Specimens of Allosaurus
Encyclopedia
Allosaurus was not only one of the most abundant Late Jurassic
dinosaurs, but also one of the best known. Its brain
, anatomy and even behaviour were studied more accurate than those of any dinosaur
on Earth
. Many of its specimens were found: from Utah
, Wyoming
, Colorado
and Montana
to Portugal
. Tendaguru Formation in Tanzania
.
are possibly Antrodemus
, Creosaurus and Labrosaurus. First most of the carnosaur remains, including those of Antrodemus, were assigned to the genus
Megalosaurus
, because it was the only known large theropod in the 1860s. Next, Othniel Charles Marsh
named these animal
s Antrodemus, Creosaurus and Labrosaurus. Howewer they were later determined to be the synonyms of Allosaurus.
But there are several differences between typical Allosaurus fragils and Antrodemus. The skull of A. valens has larger horns and it is shorter than that of A. fragilis.
in 1878. Its possible size is 12 metres (39 ft). This is 1 metre longer than Allosaurus fragilis. Howewer, paleontologists still debate whether it merits distinction at the genus level. Because so few remains were found, it is hard to say with certainty.
693). It is known for many deep injuries on his skeleton. Its ribs, toes and skull were pulverized. But the atrangest wound on its body was its toe. As stated on the BBC series The Ballad of Big Al
, on the hunt the Allosaurus fell and broke its central toe. This wound became infected, and "Big Al" died.
Late Jurassic
The Late Jurassic is the third epoch of the Jurassic Period, and it spans the geologic time from 161.2 ± 4.0 to 145.5 ± 4.0 million years ago , which is preserved in Upper Jurassic strata. In European lithostratigraphy, the name "Malm" indicates rocks of Late Jurassic age...
dinosaurs, but also one of the best known. Its brain
Brain
The brain is the center of the nervous system in all vertebrate and most invertebrate animals—only a few primitive invertebrates such as sponges, jellyfish, sea squirts and starfishes do not have one. It is located in the head, usually close to primary sensory apparatus such as vision, hearing,...
, anatomy and even behaviour were studied more accurate than those of any dinosaur
Dinosaur
Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...
on Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
. Many of its specimens were found: from Utah
Utah
Utah is a state in the Western United States. It was the 45th state to join the Union, on January 4, 1896. Approximately 80% of Utah's 2,763,885 people live along the Wasatch Front, centering on Salt Lake City. This leaves vast expanses of the state nearly uninhabited, making the population the...
, Wyoming
Wyoming
Wyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High...
, Colorado
Colorado
Colorado is a U.S. state that encompasses much of the Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains...
and Montana
Montana
Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...
to Portugal
Portugal
Portugal , officially the Portuguese Republic is a country situated in southwestern Europe on the Iberian Peninsula. Portugal is the westernmost country of Europe, and is bordered by the Atlantic Ocean to the West and South and by Spain to the North and East. The Atlantic archipelagos of the...
. Tendaguru Formation in Tanzania
Tanzania
The United Republic of Tanzania is a country in East Africa bordered by Kenya and Uganda to the north, Rwanda, Burundi, and the Democratic Republic of the Congo to the west, and Zambia, Malawi, and Mozambique to the south. The country's eastern borders lie on the Indian Ocean.Tanzania is a state...
.
Antrodemus, Labrosaurus and Creosaurus
The most famous synonyms of AllosaurusAllosaurus
Allosaurus is a genus of large theropod dinosaur that lived 155 to 150 million years ago during the late Jurassic period . The name Allosaurus means "different lizard". It is derived from the Greek /allos and /sauros...
are possibly Antrodemus
Antrodemus
Antrodemus is a dubious genus of theropod dinosaur from the Kimmeridgian-Tithonian-age Upper Jurassic Morrison Formation of Middle Park, Colorado...
, Creosaurus and Labrosaurus. First most of the carnosaur remains, including those of Antrodemus, were assigned to the genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
Megalosaurus
Megalosaurus
Megalosaurus is a genus of large meat-eating theropod dinosaurs of the Middle Jurassic period of Europe...
, because it was the only known large theropod in the 1860s. Next, Othniel Charles Marsh
Othniel Charles Marsh
Othniel Charles Marsh was an American paleontologist. Marsh was one of the preeminent scientists in the field; the discovery or description of dozens of news species and theories on the origins of birds are among his legacies.Born into a modest family, Marsh was able to afford higher education...
named these 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...
s Antrodemus, Creosaurus and Labrosaurus. Howewer they were later determined to be the synonyms of Allosaurus.
But there are several differences between typical Allosaurus fragils and Antrodemus. The skull of A. valens has larger horns and it is shorter than that of A. fragilis.
Epanterias
The largest member of Allosauridae is possibly Epanterias amplexus. Its fossils were unearthed in Garden Park Fossil Area, ColoradoColorado
Colorado is a U.S. state that encompasses much of the Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains...
in 1878. Its possible size is 12 metres (39 ft). This is 1 metre longer than Allosaurus fragilis. Howewer, paleontologists still debate whether it merits distinction at the genus level. Because so few remains were found, it is hard to say with certainty.
"Big Al"
Another famous Allosaurus specimen, from Howe Quarry, is informally called "Big Al" (MORMOR
Mor or MOR may refer to:In publications:* Mathematics of Operations Research, a quarterly publication on the mathematics of operations research.In mechanics:...
693). It is known for many deep injuries on his skeleton. Its ribs, toes and skull were pulverized. But the atrangest wound on its body was its toe. As stated on the BBC series The Ballad of Big Al
The Ballad of Big Al
The Ballad of Big Al is a combination biography-sequel for Walking with Dinosaurs ...
, on the hunt the Allosaurus fell and broke its central toe. This wound became infected, and "Big Al" died.