BALEEN

BALEEN

https://search.aepiot.com/search.html?q=BALEEN

MultiSearch Tag Explorer

aéPiot

Go

Cetacea thumbnail

Cetacea

Cetacea (; from Latin cetus 'whale', from Ancient Greek κῆτος (kêtos) 'huge fish, sea monster') is an infraorder of aquatic mammals belonging to the order Artiodactyla that includes whales, dolphins and porpoises. Key characteristics are their fully aquatic lifestyle, streamlined body shape, often large size and exclusively carnivorous diet. They propel themselves through the water with powerful up-and-down movements of their tail, which ends in a paddle-like fluke, using their flipper-shaped forelimbs to steer. While the majority of cetaceans live in marine environments, a small number reside solely in brackish or fresh water. Having a cosmopolitan distribution, they can be found in some rivers and all of Earth's oceans, and many species migrate throughout vast ranges with the changing of the seasons. Cetaceans are famous for their high intelligence, complex social behaviour, and the enormous size of some of the group's members. For example, the blue whale reaches a maximum confirmed length of 29.9 meters (98 feet) and a weight of 173 tonnes (190 short tons), making it the largest animal ever known to have existed. There are approximately 90 living species split into two parvorders: the Odontoceti or toothed whales, which contains 75 species including porpoises, dolphins, other predatory whales like the beluga and sperm whale, and the beaked whales and the filter feeding Mysticeti or baleen whales, which contains 15 species and includes the blue whale, the humpback whale and the bowhead whale, among others. Despite their highly modified bodies and carnivorous lifestyle, genetic and fossil evidence places cetaceans within the even-toed ungulates, most closely related to hippopotamus. Cetaceans have been extensively hunted for their meat, blubber and oil by commercial operations. Although the International Whaling Commission has agreed on putting a halt to commercial whaling, whale hunting is still ongoing, either under IWC quotas to assist the subsistence of Arctic native peoples or in the name of scientific research, although a large spectrum of non-lethal methods are now available to study marine mammals in the wild. Cetaceans also face severe environmental hazards from underwater noise pollution, entanglement in ropes and nets, ship strikes, build-up of plastics and heavy metals, and anthropogenic climate change, but how much they are affected varies widely from species to species, from minimally in the case of the southern bottlenose whale to the baiji (Chinese river dolphin) which is considered to be functionally extinct due to human activity.

In connection with: Cetacea

Cetacea

Description combos: the Mysticeti dolphins through halt of halt ungulates toed

Whale thumbnail

Whale

Whales are a widely distributed and diverse group of fully aquatic placental marine mammals. As an informal and colloquial grouping, they correspond to large members of the infraorder Cetacea, i.e. all cetaceans apart from dolphins and porpoises. Dolphins and porpoises may be considered whales from a formal, cladistic perspective. Whales, dolphins and porpoises belong to the order Cetartiodactyla, which consists of even-toed ungulates. Their closest non-cetacean living relatives are the hippopotamuses, from which they and other cetaceans diverged about 54 million years ago. The two parvorders of whales, baleen whales (Mysticeti) and toothed whales (Odontoceti), are thought to have had their last common ancestor around 34 million years ago. Mysticetes include four extant (living) families: Balaenopteridae (the rorquals), Balaenidae (right whales), Cetotheriidae (the pygmy right whale), and Eschrichtiidae (the grey whale). Odontocetes include the Monodontidae (belugas and narwhals), Physeteridae (the sperm whale), Kogiidae (the dwarf and pygmy sperm whale), and Ziphiidae (the beaked whales), as well as the six families of dolphins and porpoises which are not considered whales in the informal sense. Whales are fully aquatic, open-ocean animals: they can feed, mate, give birth, suckle and raise their young at sea. Whales range in size from the 2.6 metres (8.5 ft) and 135 kilograms (298 lb) dwarf sperm whale to the 29.9 metres (98 ft) and 190 tonnes (210 short tons) blue whale, which is the largest known animal that has ever lived. The sperm whale is the largest toothed predator on Earth. Several whale species exhibit sexual dimorphism, in that the females are larger than males. Baleen whales have no teeth; instead, they have plates of baleen, fringe-like structures that enable them to expel the huge mouthfuls of water they take in while retaining the krill and plankton they feed on. Because their heads are enormous—making up as much as 40% of their total body mass—and they have throat pleats that enable them to expand their mouths, they are able to take huge quantities of water into their mouth at a time. Baleen whales also have a well-developed sense of smell. Toothed whales, in contrast, have conical teeth adapted to catching fish or squid. They also have such keen hearing—whether above or below the surface of the water—that some can survive even if they are blind. Some species, such as sperm whales, are particularly well adapted for diving to great depths to catch squid and other favoured prey. Whales evolved from land-living mammals, and must regularly surface to breathe air, although they can remain underwater for long periods of time. Some species, such as the sperm whale, can stay underwater for up to 90 minutes. They have blowholes (modified nostrils) located on top of their heads, through which air is taken in and expelled. They are warm-blooded, and have a layer of fat, or blubber, under the skin. With streamlined fusiform bodies and two limbs that are modified into flippers, whales can travel at speeds of up to 20 knots, though they are not as flexible or agile as seals. Whales produce a great variety of vocalizations, notably the extended songs of the humpback whale. Although whales are widespread, most species prefer the colder waters of the Northern and Southern Hemispheres and migrate to the equator to give birth. Species such as humpbacks and blue whales are capable of travelling thousands of miles without feeding. Males typically mate with multiple females every year, but females only mate every two to three years. Calves are typically born in the spring and summer; females bear all the responsibility for raising them. Mothers in some species fast and nurse their young for one to two years. Once relentlessly hunted for their products, whales are now protected by international law. The North Atlantic right whales nearly became extinct in the twentieth century, with a population low of 450, and the North Pacific grey whale population is ranked Critically Endangered by the IUCN. Besides the threat from whalers, they also face threats from bycatch and marine pollution. The meat, blubber and baleen of whales have traditionally been used by indigenous peoples of the Arctic. Whales have been depicted in various cultures worldwide, notably by the Inuit and the coastal peoples of Vietnam and Ghana, who sometimes hold whale funerals. Whales occasionally feature in literature and film. A famous example is the great white whale in Herman Melville's novel Moby-Dick. Small whales, such as belugas, are sometimes kept in captivity and trained to perform tricks, but breeding success has been poor and the animals often die within a few months of capture. Whale watching has become a form of tourism around the world.

In connection with: Whale

Whale

Description combos: of that 90 on can Arctic in and dolphins

Baleen whale thumbnail

Baleen whale

Baleen whales (), also known as whalebone whales, are marine mammals of the parvorder Mysticeti in the infraorder Cetacea (whales, dolphins and porpoises), which use baleen plates (or "whalebone") in their mouths to sieve plankton from the water. Mysticeti comprises the families Balaenidae (right and bowhead whales), Balaenopteridae (rorquals), Eschrichtiidae (the gray whale) and Cetotheriidae (the pygmy right whale). There are currently 16 species of baleen whales. While cetaceans were historically thought to have descended from mesonychians, molecular evidence instead supports them as a clade of even-toed ungulates (Artiodactyla). Baleen whales split from toothed whales (Odontoceti) around 34 million years ago. Baleen whales range in size from the 6 m (20 ft) and 3,000 kg (6,600 lb) pygmy right whale to the 31 m (102 ft) and 190 t (210 short tons) blue whale, the largest known animal to have ever existed. They are sexually dimorphic. Baleen whales can have streamlined or large bodies, depending on the feeding behavior, and two limbs that are modified into flippers. The fin whale is the fastest baleen whale, recorded swimming at 10 m/s (36 km/h; 22 mph). Baleen whales use their baleen plates to filter out food from the water by either lunge-feeding or skim-feeding. Baleen whales have fused neck vertebrae, and are unable to turn their heads at all. Baleen whales have two blowholes. Some species are well adapted for diving to great depths. They have a layer of fat, or blubber, under the skin to keep warm in the cold water. Although baleen whales are widespread, most species prefer the colder waters of the Arctic and Antarctic. Gray whales are specialized for feeding on bottom-dwelling crustaceans. Rorquals are specialized at lunge-feeding, and have a streamlined body to reduce drag while accelerating. Right whales skim-feed, meaning they use their enlarged head to effectively take in a large amount of water and sieve the slow-moving prey. Males typically mate with more than one female (polygyny), although the degree of polygyny varies with the species. Male strategies for reproductive success vary between performing ritual displays (whale song) or lek mating. Calves are typically born in the winter and spring months and females bear all the responsibility for raising them. Mothers fast for a relatively long period of time over the period of migration, which varies between species. Baleen whales produce a number of infrasonic vocalizations, notably the songs of the humpback whale. The meat, blubber, baleen, and oil of baleen whales have traditionally been used by the indigenous peoples of the Arctic. Once relentlessly hunted by commercial industries for these products, cetaceans are now protected by international law. These protections have allowed their numbers to recover. However, the North Atlantic right whale is ranked critically endangered by the International Union for Conservation of Nature. Besides hunting, baleen whales also face threats from marine pollution and ocean acidification. It has been speculated that man-made sonar results in strandings. They have rarely been kept in captivity, and this has only been attempted with juveniles or members of one of the smallest species.

In connection with: Baleen whale

Baleen

whale

Title combos: whale Baleen

Description combos: lunge captivity swimming They are either than whales from

Baleen thumbnail

Baleen

Baleen is a filter-feeding system inside the mouths of baleen whales. To use baleen, the whale first opens its mouth underwater to take in water. The whale then pushes the water out, and animals such as krill are filtered by the baleen and remain as a food source for the whale. Baleen is similar to bristles and consists of keratin, the same substance found in human fingernails, skin and hair. Baleen is a skin derivative. Some whales, such as the bowhead whale, have baleen of differing lengths. Other whales, such as the gray whale, only use one side of their baleen. These baleen bristles are arranged in plates across the upper jaw of whales. Depending on the species, a baleen plate can be 0.5 to 3.5 m (1.6 to 11.5 ft) long, and weigh up to 90 kg (200 lb). Its hairy fringes are called baleen hair or whalebone hair. They are also called baleen bristles, which in sei whales are highly calcified, with calcification functioning to increase their stiffness. Baleen plates are broader at the gumline (base). The plates have been compared to sieves or Venetian blinds. As a material for various human uses, baleen is usually called whalebone, which is a misnomer.

In connection with: Baleen

Baleen

Description combos: highly bristles in functioning baleen in its Baleen then

Filter feeder thumbnail

Filter feeder

Filter feeders are aquatic animals that acquire nutrients by feeding on organic matters, food particles or smaller organisms (bacteria, microalgae and zooplanktons) suspended in water, typically by having the water pass over or through a specialized filtering organ that sieves out and/or traps solids. Filter feeders can play an important role in condensing biomass and removing excess nutrients (such as nitrogen and phosphate) from the local waterbody, and are therefore considered water-cleaning ecosystem engineers. They are also important in bioaccumulation and, as a result, as indicator organisms. Filter feeders can be sessile, planktonic, nektonic or even neustonic (in the case of the buoy barnacle) depending on the species and the niches they have evolved to occupy. Extant species that rely on such method of feeding encompass numerous phyla, including poriferans (sponges), cnidarians (jellyfish, sea pens and corals), arthropods (krill, mysids and barnacles), molluscs (bivalves, such as clams, scallops and oysters), echinoderms (sea lilies) and chordates (lancelets, sea squirts and salps, as well as many marine vertebrates such as most species of forage fish, American paddlefish, silver and bighead carps, baleen whales, manta ray and three species of sharks—the whale shark, basking shark and megamouth shark). Some water birds such as flamingos and certain duck species, though predominantly terrestrial, are also filter feeders when foraging.

In connection with: Filter feeder

Filter

feeder

Title combos: Filter feeder

Description combos: particles they silver or pass organisms and carps feeders

Evolution of cetaceans thumbnail

Evolution of cetaceans

The evolution of cetaceans is thought to have begun in the Indian subcontinent from even-toed ungulates (Artiodactyla) 50 million years ago (mya) and to have proceeded over a period of at least 15 million years. Cetaceans are fully aquatic mammals belonging to the order Artiodactyla and branched off from other artiodactyls around 50 mya. Cetaceans are thought to have evolved during the Eocene (56-34 mya), the second epoch of the present-extending Cenozoic Era. Molecular and morphological analyses suggest Cetacea share a relatively recent closest common ancestor with hippopotamuses and that they are sister groups. Being mammals, they surface to breathe air; they have five finger bones (even-toed) in their fins; they nurse their young; and, despite their fully aquatic life style, they retain many skeletal features from their terrestrial ancestors. Research conducted in the late 1970s in Pakistan revealed several stages in the transition of cetaceans from land to sea. The two modern parvorders of cetaceans – Mysticeti (baleen whales) and Odontoceti (toothed whales) – are thought to have separated from each other around 28–33 mya in a second cetacean radiation, the first occurring with the archaeocetes. The adaptation of animal echolocation in toothed whales distinguishes them from fully aquatic archaeocetes and early baleen whales. The presence of baleen in baleen whales occurred gradually, with earlier varieties having very little baleen, and their size is linked to baleen dependence (and subsequent increase in filter feeding).

In connection with: Evolution of cetaceans

Evolution

of

cetaceans

Title combos: of Evolution cetaceans of Evolution

Description combos: subcontinent aquatic in with adaptation of adaptation style aquatic

Mount Baleen thumbnail

Mount Baleen

Mount Baleen (65°36′S 62°12′W) is a prominent peak of 910 m and of pyramidal shape when viewed from Larsen Ice Shelf, standing in Padesh Ridge between Rachel and Starbuck Glaciers in Aristotle Mountains on the east coast of Graham Land. The naming by United Kingdom Antarctic Place-Names Committee (UK-APC) is one in a group in this vicinity that reflects a whaling theme. Baleen whales are distinguished by the presence of a sieve of horny baleen (whalebone) plates suspended from the upper jaw, and by the absence of teeth. This article incorporates public domain material from "Mount Baleen". Geographic Names Information System. United States Geological Survey.

In connection with: Mount Baleen

Mount

Baleen

Title combos: Baleen Mount

Description combos: Names one in of coast Information domain theme Baleen

Quick Access

Tag Explorer


Partajare

Discover Fresh Ideas in the Universe of aéPiot

MultiSearch | Search | Tag Explorer

SHEET MUSIC | DIGITAL DOWNLOADS

News | LIVE TV

INSTAPAPER

© aéPiot - MultiSearch Tag Explorer. All rights reserved.

Hosted by HOSTGATE

Headlines World

aéPiot.com

aéPiot.ro

allGraph




Report Page