Livyatan melvillei
Encyclopedia


Livyatan melvillei is an extinct
Extinction
In biology and ecology, extinction is the end of an organism or of a group of organisms , normally a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point...

 species of physeteroid whale
Whale
Whale is the common name for various marine mammals of the order Cetacea. The term whale sometimes refers to all cetaceans, but more often it excludes dolphins and porpoises, which belong to suborder Odontoceti . This suborder also includes the sperm whale, killer whale, pilot whale, and beluga...

, which lived during the Miocene
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...

 epoch
Epoch (geology)
An epoch is a subdivision of the geologic timescale based on rock layering. In order, the higher subdivisions are periods, eras and eons. We are currently living in the Holocene epoch...

, approximately 12-13 million years ago.

Discovery

In November 2008, fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...

 remains of Livyatan melvillei were discovered in the sediments of Pisco formation at Cerro Colorado, 35 kilometres (21.7 mi) south-southwest of Ica
Ica (city)
The city of Ica is the capital of the Ica Region in southern Peru. While the area was long inhabited by varying cultures of indigenous peoples, the Spanish conquistador Gerónimo Luis de Cabrera claimed its founding in 1563. As of 2005, it had an estimated population of over 219,856...

, Peru
Peru
Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean....

. The remains include a partially preserved skull with teeth and mandible.
Rotterdam Natural History Museum
Natuurhistorisch Museum Rotterdam
The ' is a natural history museum at Museumpark in Rotterdam, The Netherlands.The museum is located in the Villa Dijkzigt, dating from 1852 and extended in 1995 with a modern glazed pavilion which was designed by the Dutch architect Erick van Egeraat. Villa Dijkzigt was originally built by J. F...

 researcher
Researcher
A researcher is somebody who performs research, the search for knowledge or in general any systematic investigation to establish facts. Researchers can work in academic, industrial, government, or private institutions.-Examples of research institutions:...

 Klaas Post stumbled across them on the final day of a field trip there in November 2008. Post was part of an international team of researchers, led by Dr Christian de Muizon, director of the Natural History Museum
Muséum national d'histoire naturelle
The Muséum national d'Histoire naturelle is the National Museum of Natural History in Paris, France.- History :The museum was formally founded on 10 June 1793, during the French Revolution...

 in Paris, and included other palaeontologists from Utrecht University
Utrecht University
Utrecht University is a university in Utrecht, Netherlands. It is one of the oldest universities in the Netherlands and one of the largest in Europe. Established March 26, 1636, it had an enrollment of 29,082 students in 2008, and employed 8,614 faculty and staff, 570 of which are full professors....

 and the natural history museums of Rotterdam, Museo storia naturale di Pisa
Museo storia naturale di Pisa
Museo storia naturale di Pisa is an Italian natural history museum at Pisa. It is part of the University of Pisa and is now located in Pisa Charterhouse 10 km from the city of Pisa in the comune of Calci....

, the Museum of Natural History of the National University of San Marcos
National University of San Marcos
The National University of San Marcos is the most important and respected higher-education institution in Peru. Its main campus, the University City, is located in Lima...

 in Lima
Lima
Lima is the capital and the largest city of Peru. It is located in the valleys of the Chillón, Rímac and Lurín rivers, in the central part of the country, on a desert coast overlooking the Pacific Ocean. Together with the seaport of Callao, it forms a contiguous urban area known as the Lima...

 and Brussels
Royal Belgian Institute of Natural Sciences
The Royal Belgian Institute of Natural Sciences is a museum in the Belgian capital of Brussels dedicated to natural history. Its most important pieces are 30 fossilized Iguanodon skeletons, which were discovered in 1878 in Bernissart. The dinosaur hall of the museum is the world's largest museum...

.

The fossils have been dated at 12–13 million years old and were prepared in Lima
Lima
Lima is the capital and the largest city of Peru. It is located in the valleys of the Chillón, Rímac and Lurín rivers, in the central part of the country, on a desert coast overlooking the Pacific Ocean. Together with the seaport of Callao, it forms a contiguous urban area known as the Lima...

, Peru
Peru
Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean....

, and are now part of the collection of the Natural History Museum there.

Etymology and nomenclature

Researchers originally assigned the English
English people
The English are a nation and ethnic group native to England, who speak English. The English identity is of early mediaeval origin, when they were known in Old English as the Anglecynn. England is now a country of the United Kingdom, and the majority of English people in England are British Citizens...

 name of the biblical
Hebrew Bible
The Hebrew Bible is a term used by biblical scholars outside of Judaism to refer to the Tanakh , a canonical collection of Jewish texts, and the common textual antecedent of the several canonical editions of the Christian Old Testament...

 monster (Leviathan
Leviathan
Leviathan , is a sea monster referred to in the Bible. In Demonology, Leviathan is one of the seven princes of Hell and its gatekeeper . The word has become synonymous with any large sea monster or creature...

) to this prehistoric whale
Whale
Whale is the common name for various marine mammals of the order Cetacea. The term whale sometimes refers to all cetaceans, but more often it excludes dolphins and porpoises, which belong to suborder Odontoceti . This suborder also includes the sperm whale, killer whale, pilot whale, and beluga...

 as Leviathan melvillei, dedicating the discovery to Herman Melville
Herman Melville
Herman Melville was an American novelist, short story writer, essayist, and poet. He is best known for his novel Moby-Dick and the posthumous novella Billy Budd....

, author of Moby-Dick
Moby-Dick
Moby-Dick; or, The Whale, was written by American author Herman Melville and first published in 1851. It is considered by some to be a Great American Novel and a treasure of world literature. The story tells the adventures of wandering sailor Ishmael, and his voyage on the whaleship Pequod,...

—the researchers behind the excavation of L. melvillei were all fans of this novel. However, the scientific name Leviathan was a junior homonym of Leviathan Koch, 1841 for a genus of mastodon
Mastodon
Mastodons were large tusked mammal species of the extinct genus Mammut which inhabited Asia, Africa, Europe, North America and Central America from the Oligocene through Pleistocene, 33.9 mya to 11,000 years ago. The American mastodon is the most recent and best known species of the group...

 (see Leviathan in Wikispecies). Junior homonyms need to be replaced with new names, except under certain special circumstances (ICZN 1999 Article 60). In August 2010, the authors rectified this situation by coining a new genus name for the whale, Livyatan, from the original Hebrew spelling.

Morphology and habitat

Livyatan melvillei had a body length of 13.5 to 17.5 m (44.3 to 57.4 ), about the same as a modern adult male sperm whale. The skull of Livyatan melvillei is 3 metres (10 ft) long. Unlike the modern sperm whale
Sperm Whale
The sperm whale, Physeter macrocephalus, is a marine mammal species, order Cetacea, a toothed whale having the largest brain of any animal. The name comes from the milky-white waxy substance, spermaceti, found in the animal's head. The sperm whale is the only living member of genus Physeter...

, Physeter macrocephalus, L. melvillei had functional teeth in both its jaws. The jaws of L. melvillei were robust and its temporal fossa
Temporal fossa
The temporal fossa is a shallow depression on the side of the skull bounded by the temporal lines and terminating below the level of the zygomatic arch.-Boundaries:...

 was also considerably larger than in the modern-age sperm whale. L. melvillei is one of the largest raptorial predators yet known, with whale experts using the phrase "the biggest tetrapod bite ever found" to explain their find. The teeth of L. melvillei are up to 36 centimetres (1.2 ft) long and are claimed to be the largest of any animal
Animal
Animals are a major group of multicellular, eukaryotic organisms of the kingdom Animalia or Metazoa. Their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later on in their life. Most animals are motile, meaning they can move spontaneously and...

 yet known.
Larger 'teeth' (tusks) are known - walrus
Walrus
The walrus is a large flippered marine mammal with a discontinuous circumpolar distribution in the Arctic Ocean and sub-Arctic seas of the Northern Hemisphere. The walrus is the only living species in the Odobenidae family and Odobenus genus. It is subdivided into three subspecies: the Atlantic...

 and elephant
Elephant
Elephants are large land mammals in two extant genera of the family Elephantidae: Elephas and Loxodonta, with the third genus Mammuthus extinct...

 tusks, for example - but these are not used directly in eating.

Skull structure

The fossil skull of L. melvillei has a curved basin which suggests it might have had a large spermaceti organ, a series of oil and wax reservoirs separated by connective tissue. This organ is thought to help modern sperm whales to dive deeply to feed. However, L. melvillei is likely to have hunted large prey near the surface, so it appears that this organ would have had other functions. Possible suggestions include echolocation
Echolocation
Echolocation may refer to:* Acoustic location, the general use of sound to locate objects* Animal echolocation, non-human animals emitting sound waves and listening to the echo in order to locate objects or navigate...

, acoustic displays (with the spermaceti organ acting as a resonance chamber) or aggressive headbutting, possibly used against competing males in mating contests or to batter prey.

Diet

Fossil remains of many other animals—including baleen whale
Baleen whale
The Baleen whales, also called whalebone whales or great whales, form the Mysticeti, one of two suborders of the Cetacea . Baleen whales are characterized by having baleen plates for filtering food from water, rather than having teeth. This distinguishes them from the other suborder of cetaceans,...

s, beaked whale
Beaked whale
Beaked whales are 21 species of toothed whales, members of the family Ziphiidae, are notable for their elongated beaks. Beaked whales are one of the world's most extreme divers. They can dive for long periods—20 to 30 minutes is common, and 85 minute dives have been recorded—and to...

s, dolphin
Dolphin
Dolphins are marine mammals that are closely related to whales and porpoises. There are almost forty species of dolphin in 17 genera. They vary in size from and , up to and . They are found worldwide, mostly in the shallower seas of the continental shelves, and are carnivores, mostly eating...

s, porpoise
Porpoise
Porpoises are small cetaceans of the family Phocoenidae; they are related to whales and dolphins. They are distinct from dolphins, although the word "porpoise" has been used to refer to any small dolphin, especially by sailors and fishermen...

s, shark
Shark
Sharks are a type of fish with a full cartilaginous skeleton and a highly streamlined body. The earliest known sharks date from more than 420 million years ago....

s, sea turtle
Sea turtle
Sea turtles are marine reptiles that inhabit all of the world's oceans except the Arctic.-Distribution:...

s, seal
Pinniped
Pinnipeds or fin-footed mammals are a widely distributed and diverse group of semiaquatic marine mammals comprising the families Odobenidae , Otariidae , and Phocidae .-Overview: Pinnipeds are typically sleek-bodied and barrel-shaped...

s and sea birds—have been found at the same site where the remains of L. melvillei have been excavated.

L. melvillei would have been a top predator
Apex predator
Apex predators are predators that have no predators of their own, residing at the top of their food chain. Zoologists define predation as the killing and consumption of another organism...

 of its time along with the giant shark, C. megalodon
Megalodon
The megalodon and ὀδούς ) is an extinct species of shark that lived roughly from 28 to 1.5 million years ago, during the Cenozoic Era .The taxonomic assignment of C...

, which was contemporaneous with L. melvillei in the same region, and the whale probably had a profound impact on the structuring of Miocene marine communities. The appearance of gigantic raptorial sperm whales in the fossil record coincides with a phase of diversification and size-range increase of the baleen-bearing mysticetes in the Miocene.

L. melvillei is likely to have preyed upon 7 – baleen whales, seals and dolphins.

Size estimation

Two physeterids have been chosen by whale experts for comparison to estimate the size of L. melvillei. The anatomy of Physeter macrocephalus yielded a total length (TL) of 13.5 m (= 44.3 feet) for L. melvillei, and that of Zygophyseter
Zygophyseter
Zygophyseter varolai is an extinct cetacean, similar to the sperm whale. The common name of "killer sperm whale" refers both to its relation to modern day sperm whales, and to its similarity in size to and its "probable similar feeding adaptation to the extant delphinid killer whale ".The...

 varolai
yielded a TL of 17.5 m (= 57.5 feet) for L. melvillei.

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