides of the body. The white-sided dolphin's color variations are unique amongst the standard hues of white, grey, black and blue seen on other pelagic cetaceans. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Squid
A squid (: squid) is a mollusc with an elongated soft body, large eyes, eight cephalopod limb, arms, and two tentacles in the orders Myopsida, Oegopsida, and Bathyteuthida (though many other molluscs within the broader Neocoleoidea are also called ''squid'' despite not strictly fitting these criteria). Like all other cephalopods, squid have a distinct head, Symmetry (biology)#Bilateral symmetry, bilateral symmetry, and a mantle (mollusc), mantle. They are mainly soft-bodied, like octopuses, but have a small internal skeleton in the form of a rod-like gladius (cephalopod), gladius or pen, made of chitin. Squid diverged from other cephalopods during the Jurassic and occupy a similar Ecological niche, role to teleost fish as open-water predators of similar size and behaviour. They play an important role in the open-water food web. The two long tentacles are used to grab prey and the eight arms to hold and control it. The beak then cuts the food into suitable size chunks for swal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polychaete Worms
Polychaeta () is a paraphyletic class of generally marine annelid worms, commonly called bristle worms or polychaetes (). Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are made of chitin. More than 10,000 species are described in this class. Common representatives include the lugworm (''Arenicola marina'') and the sandworm or clam worm ''Alitta''. Polychaetes as a class are robust and widespread, with species that live in the coldest ocean temperatures of the abyssal plain, to forms which tolerate the extremely high temperatures near hydrothermal vents. Polychaetes occur throughout the Earth's oceans at all depths, from forms that live as plankton near the surface, to a 2- to 3-cm specimen (still unclassified) observed by the robot ocean probe ''Nereus'' at the bottom of the Challenger Deep, the deepest known spot in the Earth's oceans. Only 168 species (less than 2% of all polychaetes) are known from fresh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mantis Shrimp
Mantis shrimp are carnivorous marine crustaceans of the order Stomatopoda (). Stomatopods branched off from other members of the class Malacostraca around 400 million years ago, with more than 520 extant species of mantis shrimp known. All living species are in the suborder Unipeltata, which arose around 250 million years ago. They are among the most important predators in many shallow, tropical and subtropical marine habitats. Despite being common in their habitats, they are poorly understood, as many species spend most of their lives sheltering in burrows and holes. Dubbed "sea locusts" by ancient Assyrians, "prawn killers" in Australia, and now sometimes referred to as "thumb splitters" due to their ability to inflict painful wounds if handled incautiously, mantis shrimp possess powerful raptorial appendages that are used to attack and kill prey either by spearing, stunning, or dismembering; the shape of these appendages are often used to classify them into groups: extant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arnoux's Beaked Whale
Arnoux's beaked whale (''Berardius arnuxii''), also called the southern four-toothed whale, southern beaked whale, New Zealand beaked whale, southern giant bottlenose whale and southern porpoise whale is one of the species of ''Berardius''. Arnoux's and Baird's beaked whales are so similar that researchers debated whether or not they are simply two populations of the same species, until genetic evidence and their wide geographical separation led them to be classified as separate. Little is known about their behavior due to infrequent encounters with live individuals. Etymology Named Berardius arnuxii in 1851 for the French surgeon, M. Arnoux, who presented the skull to the Paris Museum of Natural History in 1846. Physical description Arnoux's and Baird's beaked whales, have very similar features and would be indistinguishable at sea if they did not exist in disjoint locations. Both whales reach similar sizes, have bulbous melons, and long prominent beaks. Their lower jaw is longe ... [...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] |
Southern Bottlenose Whale
The southern bottlenose whale (''Hyperoodon planifrons'') is a species of whale, in the ziphiid family, one of two members of the genus ''Hyperoodon''. Seldom observed, the southern bottlenose whale is resident in Antarctic waters. The species was first described by English zoologist William Henry Flower in 1882, based on a water-worn skull from Lewis Island, in the Dampier Archipelago, Western Australia. They live in deep ocean waters over 1000 meters. Taxonomy No subspecies of the southern bottlenose whale are named (Mead 1989). A mtDNA study of two southern bottlenose whales from different regions of New Zealand was conducted and found that mtDNA differed 4.13%, which is higher than the interspecific variation of 2% found in other beaked whales (Dalebout et al., 1998). Intraspecific coloration variation may be due to genetics; however, variation based on geographical location is not ruled out (Van Waerebeek et al., 2005). Description The southern bottlenose whale measures 7 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bow Riding
Cetacean intelligence is the overall intelligence and derived cognitive ability of aquatic mammals belonging in the infraorder Cetacea (cetaceans), including baleen whales, porpoises, and dolphins. In 2014, a study found that the long-finned pilot whale has more neocortical neurons than any other mammal, including humans, examined to date. Brain Size Brain size was previously considered a major indicator of the intelligence of an animal. However, many other factors also affect intelligence, and recent discoveries concerning bird intelligence have called into question the influence of brain size. Since most of the brain is used for maintaining bodily functions, greater ratios of brain to body mass may increase the amount of brain mass available for more complex cognitive tasks. Allometric analysis indicates that in general, mammalian brain size scales at approximately the or exponent of body mass. Comparison of actual brain size with the size expected from allometry provides an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fin Whale
The fin whale (''Balaenoptera physalus''), also known as the finback whale or common rorqual, is a species of baleen whale and the second-longest cetacean after the blue whale. The biggest individual reportedly measured in length, with a maximum recorded weight of . The fin whale's body is long, slender and brownish-gray in color, with a paler underside to appear less conspicuous from below (countershading). At least two recognized subspecies exist, one in the North Atlantic and one across the Southern Hemisphere. It is found in all the major oceans, from polar to tropical waters, though it is absent only from waters close to the pack ice at the poles and relatively small areas of water away from the open ocean. The highest population density occurs in temperate and cool waters. Its prey mainly consists of smaller schooling fish, small squid, or crustaceans, including copepods and krill. Mating takes place in temperate, low-latitude seas during the win ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Minke Whales
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 ''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''). Taxonomists further ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
