63-458: (Redirected from Black Whale ) Black whale is a vernacular name for certain whales . It may be encountered as a colloquial or as a quasi-scientific term. In whaling jargon, the sperm whale ( Physeter macrocephalus ) of the Physeteridae was sometimes known as the "black whale" "Black whale" is a name for a presumed right whale species in
126-516: A spermaceti organ . Other phylogenetic research raises further questions over a potential relationship between kogiids and Ziphiidae . Other questions exist regarding the high relatedness in mitochondrial DNA between Platanista and kogiids. Fossil evidence is limited for this family, which potentially limits an understanding of their relationship to other extant cetaceans. Researchers have proposed that K. sima may represent at least two genetically unique species, and further genetic research
189-408: A tapetum lucidum ; these adaptations allow for large amounts of light to pass through the eye and, therefore, a very clear image of the surrounding area. They also have glands on the eyelids and outer corneal layer that act as protection for the cornea. The olfactory lobes are absent in toothed whales, suggesting that they have no sense of smell. Some whales, such as the bowhead whale , possess
252-485: A vomeronasal organ , which does mean that they can "sniff out" krill. Whales are not thought to have a good sense of taste, as their taste buds are atrophied or missing altogether. However, some toothed whales have preferences between different kinds of fish, indicating some sort of attachment to taste. The presence of the Jacobson's organ indicates that whales can smell food once inside their mouth, which might be similar to
315-733: A different reason for it, for example, the killer whale was named "Ballena asesina" 'killer whale' by Spanish sailors. The term "Great Whales" covers those currently regulated by the International Whaling Commission : the Odontoceti family Physeteridae (sperm whales); and the Mysticeti families Balaenidae (right and bowhead whales), Eschrichtiidae (grey whales), and some of the Balaenopteridae (Minke, Bryde's, Sei, Blue and Fin; not Eden's and Omura's whales). The whales are part of
378-570: A form of tourism around the world. The word "whale" comes from the Old English hwæl , from Proto-Germanic *hwalaz , from Proto-Indo-European *(s)kwal-o- , meaning "large sea fish". The Proto-Germanic *hwalaz is also the source of Old Saxon hwal , Old Norse hvalr , hvalfiskr , Swedish val , Middle Dutch wal , walvisc , Dutch walvis , Old High German wal , and German Wal . Other archaic English forms include wal, wale, whal, whalle, whaille, wheal , etc. The term "whale"
441-682: 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
504-420: A small bulge sitting on top of its skull, whereas a sperm whale's head is filled up mainly with the melon. The whale eye is relatively small for its size, yet they do retain a good degree of eyesight. As well as this, the eyes of a whale are placed on the sides of its head, so their vision consists of two fields, rather than a binocular view like humans have. When belugas surface, their lens and cornea correct
567-456: A strong desire on behalf of the whales to communicate with humans, as whales have a very different vocal mechanism, so imitating human speech likely takes considerable effort. Whales emit two distinct kinds of acoustic signals, which are called whistles and clicks: Clicks are quick broadband burst pulses, used for sonar , although some lower-frequency broadband vocalizations may serve a non-echolocative purpose such as communication; for example,
630-514: A technique known as suction feeding, and their diet primarily consists of squid. Pygmy sperm whales are able to eat larger prey than dwarf sperm whales, although their diet as a whole is relatively similar. They have also been observed using echolocation to find their prey, and their hearing places them in the "Very High Frequency" group of cetaceans that can hear well above 100 kHz. Most observations of Kogia have come from individuals tangled in fishing line or stranded individuals. There
693-429: A two- to three-chambered stomach that is similar in structure to those of terrestrial carnivores. Mysticetes contain a proventriculus as an extension of the oesophagus ; this contains stones that grind up food. They also have fundic and pyloric chambers. Whales have two flippers on the front, and a tail fin. These flippers contain four digits. Although whales do not possess fully developed hind limbs, some, such as
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#1732876743454756-429: A unique system of organs to produce sound, including a bagpipe -like structure to produce sound and an amplifying horn. Kogiidae have a modified colon which works as an " ink sac ", storing liquid red feces. They are able to release over three gallons of this fecal "ink" to confuse or discourage predators. Kogiidae are believed to be cosmopolitan species , inhabiting all oceans except polar waters, remaining between
819-470: Is a family comprising at least two extant species of Cetacea, the pygmy ( Kogia breviceps) and dwarf ( K. sima) sperm whales . As their common names suggest, they somewhat resemble sperm whales , with squared heads and small lower jaws, but are much smaller, with much shorter skulls and more notable dorsal fins than sperm whales. Kogiids are also characterized by a "false gill slit" behind their eyes. A number of extinct genera have been named. There
882-515: Is characterized by the presence of baleen, a sieve-like structure in the upper jaw made of keratin , which it uses to filter plankton , among others, from the water. Odontocetes (toothed whales) are characterized by bearing sharp teeth for hunting, as opposed to their counterparts' baleen. Cetaceans and artiodactyls now are classified under the order Cetartiodactyla , often still referred to as Artiodactyla, which includes both whales and hippopotamuses . The hippopotamus and pygmy hippopotamus are
945-477: Is different from Wikidata All article disambiguation pages All disambiguation pages Animal common name disambiguation pages 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
1008-437: Is helpful for a 100-ton whale), protection to some extent as predators would have a hard time getting through a thick layer of fat, and energy for fasting when migrating to the equator; the primary usage for blubber is insulation from the harsh climate. It can constitute as much as 50% of a whale's body weight. Calves are born with only a thin layer of blubber, but some species compensate for this with thick lanugos. Whales have
1071-406: Is home to elongated spindle neurons that, prior to 2007, were known only in hominids. In humans, these cells are involved in social conduct, emotions, judgement, and theory of mind. Whale spindle neurons are found in areas of the brain that are homologous to where they are found in humans, suggesting that they perform a similar function. Brain size was previously considered a major indicator of
1134-442: Is in their feeding adaptations and subsequent behaviour. Balaenopterids are the rorquals. These animals, along with the cetotheriids, rely on their throat pleats to gulp large amounts of water while feeding. The throat pleats extend from the mouth to the navel and allow the mouth to expand to a large volume for more efficient capture of the small animals they feed on. Balaenopterids consist of two genera and eight species. Balaenids are
1197-419: Is needed to determine the real number of extant species of Kogiidae . ORDER ARTIODACTYLA Kogiid skulls are characterized by a very short rostrum , the smallest among extant cetaceans, as well as high levels of asymmetry, which is expected among odontocetes . Kogiid skulls have the most blunt mandible among extant cetaceans as well. Extant kogiidae also show relatively high encephalization quotient ,
1260-404: Is some amount of uncertainty over if Kogiidae belongs in the sperm whale family . Research still suggests a close relationship between Kogiidae and sperm whales using mitochondrial DNA , which supports Kogiidae as part of the sperm whale family. This relationship is supported by similarities of the anatomical structures in the head, responsible for sound production, in particular the presence of
1323-438: Is sometimes used interchangeably with dolphins and porpoises , acting as a synonym for Cetacea . Six species of dolphins have the word "whale" in their name, collectively known as blackfish: the orca , or killer whale, the melon-headed whale , the pygmy killer whale , the false killer whale , and the two species of pilot whales , all of which are classified under the family Delphinidae (oceanic dolphins). Each species has
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#17328767434541386-442: 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
1449-401: Is then expelled through the baleen, leaving their prey trapped inside. This is an efficient method of hunting, in which the whale has no major competitors. Odontocetes are known as toothed whales; they have teeth and only one blowhole. They rely on their well-developed sonar to find their way in the water. Toothed whales send out ultrasonic clicks using the melon . Sound waves travel through
1512-562: The Indohyus , an extinct chevrotain -like ungulate, from which they split approximately 48 million years ago. Primitive cetaceans, or archaeocetes , first took to the sea approximately 49 million years ago and became fully aquatic 5–10 million years later. What defines an archaeocete is the presence of anatomical features exclusive to cetaceans, alongside other primitive features not found in modern cetaceans, such as visible legs or asymmetrical teeth. Their features became adapted for living in
1575-523: The Balaenidae . It was also called "northern right whale" but has more recently been separated into: North Atlantic right whale ( Eubalaena glacialis ) North Pacific right whale ( Eubalaena japonica ) The Black Whale , a 1934 German film Im schwarzen Walfisch zu Askalon (German for In the Black Whale of Ascalon ), a commercium song by Joseph Victor von Scheffel. Topics referred to by
1638-468: 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
1701-541: The beluga and the narwhal . They both reside in the frigid arctic and both have large amounts of blubber. Belugas, being white, hunt in large pods near the surface and around pack ice, their coloration acting as camouflage. Narwhals, being black, hunt in large pods in the aphotic zone, but their underbelly still remains white to remain camouflaged when something is looking directly up or down at them. They have no dorsal fin to prevent collision with pack ice. Physeterids and Kogiids consist of sperm whales . Sperm whales consist
1764-433: The blowhole , forming an upward, steamy spout, followed by inhaling fresh air into the lungs; a humpback whale's lungs can hold about 5,000 litres (1,300 US gal) of air. Spout shapes differ among species, which facilitates identification. All whales have a thick layer of blubber . In species that live near the poles, the blubber can be as thick as 11 inches (28 cm). This blubber can help with buoyancy (which
1827-405: The marine environment . Major anatomical changes included their hearing set-up that channeled vibrations from the jaw to the earbone ( Ambulocetus 49 mya ), a streamlined body and the growth of flukes on the tail ( Protocetus 43 mya), the migration of the nostrils toward the top of the cranium ( blowholes ), and the modification of the forelimbs into flippers ( Basilosaurus 35 mya), and
1890-417: The photic zone . Ziphiids consist of 22 species of beaked whale . These vary from size, to coloration, to distribution, but they all share a similar hunting style. They use a suction technique, aided by a pair of grooves on the underside of their head, not unlike the throat pleats on the rorquals , to feed. As a formal clade (a group which does not exclude any descendant taxon ), odontocetes also contains
1953-424: The porpoises (Phocoenidae) and four or five living families of dolphins: oceanic dolphins ( Delphinidae ), South Asian river dolphins ( Platanistidae ), the possibly extinct Yangtze River dolphin ( Lipotidae ), South American river dolphins ( Iniidae ), and La Plata dolphin (Pontoporiidae). Whales are descendants of land-dwelling mammals of the artiodactyl order (even-toed ungulates). They are related to
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2016-484: 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
2079-420: The 2.6-metre (8.5 ft) and 135-kilogram (298 lb) dwarf sperm whale to the 34-metre (112 ft) and 190-metric-ton (210-short-ton) blue whale. Overall, they tend to dwarf other cetartiodactyls; the blue whale is the largest creature on Earth. Several species have female-biased sexual dimorphism, with the females being larger than the males. One exception is with the sperm whale, which has males larger than
2142-457: The 50° latitude lines. Two fossilized species of Kogia sp. were shown to exhibit sympatry , similar to the two modern members of Kogia , which researchers suggested shows that this behavior has been part of Kogiidae for at least 3 million years. Extant kogiids travel in small groups and rarely surface, potentially to avoid predators like orcas . Kogiidae are deep diving whales, believed to dive up to depths of 500 m. Kogiids feed using
2205-550: 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
2268-447: The baleen whales (Mysticetes) and the toothed whales (Odontocetes). Whales have torpedo-shaped bodies with non-flexible necks, limbs modified into flippers, non-existent external ear flaps, a large tail fin, and flat heads (with the exception of monodontids and ziphiids ). Whale skulls have small eye orbits, long snouts (with the exception of monodontids and ziphiids) and eyes placed on the sides of its head. Whales range in size from
2331-529: The closest living relatives of cetaceans are the hippopotamuses ; these share a semi-aquatic ancestor that branched off from other artiodactyls some 60 mya. Around 40 mya, a common ancestor between the two branched off into cetacea and anthracotheres ; nearly all anthracotheres became extinct at the end of the Pleistocene 2.5 mya, eventually leaving only one surviving lineage – the hippopotamus. Whales split into two separate parvorders around 34 mya –
2394-690: 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
2457-404: The concentration of myoglobin than haemoglobin. Before going on long dives, many whales exhibit a behaviour known as sounding; they stay close to the surface for a series of short, shallow dives while building their oxygen reserves, and then make a sounding dive. The whale ear has specific adaptations to the marine environment. In humans, the middle ear works as an impedance equalizer between
2520-553: The females. Odontocetes, such as the sperm whale, possess teeth with cementum cells overlying dentine cells. Unlike human teeth, which are composed mostly of enamel on the portion of the tooth outside of the gum, whale teeth have cementum outside the gum. Only in larger whales, where the cementum is worn away on the tip of the tooth, does enamel show. Mysticetes have large whalebone , as opposed to teeth, made of keratin. Mysticetes have two blowholes, whereas Odontocetes contain only one. Breathing involves expelling stale air from
2583-524: 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
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2646-567: The intelligence of an animal. 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 mammalian brain size scales at approximately the ⅔ or ¾ exponent of the body mass. Comparison of a particular animal's brain size with the expected brain size based on such allometric analysis provides an encephalisation quotient that can be used as another indication of animal intelligence. Sperm whales have
2709-946: The largely terrestrial mammalian clade Laurasiatheria . Whales do not form a clade or order ; the infraorder Cetacea includes dolphins and porpoises , which are not considered whales in the informal sense. The phylogenetic tree shows the relationships of whales and other mammals, with whale groups marked in green. ( carnivorans and allies) [REDACTED] ( horses , rhinos , tapirs ) [REDACTED] ( camels, llamas ) [REDACTED] ( pigs, hogs, peccaries ) [REDACTED] ( cattle , sheep , antelopes ) [REDACTED] ( hippos ) [REDACTED] ( † Ambulocetus , † Protocetus , † Basilosaurus ) ( right whales , grey whales , rorquals ) ( dolphins , porpoises , beluga whales , narwhals ) ( river dolphins ) ( sperm whales ) ( beaked whales ) Cetaceans are divided into two parvorders. The larger parvorder, Mysticeti (baleen whales),
2772-399: The largest and smallest odontocetes, and spend a large portion of their life hunting squid. P. macrocephalus spends most of its life in search of squid in the depths; these animals do not require any degree of light at all, in fact, blind sperm whales have been caught in perfect health. The behaviour of Kogiids remains largely unknown, but, due to their small lungs, they are thought to hunt in
2835-407: The largest brain mass of any animal on Earth, averaging 8,000 cubic centimetres (490 in ) and 7.8 kilograms (17 lb) in mature males, in comparison to the average human brain which averages 1,450 cubic centimetres (88 in ) in mature males. The brain-to-body mass ratio in some odontocetes, such as belugas and narwhals, is second only to humans. Kogiidae See text Kogiidae
2898-517: The nearsightedness that results from the refraction of light; they contain both rod and cone cells, meaning they can see in both dim and bright light, but they have far more rod cells than they do cone cells. Whales do, however, lack short wavelength sensitive visual pigments in their cone cells indicating a more limited capacity for colour vision than most mammals. Most whales have slightly flattened eyeballs, enlarged pupils (which shrink as they surface to prevent damage), slightly flattened corneas and
2961-440: The neck vertebrae, while increasing stability when swimming at high speeds, decreases flexibility; whales are unable to turn their heads. When swimming, whales rely on their tail fin to propel them through the water. Flipper movement is continuous. Whales swim by moving their tail fin and lower body up and down, propelling themselves through vertical movement, while their flippers are mainly used for steering. Some species log out of
3024-417: The outside air's low impedance and the cochlear fluid's high impedance. In whales, and other marine mammals, there is no great difference between the outer and inner environments. Instead of sound passing through the outer ear to the middle ear, whales receive sound through the throat, from which it passes through a low-impedance fat-filled cavity to the inner ear. The whale ear is acoustically isolated from
3087-440: The pulsed calls of belugas. Pulses in a click train are emitted at intervals of ≈35–50 milliseconds , and in general these inter-click intervals are slightly greater than the round-trip time of sound to the target. Whistles are narrow-band frequency modulated (FM) signals, used for communicative purposes, such as contact calls. Whales are known to teach, learn, cooperate, scheme, and grieve. The neocortex of many species of whale
3150-399: The ratio between observed brain size and expected brain size. The pygmy sperm whale has an EQ of 1.78, while the dwarf sperm whale's EQ is 1.63. Kogiidae do possess spermaceti in their head like sperm whales. However, kogiid spermaceti is unique as the whales are able to control its temperature. Kogiidae are also homodonts , showing teeth all of the same size and shape. Kogiidae possess
3213-464: The right whales. These animals have very large heads, which can make up as much as 40% of their body mass, and much of the head is the mouth. This allows them to take in large amounts of water into their mouths, letting them feed more effectively. Eschrichtiids have one living member: the grey whale. They are bottom feeders, mainly eating crustaceans and benthic invertebrates. They feed by turning on their sides and taking in water mixed with sediment, which
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#17328767434543276-419: The same term [REDACTED] This disambiguation page lists articles associated with the title Black whale . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Black_whale&oldid=1226266364 " Category : Disambiguation pages Hidden categories: Short description
3339-549: The sensation of taste. Whale vocalization is likely to serve several purposes. Some species, such as the humpback whale, communicate using melodic sounds, known as whale song . These sounds may be extremely loud, depending on the species. Humpback whales only have been heard making clicks, while toothed whales use sonar that may generate up to 20,000 watts of sound (+73 dBm or +43 dBw ) and be heard for many miles. Captive whales have occasionally been known to mimic human speech. Scientists have suggested this indicates
3402-515: The shrinking and eventual disappearance of the hind limbs (the first odontocetes and mysticetes 34 mya). Whale morphology shows several examples of convergent evolution , the most obvious being the streamlined fish-like body shape. Other examples include the use of echolocation for hunting in low light conditions — which is the same hearing adaptation used by bats — and, in the rorqual whales, jaw adaptations, similar to those found in pelicans , that enable engulfment feeding. Today,
3465-400: The skull by air-filled sinus pockets, which allow for greater directional hearing underwater. Odontocetes send out high-frequency clicks from an organ known as a melon . This melon consists of fat, and the skull of any such creature containing a melon will have a large depression. The melon size varies between species, the bigger the more dependent they are on it. A beaked whale for example has
3528-429: The sperm whale and bowhead whale, possess discrete rudimentary appendages, which may contain feet and digits. Whales are fast swimmers in comparison to seals, which typically cruise at 5–15 kn, or 9–28 kilometres per hour (5.6–17.4 mph); the fin whale, in comparison, can travel at speeds up to 47 kilometres per hour (29 mph) and the sperm whale can reach speeds of 35 kilometres per hour (22 mph). The fusing of
3591-526: 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
3654-563: 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
3717-461: The water, which may allow them to travel faster. Their skeletal anatomy allows them to be fast swimmers. Most species have a dorsal fin . Whales are adapted for diving to great depths. In addition to their streamlined bodies, they can slow their heart rate to conserve oxygen; blood is rerouted from tissue tolerant of water pressure to the heart and brain among other organs; haemoglobin and myoglobin store oxygen in body tissue; and they have twice
3780-478: The water. Upon striking an object in the water, the sound waves bounce back at the whale. These vibrations are received through fatty tissues in the jaw, which is then rerouted into the ear-bone and into the brain where the vibrations are interpreted. All toothed whales are opportunistic, meaning they will eat anything they can fit in their throat because they are unable to chew. These animals rely on their well-developed flippers and tail fin to propel themselves through
3843-488: The water; they swim by moving their fore-flippers and tail fin up and down. Whale ribs loosely articulate with their thoracic vertebrae at the proximal end, but do not form a rigid rib cage. This adaptation allows the chest to compress during deep dives as the pressure increases. Mysticetes consist of four families: rorquals (balaenopterids) , cetotheriids , right whales (balaenids) , and grey whales (eschrichtiids) . The main difference between each family of mysticete
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#17328767434543906-672: The water; they swim by moving their fore-flippers and tail fin up and down. Whale ribs loosely articulate with their thoracic vertebrae at the proximal end, but they do not form a rigid rib cage. This adaptation allows the chest to compress during deep dives as opposed to resisting the force of water pressure. Excluding dolphins and porpoises, odontocetes consist of four families: belugas and narwhals (monodontids) , sperm whales (physeterids) , dwarf and pygmy sperm whales (kogiids) , and beaked whales (ziphiids) . The differences between families of odontocetes include size, feeding adaptations and distribution. Monodontids consist of two species:
3969-537: The whales' closest terrestrial living relatives. Mysticetes are also known as baleen whales. They have a pair of blowholes side by side and lack teeth; instead they have baleen plates which form a sieve-like structure in the upper jaw made of keratin, which they use to filter plankton from the water. Some whales, such as the humpback, reside in the polar regions where they feed on a reliable source of schooling fish and krill . These animals rely on their well-developed flippers and tail fin to propel themselves through
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