Ankalagon
Encyclopedia
Ankalagon saurognathus is an extinct carnivorous mammal
of the family
Mesonychidae
, endemic to North America
during the Paleocene
epoch (63.3—60.2 mya), existing for approximately .
Known from the Paleocene
of New Mexico
, Ankalagon is the largest mesonychid
known from the Paleocene of North America
, and it provides the best evidence for sexual dimorphism
in mesonychids.
species is its size: Ankalagon grew to be as large as a bear, as compared to the coyote or jackal-sized species of Dissacus. In fact, the only North American mesonychids that surpassed Ankalagon in size were the larger species of the Early Eocene genus, Pachyaena
, such as P. gigantea and P. ossifraga, which, too, grew to the size of bears.
Evidence of sexual dimorphism comes from the fact that some jawbones were larger, and had more massive molar teeth better suited to crushing bones than other jawbones, suggesting that the males crushed bones.
, who was mentioned in the Silmarillion by J.R.R. Tolkien
. In the Silmarillion, Ancalagon was described as being one of the more powerful servants of the malevolent being, Morgoth, having been bred to be the fiercest, mightiest, and largest dragon in all of Middle Earth. According to Tolkien, "Ancalagon" translates from Sindarin
as being anc 'jaw', alag 'impetuous'.
Leigh Van Valen studied the New Mexico mesonychid Dissacus saurognathus and eventually came to the conclusion that D. saurognathus differed enough from the sympatric D. navajovius, and from other members of the genus to merit its own genus. Van Valen intended to erect the genus "Ancalagon," but found that it was already occupied by a Middle Cambrian priapulid described by Simon Conway Morris
, Ancalagon minor, a possible free-living ancestor of the parasitic acanthocephalid
s.
The species name, "saurognathus," translates as "lizard jaw."
Mammal
Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
of the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Mesonychidae
Mesonychidae
Mesonychidae is an extinct family of medium to large-sized omnivorous-carnivorous mammals closely related to artiodactyls which were endemic to North America and Eurasia during the Early Paleocene to Late Eocene living from 65—33.9 mya, existing for approximately .- Description :The mesonychids...
, endemic to North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
during the Paleocene
Paleocene
The Paleocene or Palaeocene, the "early recent", is a geologic epoch that lasted from about . It is the first epoch of the Palaeogene Period in the modern Cenozoic Era...
epoch (63.3—60.2 mya), existing for approximately .
Known from the Paleocene
Paleocene
The Paleocene or Palaeocene, the "early recent", is a geologic epoch that lasted from about . It is the first epoch of the Palaeogene Period in the modern Cenozoic Era...
of New Mexico
New Mexico
New Mexico is a state located in the southwest and western regions of the United States. New Mexico is also usually considered one of the Mountain States. With a population density of 16 per square mile, New Mexico is the sixth-most sparsely inhabited U.S...
, Ankalagon is the largest mesonychid
Mesonychid
Mesonychia are an extinct order of medium to large-sized carnivorous mammals that were closely related to artiodactyls and to cetaceans...
known from the Paleocene of North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
, and it provides the best evidence for sexual dimorphism
Sexual dimorphism
Sexual dimorphism is a phenotypic difference between males and females of the same species. Examples of such differences include differences in morphology, ornamentation, and behavior.-Examples:-Ornamentation / coloration:...
in mesonychids.
Description
The main feature that distinguishes A. saurognathus from the ancestral DissacusDissacus
Dissacus is an extinct carnivorous jackal to coyote-sized mammal of the family Mesonychidae, endemic to Asia and North America during the Paleocene through Eocene epochs 65—50.3 mya, existing for approximately ....
species is its size: Ankalagon grew to be as large as a bear, as compared to the coyote or jackal-sized species of Dissacus. In fact, the only North American mesonychids that surpassed Ankalagon in size were the larger species of the Early Eocene genus, Pachyaena
Pachyaena
Pachyaena was a genus of heavily built, relatively short-legged mesonychids that originated from Asia. The species ranged in size from a coyote to a bear...
, such as P. gigantea and P. ossifraga, which, too, grew to the size of bears.
Evidence of sexual dimorphism comes from the fact that some jawbones were larger, and had more massive molar teeth better suited to crushing bones than other jawbones, suggesting that the males crushed bones.
Ecology
The strong jaws, sharp, hooked canines and triangular molars that form a shearing edge typical of other mesonychids suggest that A. saurognathus was a hypercarnivorous apex predator. The massive molars of the males suggest that the males were also scavengers that ate bones.Etymology
The generic name refers to the dragon AncalagonDragon (Middle-earth)
J. R. R. Tolkien's Middle-earth legendarium features dragons closely based on those of European legend.Besides dragon , Tolkien variously used the terms drake and worm .-History:The dragons were created by Morgoth...
, who was mentioned in the Silmarillion by J.R.R. Tolkien
J. R. R. Tolkien
John Ronald Reuel Tolkien, CBE was an English writer, poet, philologist, and university professor, best known as the author of the classic high fantasy works The Hobbit, The Lord of the Rings, and The Silmarillion.Tolkien was Rawlinson and Bosworth Professor of Anglo-Saxon at Pembroke College,...
. In the Silmarillion, Ancalagon was described as being one of the more powerful servants of the malevolent being, Morgoth, having been bred to be the fiercest, mightiest, and largest dragon in all of Middle Earth. According to Tolkien, "Ancalagon" translates from Sindarin
Sindarin
Sindarin is a fictional language devised by J. R. R. Tolkien, and used in his secondary world, often called Middle-earth.Sindarin is one of the many languages spoken by the immortal Elves, called the Eledhrim or Edhellim in Sindarin....
as being anc 'jaw', alag 'impetuous'.
Leigh Van Valen studied the New Mexico mesonychid Dissacus saurognathus and eventually came to the conclusion that D. saurognathus differed enough from the sympatric D. navajovius, and from other members of the genus to merit its own genus. Van Valen intended to erect the genus "Ancalagon," but found that it was already occupied by a Middle Cambrian priapulid described by Simon Conway Morris
Simon Conway Morris
Simon Conway Morris FRS is an English paleontologist made known by his detailed and careful study of the Burgess Shale fossils, an exploit celebrated in Wonderful Life by Stephen Jay Gould...
, Ancalagon minor, a possible free-living ancestor of the parasitic acanthocephalid
Acanthocephala
Acanthocephala is a phylum of parasitic worms known as acanthocephales, thorny-headed worms, or spiny-headed worms, characterized by the presence of an evertable proboscis, armed with spines, which it uses to pierce and hold the gut wall of its host...
s.
The species name, "saurognathus," translates as "lizard jaw."