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70-547: Sperm whales are a common sight on the surface of the Suvadiva Channel. Maldives One and Half Degree Huvadhoo Channel tides for fishing. https://tideking.com/Maldives/Other/One-and-Half-Degree-Channel/Fishing/ This channel lies between Haddhunmathi Atoll and Huvadhu Atoll and it is the broadest channel between any other atoll of Maldives. In the British Admiralty charts it is called One and

140-624: A fixative in perfumes , among other uses. Beachcombers look out for ambergris as flotsam . Sperm whaling was a major industry in the 19th century, depicted in the novel Moby-Dick . The species is protected by the International Whaling Commission moratorium, and is listed as vulnerable by the International Union for Conservation of Nature . The name "sperm whale" is a clipping of "spermaceti whale". Spermaceti , originally mistakenly identified as

210-425: A Half Degree Channel . On old French maps it appeared as Courant de Souadou . Roughly in the middle of the broad Huvadu channel there is a small bank known as Medutila (also called Derahaa ). This place is the peak of a submarine mountain, and perhaps an atoll in the process of formation. This submerged bank is very difficult to spot for at its shallowest point there is a depth of 6 fathoms (12 m). It looks like

280-452: A deep sleep for about 7 percent of the time, most often between 6 p.m. and midnight. Sperm whales have 21 pairs of chromosomes ( 2n=42 ). The genome of live whales can be examined by recovering shed skin. After Valentine Worthington and William E. Schevill confirmed the existence of sperm whale vocalization, further studies found that sperm whales are capable of emitting sounds at a source level of 230 decibels   –   making

350-424: A down force of about 392 newtons (88 lb f ) and allows the whale to dive with less effort. During the hunt, oxygen consumption, together with blood vessel dilation, produces heat and melts the spermaceti, increasing its buoyancy and enabling easy surfacing. However, more recent work has found many problems with this theory including the lack of anatomical structures for the actual heat exchange. Another issue

420-491: A harvested sperm whale accurately described the age and future life expectancy of a given individual. The level of wax esters in the spermaceti organ increases with the age of the whale: 38–51% in calves, 58–87% in adult females, and 71–94% in adult males. Spermaceti wax is extracted from sperm oil by crystallisation at 6 °C (43 °F), when treated by pressure and a chemical solution of caustic alkali . Spermaceti forms brilliant white crystals that are hard but oily to

490-415: A human's. Sperm whales can live 70 years or more. Sperm whales' heads are filled with a waxy substance called " spermaceti " (sperm oil), from which the whale derives its name. Spermaceti was a prime target of the whaling industry and was sought after for use in oil lamps, lubricants, and candles. Ambergris , a solid waxy waste product sometimes present in its digestive system, is still highly valued as

560-506: A liquid mixture of fats and waxes called spermaceti . The purpose of this complex is to generate powerful and focused clicking sounds, the existence of which was proven by Valentine Worthington and William Schevill when a recording was produced on a research vessel in May 1959. The sperm whale uses these sounds for echolocation and communication. The spermaceti organ is like a large barrel of spermaceti. Its surrounding wall, known as

630-416: A means of adjusting the whale's buoyancy , since the density of the spermaceti changes with its phase. Another hypothesis has been that it is used as a cushion to protect the sperm whale's delicate snout while diving. The most likely primary function of the spermaceti organ is to add internal echo or resonator clicks to the sonar echolocation clicks emitted by the respiratory organs. This makes possible

700-425: A number of specific adaptations for the aquatic environment. The diameter of the aortic arch increases as it leaves the heart. This bulbous expansion acts as a windkessel , ensuring a steady blood flow as the heart rate slows during diving. The arteries that leave the aortic arch are positioned symmetrically. There is no costocervical artery . There is no direct connection between the internal carotid artery and

770-416: A paler blue patch surrounded by huge expanses of the deepest ocean. There, no island can be seen in the horizon for many dozens of miles. 1°30′00″N 73°00′00″E  /  1.50000°N 73.00000°E  / 1.50000; 73.00000 Sperm whales The sperm whale or cachalot ( Physeter macrocephalus ) is the largest of the toothed whales and the largest toothed predator . It

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840-409: A single, pure spermaceti candle. Spermaceti is derived from Medieval Latin sperma ceti , meaning "whale sperm " (from Latin sperma meaning " semen " or "seed", and ceti , the genitive form of "whale"). The substance was initially believed to be whale semen , due to its appearance when fresh. The substance is also the origin of the name of the sperm whale . Raw spermaceti is liquid within

910-461: A sperm whale, the whalers would pull the carcass alongside the ship, cut off the head and pull it on deck. Then, they would cut a hole in it and bail out the matter inside with a bucket. The harvested matter, raw spermaceti, was stored in casks to be processed back on land. A large whale could yield as much as 500 US gallons (1,900 L; 420 imp gal). The spermaceti was boiled and strained of impurities to prevent it from going rancid. On land,

980-524: Is 2,684 m/s (at 40 kHz, 36 °C), making it nearly twice as good a conductor of sounds as the oil in a dolphin's melon . Spermaceti is insoluble in water, very slightly soluble in cold ethanol , but easily dissolved in ether , chloroform , carbon disulfide , and boiling ethanol. Spermaceti consists principally of cetyl palmitate (the ester of cetyl alcohol and palmitic acid ), C 15 H 31 COOC 16 H 33 . Simple triglycerides are seen as well. A botanical alternative to spermaceti

1050-490: Is a derivative of jojoba oil , jojoba esters , C 19 H 41 COOC 20 H 41 , a solid wax, which is chemically and physically very similar to spermaceti and may be used in many of the same applications. Currently, disagreement exists on what biological purpose or purposes spermaceti serves. The proportion of wax esters retained by an average (living) whale head appears to reflect buoyancy influenced by heat. Changes in density likely enhance echolocation. It might be used as

1120-566: Is cited by some authors as the largest accurately measured. It has been estimated to weigh 80 tonnes (79 long tons; 88 short tons). In a review of size variation in marine megafauna, McClain and colleagues noted that the International Whaling Commission's data contained eight individuals larger than 20.7 metres (68 ft). The authors supported a 24-metre (79 ft) male from the South Pacific in 1933 as

1190-401: Is estimated to have weighed 57 tonnes (56 long tons; 63 short tons). By contrast, the second largest toothed whale ( Baird's beaked whale ) measures up to 12.8 meters (42 ft) and weighs up to 14 tonnes (15 short tons). There are occasional reports of individual sperm whales achieving even greater lengths, with some historical claims reaching or exceeding 80 feet (24 m). One example

1260-421: Is not the only factor. Elephants and dolphins also have larger brains than humans. The sperm whale has a lower encephalization quotient than many other whale and dolphin species, lower than that of non-human anthropoid apes , and much lower than that of humans. The sperm whale's cerebrum is the largest in all mammalia, both in absolute and relative terms. The olfactory system is reduced, suggesting that

1330-476: Is that if the spermaceti does indeed cool and solidify, it would affect the whale's echolocation ability just when it needs it to hunt in the depths. Herman Melville 's fictional story Moby-Dick suggests that the "case" containing the spermaceti serves as a battering ram for use in fights between males. A few famous instances include the well-documented sinking of the ships Essex and Ann Alexander by attackers estimated to weigh only one-fifth as much as

1400-425: Is that the teeth are used in aggression between males. Mature males often show scars which seem to be caused by the teeth . Rudimentary teeth are also present in the upper jaw, but these rarely emerge into the mouth. Analyzing the teeth is the preferred method for determining a whale's age. Like the age-rings in a tree, the teeth build distinct layers of cementum and dentine as they grow. The sperm whale brain

1470-399: Is the largest known of any modern or extinct animal, weighing on average about 7.8 kilograms (17 lb) (with the smallest known weighing 6.4 kilograms (14 lb) and the largest known weighing 9.2 kilograms (20 lb)), more than five times heavier than a human brain , and has a volume of about 8,000 cm . Although larger brains generally correlate with higher intelligence, it

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1540-427: Is the only living member of the genus Physeter and one of three extant species in the sperm whale family , along with the pygmy sperm whale and dwarf sperm whale of the genus Kogia . The sperm whale is a pelagic mammal with a worldwide range, and will migrate seasonally for feeding and breeding. Females and young males live together in groups, while mature males (bulls) live solitary lives outside of

1610-539: Is the whale that sank the Essex (one of the incidents behind Moby-Dick ), which was claimed to be 85 feet (26 m). However, there is disagreement as to the accuracy of some of these claims, which are often considered exaggerations or as being measured along the curves of the body. An individual measuring 20.7 metres (68 ft) was reported from a Soviet whaling fleet near the Kuril Islands in 1950 and

1680-563: Is unlikely to be confused with any other species. The sperm whale's distinctive shape comes from its very large, block-shaped head, which can be one-quarter to one-third of the animal's length. The S-shaped blowhole is located very close to the front of the head and shifted to the whale's left. This gives rise to a distinctive bushy, forward-angled spray. The sperm whale's flukes (tail lobes) are triangular and very thick. Proportionally, they are larger than that of any other cetacean, and are very flexible. The whale lifts its flukes high out of

1750-631: Is very thick and contains a fibrous tapetum lucidum . Like other toothed whales, the sperm whale can retract and protrude its eyes, thanks to a 2-cm-thick retractor muscle attached around the eye at the equator, but are unable to roll the eyes in their sockets. According to Fristrup and Harbison (2002), sperm whale's eyes afford good vision and sensitivity to light. They conjectured that sperm whales use vision to hunt squid, either by detecting silhouettes from below or by detecting bioluminescence. If sperm whales detect silhouettes, Fristrup and Harbison suggested that they hunt upside down, allowing them to use

1820-687: The Greek physētēr ( φυσητήρ ), meaning 'blowpipe, blowhole (of a whale)', or – as a pars pro toto – 'whale'. The specific name macrocephalus is Latinized from the Greek makroképhalos ( μακροκέφαλος 'big-headed'), from makros ( μακρός ) + kephalē ( κεφαλή ). Its synonymous specific name catodon means 'down-tooth', from the Greek elements cat(a)- ('below') and odṓn ('tooth'); so named because it has visible teeth only in its lower jaw. ( See " Jaws and teeth " below. ) Another synonym australasianus (' Australasian ')

1890-477: The case , is extremely tough and fibrous. The case can hold within it up to 1,900 litres of spermaceti. It is proportionately larger in males. This oil is a mixture of triglycerides and wax esters . It has been suggested that it is homologous to the dorsal bursa organ found in dolphins. The proportion of wax esters in the spermaceti organ increases with the age of the whale: 38–51% in calves, 58–87% in adult females, and 71–94% in adult males. The spermaceti at

1960-420: The 17th century for human use in cosmetics, textiles, and candles. Theories for the spermaceti organ's biological function suggest that it may control buoyancy , act as a focusing apparatus for the whale's sense of echolocation , or possibly both. Concrete evidence supports both theories. The buoyancy theory holds that the sperm whale is capable of heating the spermaceti, lowering its density and thus allowing

2030-401: The animal's length. Plunging to 2,250 metres (7,380 ft), it is the third deepest diving mammal, exceeded only by the southern elephant seal and Cuvier's beaked whale . The sperm whale uses echolocation and vocalization with source level as loud as 236 decibels (re 1 μPa m) underwater, the loudest of any animal. It has the largest brain on Earth, more than five times heavier than

2100-417: The brain and other essential organs when oxygen levels deplete. The spermaceti organ may also play a role by adjusting buoyancy (see below ). The arterial retia mirabilia are extraordinarily well-developed. The complex arterial retia mirabilia of the sperm whale are more extensive and larger than those of any other cetacean. Atop the whale's skull is positioned a large complex of organs filled with

2170-399: The casks were allowed to chill during the winter, causing the spermaceti to congeal into a spongy and viscous mass. The congealed matter was then loaded into wool sacks and placed in a press to squeeze out the liquid. This liquid was bottled and sold as "winter-strained sperm oil". This was the most valuable product - an oil that remained liquid in freezing winter temperatures. Later, during

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2240-581: The contents of the head of a sperm whale. The crews seeking spermaceti routinely left on three-year tours on several oceans. Cetaceous lamp oil was a commodity that created many maritime fortunes. Candlepower , a photometric unit defined in the United Kingdom Act of Parliament Metropolitan Gas Act 1860 and adopted at the International Electrotechnical Conference of 1883, was based on the light produced by

2310-415: The core of the organ has a higher wax content than the outer areas. The speed of sound in spermaceti is 2,684 m/s (at 40 kHz, 36 °C), making it nearly twice as fast as in the oil in a dolphin's melon . Below the spermaceti organ lies the "junk" which consists of compartments of spermaceti separated by cartilage. It is analogous to the melon found in other toothed whales. The structure of

2380-489: The echoes. A continuous fat-filled canal transmits received sounds to the inner ear. Spermaceti Spermaceti / s p ɜː m ə ˈ s iː t i / is a waxy substance found in the head cavities of the sperm whale (and, in smaller quantities, in the oils of other whales). Spermaceti is created in the spermaceti organ inside the whale's head. This organ may contain as much as 1,900 litres (500 US gal) of spermaceti. It has been extracted by whalers since

2450-507: The family Physeteridae . Two species of the related extant genus Kogia , the pygmy sperm whale Kogia breviceps and the dwarf sperm whale K. sima , are placed either in this family or in the family Kogiidae . In some taxonomic schemes the families Kogiidae and Physeteridae are combined as the superfamily Physeteroidea (see the separate entry on the sperm whale family ). Swedish ichthyologist Peter Artedi described it as Physeter catodon in his 1738 work Genera piscium , from

2520-484: The forward parts of the ventral visual fields for binocular vision . For some time researchers have been aware that pods of sperm whales may sleep for short periods, assuming a vertical position with their heads just below or at the surface, or head down. A 2008 study published in Current Biology recorded evidence that whales may sleep with both sides of the brain. It appears that some whales may fall into

2590-659: The genus Physeter published by Linnaeus concurrently with P. catodon . This proposition was based on the grounds that the names were synonyms published simultaneously, and, therefore, the ICZN Principle of the First Reviser should apply. In this instance, it led to the choice of P. macrocephalus over P. catodon , a view re-stated in Holthuis, 1987. This has been adopted by most subsequent authors, although Schevill (1986 and 1987 ) argued that macrocephalus

2660-453: The head of the sperm whale, and is said to have a smell similar to raw milk. It is composed mostly of wax esters (chiefly cetyl palmitate ) and a smaller proportion of triglycerides . Unlike other toothed whales, most of the carbon chains in the wax esters are relatively long ( C 10 −C 22 ). The blubber oil of the whale is about 66% wax. When it cools to 30 °C or below, the waxes begin to solidify. The speed of sound in spermaceti

2730-405: The junk redistributes physical stress across the skull and may have evolved to protect the head during ramming. Running through the head are two air passages. The left passage runs alongside the spermaceti organ and goes directly to the blowhole, whilst the right passage runs underneath the spermaceti organ and passes air through a pair of phonic lips and into the distal sac at the very front of

2800-477: The knobs trap a film of air that is consistent whatever the orientation or depth of the whale, making it an excellent sound mirror . The spermaceti organs may also help adjust the whale's buoyancy . It is hypothesized that before the whale dives, cold water enters the organ, and it is likely that the blood vessels constrict, reducing blood flow, and, hence, temperature. The wax therefore solidifies and reduces in volume. The increase in specific density generates

2870-1241: The largest international association of marine mammal scientists in the world, officially uses Physeter macrocephalus when publishing their definitive list of marine mammal species . The sperm whale is the largest toothed whale and is among the most sexually dimorphic of all cetaceans . Both sexes are about the same size at birth, but mature males are typically 30% to 50% longer and three times as massive as females. Newborn sperm whales are usually between 3.7 and 4.3 meters (12 and 14 ft) long. Female sperm whales are sexually mature at 8 to 9 meters (26 to 30 ft) in length, whilst males are sexually mature at 11 to 12 meters (36 to 39 ft). Female sperm whales are physically mature at about 10.6 to 11 meters (35 to 36 ft) in length and generally do not achieve lengths greater than 12 metres (39 ft). The largest female sperm whale measured up to 12.3 meters (40 ft) long, and an individual of such size would have weighed about 17 tonnes (19 short tons). Male sperm whales are physically mature at about 15 to 16 meters (49 to 52 ft) in length, and larger males can generally achieve 18 to 19 meters (59 to 62 ft). An 18 meters (59 ft) long male sperm whale

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2940-662: The largest recorded. However, sizes like these are rare, with 95% of recorded sperm whales below 15.85 metres (52.0 ft). In 1853, one sperm whale was reported at 62 feet (19 m) in length, with a head measuring 20 feet (6.1 m). Large lower jawbones are held in the British Natural History Museum and the Oxford University Museum of Natural History , measuring 5 metres (16 ft) and 4.7 metres (15 ft), respectively. The average size of sperm whales has decreased over

3010-455: The left side of the skull. The sperm whale's lower jaw is very narrow and underslung. The sperm whale has 18 to 26 teeth on each side of its lower jaw which fit into sockets in the upper jaw. The teeth are cone-shaped and weigh up to 1 kilogram (2.2 lb) each. The teeth are functional, but do not appear to be necessary for capturing or eating squid, as well-fed animals have been found without teeth or even with deformed jaws. One hypothesis

3080-443: The longest intestinal system in the world, exceeding 300 m in larger specimens. The sperm whale has a four-chambered stomach that is similar to ruminants . The first secretes no gastric juices and has very thick muscular walls to crush the food (since whales cannot chew) and resist the claw and sucker attacks of swallowed squid. The second chamber is larger and is where digestion takes place. Undigested squid beaks accumulate in

3150-425: The mating season. The females cooperate to protect and nurse their young. Females give birth every four to twenty years, and care for the calves for more than a decade. A mature, healthy sperm whale has no natural predators, although calves and weakened adults are sometimes killed by pods of killer whales (orcas). Mature males average 16 metres (52 ft) in length, with the head representing up to one-third of

3220-430: The melon. At the posterior end of this spermaceti complex is the frontal sac, which covers the concave surface of the cranium. The posterior wall of the frontal sac is covered with fluid-filled knobs, which are about 4–13 mm in diameter and separated by narrow grooves. The anterior wall is smooth. The knobbly surface reflects sound waves that come through the spermaceti organ from the phonic lips. The grooves between

3290-405: The names used by Linnaeus. Both names are still used, although most recent authors now accept macrocephalus as the valid name, limiting catodon 's status to a lesser synonym. Until 1974, the species was generally known as P. catodon . In that year, however, Dutch zoologists Antonius M. Husson and Lipke Holthuis proposed that the correct name should be P. macrocephalus , the second name in

3360-407: The nose. The distal sac is connected to the blowhole and the terminus of the left passage. When the whale is submerged, it can close the blowhole, and air that passes through the phonic lips can circulate back to the lungs. The sperm whale, unlike other odontocetes, has only one pair of phonic lips, whereas all other toothed whales have two, and it is located at the front of the nose instead of behind

3430-550: The origin is uncertain, but it suggests that it comes from the Vulgar Latin cappula 'sword hilts'. The word cachalot came to English via French from Spanish or Portuguese cachalote , perhaps from Galician /Portuguese cachola 'big head'. The term is retained in the Russian word for the animal, kashalot ( кашалот ), as well as in many other languages. The scientific genus name Physeter comes from

3500-611: The report of a beached specimen in Orkney in 1693 and two beached in the Netherlands in 1598 and 1601. The 1598 specimen was near Berkhey. The sperm whale is one of the species originally described by Carl Linnaeus in his landmark 1758 10th edition of Systema Naturae . He recognised four species in the genus Physeter . Experts soon realised that just one such species exists, although there has been debate about whether this should be named P. catodon or P. macrocephalus , two of

3570-413: The second chamber – as many as 18,000 have been found in some dissected specimens. Most squid beaks are vomited by the whale, but some occasionally make it to the hindgut. Such beaks precipitate the formation of ambergris . In 1959, the heart of a 22 metric-ton (24 short-ton) male taken by whalers was measured to be 116 kilograms (256 lb), about 0.5% of its total mass. The circulatory system has

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3640-477: The ships. The sperm whale's eye does not differ greatly from those of other toothed whales except in size. It is the largest among the toothed whales, weighing about 170 g. It is overall ellipsoid in shape, compressed along the visual axis, measuring about 7×7×3 cm. The cornea is elliptical and the lens is spherical. The sclera is very hard and thick, roughly 1 cm anteriorly and 3 cm posteriorly. There are no ciliary muscles . The choroid

3710-494: The sound energy is then reflected off the frontal sac at the cranium and into the melon, whose lens-like structure focuses it. Some of the sound will reflect back into the spermaceti organ and back towards the front of the whale's nose, where it will be reflected through the spermaceti organ a third time. This back and forth reflection which happens on the scale of a few milliseconds creates a multi-pulse click structure. This multi-pulse click structure allows researchers to measure

3780-423: The sperm whale has a poor sense of taste and smell. By contrast, the auditory system is enlarged. The pyramidal tract is poorly developed, reflecting the reduction of its limbs. The sperm whale respiratory system has adapted to cope with drastic pressure changes when diving. The flexible ribcage allows lung collapse, reducing nitrogen intake, and metabolism can decrease to conserve oxygen . Between dives,

3850-417: The sperm whale has a vestigial pelvis that is not connected to the spine. Like that of other toothed whales , the skull of the sperm whale is asymmetrical so as to aid echolocation . Sound waves that strike the whale from different directions will not be channeled in the same way. Within the basin of the cranium, the openings of the bony narial tubes (from which the nasal passages spring) are skewed towards

3920-411: The sperm whale surfaces to breathe for about eight minutes before diving again. Odontoceti (toothed whales) breathe air at the surface through a single, S-shaped blowhole, which is extremely skewed to the left. Sperm whales spout (breathe) 3–5 times per minute at rest, increasing to 6–7 times per minute after a dive. The blow is a noisy, single stream that rises up to 2 metres (6.6 ft) or more above

3990-422: The sperm whale the loudest animal in the world. When echolocating , the sperm whale emits a directionally focused beam of broadband clicks. Clicks are generated by forcing air through a pair of phonic lips (also known as "monkey lips" or " museau de singe ") at the front end of the nose, just below the blowhole. The sound then travels backwards along the length of the nose through the spermaceti organ. Most of

4060-546: The spine by flexible cartilage, which allows the ribcage to collapse rather than snap under high pressure. While sperm whales are well adapted to diving, repeated dives to great depths have long-term effects. Bones show the same avascular necrosis that signals decompression sickness in humans. Older skeletons showed the most extensive damage, whereas calves showed no damage. This damage may indicate that sperm whales are susceptible to decompression sickness, and sudden surfacing could be lethal to them. Like that of all cetaceans,

4130-410: The spine of the sperm whale has reduced zygapophysial joints , of which the remnants are modified and are positioned higher on the vertebral dorsal spinous process, hugging it laterally, to prevent extensive lateral bending and facilitate more dorso-ventral bending. These evolutionary modifications make the spine more flexible but weaker than the spines of terrestrial vertebrates. Like many cetaceans,

4200-411: The surface and points forward and left at a 45° angle. On average, females and juveniles blow every 12.5 seconds before dives, while large males blow every 17.5 seconds before dives. A sperm whale killed 160 km (100 mi) south of Durban, South Africa, after a 1-hour, 50-minute dive was found with two dogfish ( Scymnodon sp.), usually found at the sea floor , in its belly. The sperm whale has

4270-415: The touch, and are devoid of taste or smell, making it very useful as an ingredient in cosmetics, leatherworking, and lubricants. The substance was also used in making candles of a standard photometric value, in the dressing of fabrics, and as a pharmaceutical excipient , especially in cerates and ointments . The whaling industry in the 17th and 18th centuries was developed to find, harvest, and refine

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4340-505: The vessels of the brain. Their circulatory system has adapted to dive at great depths, as much as 2,250 metres (7,382 ft) for up to 120 minutes. More typical dives are around 400 metres (1,310 ft) and 35 minutes in duration. Myoglobin , which stores oxygen in muscle tissue, is much more abundant than in terrestrial animals. The blood has a high density of red blood cells , which contain oxygen-carrying haemoglobin . The oxygenated blood can be directed towards only

4410-450: The water as it begins a feeding dive. It has a series of ridges on the back's caudal third instead of a dorsal fin . The largest ridge was called the 'hump' by whalers, and can be mistaken for a dorsal fin because of its shape and size. In contrast to the smooth skin of most large whales, its back skin is usually wrinkly and has been likened to a prune by whale-watching enthusiasts. Albinos have been reported. The ribs are bound to

4480-404: The whale sensing the motion of its prey and its position. The changing distance to the prey affects the time interval between the returning clicks reflected by the prey. This would explain the low density and high compressibility of the spermaceti, which enhance the resonance by the contrast of the acoustic properties of the sea water and of the hard tissue surrounding the spermaceti. After killing

4550-437: The whale to float; for the whale to sink again, it must take water into its blowhole, which cools the spermaceti into a denser solid. This claim has been called into question by recent research that indicates a lack of biological structures to support this heat exchange, and the fact that the change in density is too small to be meaningful until the organ grows to a huge size. Measurement of the proportion of wax esters retained by

4620-418: The whale's spermaceti organ using only the sound of its clicks. Because the interval between pulses of a sperm whale's click is related to the length of the sound producing organ, an individual whale's click is unique to that individual. However, if the whale matures and the size of the spermaceti organ increases, the tone of the whale's click will also change. The lower jaw is the primary reception path for

4690-490: The whales' semen , is the semi-liquid, waxy substance found within the whale's head. ( See " Spermaceti organ and melon " below. ) The sperm whale is also known as the "cachalot", which is thought to derive from the archaic French for 'tooth' or 'big teeth', as preserved for example in the word caishau in the Gascon dialect (a word of either Romance or Basque origin). The etymological dictionary of Corominas says

4760-407: The years, probably due to pressure from whaling. Another view holds that exploitation by overwhaling had virtually no effect on the size of the bull sperm whales, and their size may have actually increased in current times on the basis of density dependent effects. Old males taken at Solander Islands were recorded to be extremely large and unusually rich in blubbers. The sperm whale's unique body

4830-497: Was applied to sperm whales in the Southern Hemisphere. The sperm whale belongs to the order Cetartiodactyla , the order containing all cetaceans and even-toed ungulates . It is a member of the unranked clade Cetacea , with all the whales, dolphins, and porpoises, and further classified into Odontoceti , containing all the toothed whales and dolphins. It is the sole extant species of its genus, Physeter , in

4900-470: Was published with an inaccurate description and that therefore only the species catodon was valid, rendering the principle of "First Reviser" inapplicable. The most recent version of ITIS has altered its usage from P. catodon to P. macrocephalus , following L. B. Holthuis and more recent (2008) discussions with relevant experts. Furthermore, The Taxonomy Committee of the Society for Marine Mammalogy ,

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