Scott Hanko
Anatotitan copei Dinosaur
Anatotitan (pronounced /əˌnætɵˈtaɪtən/ ə-NAT-o-TY-tən, "large duck") is a genus of flat-headed or hadrosaurine hadrosaurid ornithopod dinosaur (a "duck-billed dinosaur") from the very end of the Cretaceous Period, in what is now North America. Remains of Anatotitan have been preserved in the Hell Creek and Lance Formations, which are dated to the late Maastrichtian stage of the Late Cretaceous Period, representing the last three million years before the extinction of the dinosaurs (68 to 65 million years ago). This dinosaur is known from at least six specimens pertaining to two species, discovered in the U.S. states of South Dakota and Montana. Several of these specimens are extremely complete skeletons with well-preserved skulls. It was a large animal, up to approximately 12 meters (39 ft) in length, with an extremely long and low skull. Anatotitan exhibits one of the most striking examples of the "duckbill" snout common to hadrosaurs. It has a long taxonomic history, including decades classified with the genera Anatosaurus, Diclonius, and Trachodon.
Like many dinosaurs, Anatotitan has a long and somewhat confusing taxonomic history. The holotype, or specimen on which the genus is based, was a complete skull and most of a skeleton collected in 1882 by Dr. J. L. Wortman and R. S. Hill[4] for famous American paleontologist Edward Drinker Cope. This specimen, found in Hell Creek Formation rocks, came from northeast of the Black Hills of South Dakota and originally had extensive skin impressions. It was missing most of the pelvis and part of the torso due to a stream cutting through it. The bill had impressions of a horny sheath with a tooth-like series of interlocking points on the upper and lower jaws. When describing this specimen (now the holotype of Anatotitan copei, AMNH 5730), Cope assigned it to Diclonius mirabilis. This combination was created by combining Diclonius, a hadrosaurid genus based on teeth and described by Cope, with Trachodon mirabilis, an older name based on teeth and published by Joseph Leidy. Cope, believing that Leidy had abandoned Trachodon, assigned the old species to his genus. Leidy had come to recognize that his Trachodon was based on the remains of multiple kinds of dinosaurs, and had made some attempts to revise the genus, but did not make a formal declaration of his intentions.
Cope's description promoted hadrosaurids as amphibious, contributing to this long-time image. His reasoning was that the teeth of the lower jaw were weakly connected to the bone and liable to break off if used to consume terrestrial food, and he described the beak as weak as well. Unfortunately for Cope, aside from misidentifying several of the bones of the skull, by chance the lower jaws he was studying were missing the walls supporting the teeth from the inside; the teeth were actually well-supported. This specimen, AMNH 5730, was purchased by the American Museum of Natural History in 1899. Cope intended to describe the skeleton as well as the skull, but his promised paper never appeared.
Several years after Cope's description, his rival Othniel Charles Marsh published on a sizable lower jaw recovered by John Bell Hatcher in 1889 from Lance Formation rocks in Niobrara County, Wyoming. Marsh named this partial jaw Trachodon longiceps. It is cataloged as YPM 616. As noted by Lull and Wright, this long slender partial jaw shares with Cope's specimen a prominent ridge running on its side. However, it is much larger: Cope's specimen had a dentary, or tooth-bearing bone of the lower jaw, 92.0 centimeters (36.2 in) long, whereas Marsh's dentary was estimated at 110.0 centimeters (43.3 in) long.
A second mostly complete skeleton (AMNH 5886) was found in 1904 in Hell Creek Formation rocks at Crooked Creek in central Montana by Oscar Hunter, a rancher. Upon finding the partially-exposed specimen, he and a companion argued about whether or not the remains were recent or fossil. Hunter demonstrated that they were brittle and thus stone by kicking the tops off the vertebrae, an act later lamented by the eventual collector Barnum Brown. Another cowboy, Alfred Sensiba, bought the specimen from Hunter for a pistol, and later sold it to Brown, who excavated it for the American Museum of Natural History in 1906. This specimen had a nearly complete vertebral column, permitting the restoration of Cope's specimen. In 1907, these two specimens were famously mounted side-by-side in the American Museum of Natural History, under the name Trachodon mirabilis. Cope's specimen is positioned on fours with its head down, as if feeding, because it has the better skull, while Brown's specimen, with a less perfect skull, is posed bipedally with the head less accessible. Henry Fairfield Osborn described the tableau as representing the two animals feeding along a marsh, the standing individual having been startled by the approach of a Tyrannosaurus. Impressions of appropriate plant remains and shells based on associated fossils were included on the base of the group, including ginkgo leaves, Sequoia cones, and horsetail rushes.
American Museum of Natural History, New York City, NY.
Anatotitan copei Dinosaur
Anatotitan (pronounced /əˌnætɵˈtaɪtən/ ə-NAT-o-TY-tən, "large duck") is a genus of flat-headed or hadrosaurine hadrosaurid ornithopod dinosaur (a "duck-billed dinosaur") from the very end of the Cretaceous Period, in what is now North America. Remains of Anatotitan have been preserved in the Hell Creek and Lance Formations, which are dated to the late Maastrichtian stage of the Late Cretaceous Period, representing the last three million years before the extinction of the dinosaurs (68 to 65 million years ago). This dinosaur is known from at least six specimens pertaining to two species, discovered in the U.S. states of South Dakota and Montana. Several of these specimens are extremely complete skeletons with well-preserved skulls. It was a large animal, up to approximately 12 meters (39 ft) in length, with an extremely long and low skull. Anatotitan exhibits one of the most striking examples of the "duckbill" snout common to hadrosaurs. It has a long taxonomic history, including decades classified with the genera Anatosaurus, Diclonius, and Trachodon.
Like many dinosaurs, Anatotitan has a long and somewhat confusing taxonomic history. The holotype, or specimen on which the genus is based, was a complete skull and most of a skeleton collected in 1882 by Dr. J. L. Wortman and R. S. Hill[4] for famous American paleontologist Edward Drinker Cope. This specimen, found in Hell Creek Formation rocks, came from northeast of the Black Hills of South Dakota and originally had extensive skin impressions. It was missing most of the pelvis and part of the torso due to a stream cutting through it. The bill had impressions of a horny sheath with a tooth-like series of interlocking points on the upper and lower jaws. When describing this specimen (now the holotype of Anatotitan copei, AMNH 5730), Cope assigned it to Diclonius mirabilis. This combination was created by combining Diclonius, a hadrosaurid genus based on teeth and described by Cope, with Trachodon mirabilis, an older name based on teeth and published by Joseph Leidy. Cope, believing that Leidy had abandoned Trachodon, assigned the old species to his genus. Leidy had come to recognize that his Trachodon was based on the remains of multiple kinds of dinosaurs, and had made some attempts to revise the genus, but did not make a formal declaration of his intentions.
Cope's description promoted hadrosaurids as amphibious, contributing to this long-time image. His reasoning was that the teeth of the lower jaw were weakly connected to the bone and liable to break off if used to consume terrestrial food, and he described the beak as weak as well. Unfortunately for Cope, aside from misidentifying several of the bones of the skull, by chance the lower jaws he was studying were missing the walls supporting the teeth from the inside; the teeth were actually well-supported. This specimen, AMNH 5730, was purchased by the American Museum of Natural History in 1899. Cope intended to describe the skeleton as well as the skull, but his promised paper never appeared.
Several years after Cope's description, his rival Othniel Charles Marsh published on a sizable lower jaw recovered by John Bell Hatcher in 1889 from Lance Formation rocks in Niobrara County, Wyoming. Marsh named this partial jaw Trachodon longiceps. It is cataloged as YPM 616. As noted by Lull and Wright, this long slender partial jaw shares with Cope's specimen a prominent ridge running on its side. However, it is much larger: Cope's specimen had a dentary, or tooth-bearing bone of the lower jaw, 92.0 centimeters (36.2 in) long, whereas Marsh's dentary was estimated at 110.0 centimeters (43.3 in) long.
A second mostly complete skeleton (AMNH 5886) was found in 1904 in Hell Creek Formation rocks at Crooked Creek in central Montana by Oscar Hunter, a rancher. Upon finding the partially-exposed specimen, he and a companion argued about whether or not the remains were recent or fossil. Hunter demonstrated that they were brittle and thus stone by kicking the tops off the vertebrae, an act later lamented by the eventual collector Barnum Brown. Another cowboy, Alfred Sensiba, bought the specimen from Hunter for a pistol, and later sold it to Brown, who excavated it for the American Museum of Natural History in 1906. This specimen had a nearly complete vertebral column, permitting the restoration of Cope's specimen. In 1907, these two specimens were famously mounted side-by-side in the American Museum of Natural History, under the name Trachodon mirabilis. Cope's specimen is positioned on fours with its head down, as if feeding, because it has the better skull, while Brown's specimen, with a less perfect skull, is posed bipedally with the head less accessible. Henry Fairfield Osborn described the tableau as representing the two animals feeding along a marsh, the standing individual having been startled by the approach of a Tyrannosaurus. Impressions of appropriate plant remains and shells based on associated fossils were included on the base of the group, including ginkgo leaves, Sequoia cones, and horsetail rushes.
American Museum of Natural History, New York City, NY.