Scott Hanko
Apatosaurus excelsus
Apatosaurus ( /əˌpætɵˈsɔrəs/), also known by the popular but scientifically redundant synonym Brontosaurus, is a genus of sauropod dinosaur that lived from about 154 to 150 million years ago, during the Jurassic Period (Kimmeridgian and early Tithonian ages). It was one of the largest land animals that ever existed, with an average length of 23 m (75 ft) and a mass of at least 23 metric tons (25 short tons). The composite term Apatosaurus comes from the Greek names apate (ἀπάτη)/apatelos (ἀπατηλός) meaning "deception"/"deceptive" and sauros (σαῦρος) meaning "lizard"; thus, "deceptive lizard". Othniel Charles Marsh gave it this name because he regarded the chevron bones as similar to those of some mosasaurs, members of a group of prehistoric marine lizards.
The cervical vertebrae were less elongated and more heavily constructed than those of Diplodocus and the bones of the leg were much stockier (despite being longer), implying a more robust animal. The tail was held above the ground during normal locomotion. Like most sauropods, Apatosaurus had only a single large claw on each forelimb, with the first three toes on the hind limb possessing claws.
Fossils of these animals have been found in Nine Mile Quarry and Bone Cabin Quarry in Wyoming and at sites in Colorado, Oklahoma and Utah, present in stratigraphic zones 2-6.
Apatosaurus was a large, long-necked quadrupedal animal with a long, whip-like tail. Its forelimbs were slightly shorter than its hindlimbs. One measurement places the total length of the species Apatosaurus louisae at 22 m (72 ft).
It was roughly the weight of four elephants. One specimen of A. excelsus was estimated to weigh 25,952 kg (57,210 lb); estimates for A. louisae were 20,600 kg (45,000 lb)[3] and 22,407 kg (49,400 lb).[6] Other estimates of the body mass of adult Apatosaurus species range from 18,000 kg (40,000 lb)[7] to 35,000 kg (77,000 lb). A microscopic study of Apatosaurus bones concluded that the animals grew rapidly when young and reached near-adult sizes in about 10 years.
The skull was small in comparison with the size of the animal. The jaws were lined with spatulate teeth, which resembled chisels, suited to an herbivorous diet. Like other sauropods, the vertebrae of the neck were deeply bifurcated; that is, they carried paired spines, creating a wide and deep profile for the neck. The apparently massive neck was, however, filled with an extensive system of weight-saving air sacs. Apatosaurus, like its close relative Supersaurus, is notable for the incredibly tall spines on its vertebrae, which make up more than half the height of the individual bones. Also unusual among diplodocids is the shape of the tail, which is comparatively thin in breadth and short in height, a profile caused by the vertebral spines decreasing in height rapidly the farther they are from the hips. Apatosaurus also had very long ribs compared to most other diplodocids, giving it an unusually deep chest. The limb bones were also very robust.
American Museum of Natural History, New York City, NY
Apatosaurus excelsus
Apatosaurus ( /əˌpætɵˈsɔrəs/), also known by the popular but scientifically redundant synonym Brontosaurus, is a genus of sauropod dinosaur that lived from about 154 to 150 million years ago, during the Jurassic Period (Kimmeridgian and early Tithonian ages). It was one of the largest land animals that ever existed, with an average length of 23 m (75 ft) and a mass of at least 23 metric tons (25 short tons). The composite term Apatosaurus comes from the Greek names apate (ἀπάτη)/apatelos (ἀπατηλός) meaning "deception"/"deceptive" and sauros (σαῦρος) meaning "lizard"; thus, "deceptive lizard". Othniel Charles Marsh gave it this name because he regarded the chevron bones as similar to those of some mosasaurs, members of a group of prehistoric marine lizards.
The cervical vertebrae were less elongated and more heavily constructed than those of Diplodocus and the bones of the leg were much stockier (despite being longer), implying a more robust animal. The tail was held above the ground during normal locomotion. Like most sauropods, Apatosaurus had only a single large claw on each forelimb, with the first three toes on the hind limb possessing claws.
Fossils of these animals have been found in Nine Mile Quarry and Bone Cabin Quarry in Wyoming and at sites in Colorado, Oklahoma and Utah, present in stratigraphic zones 2-6.
Apatosaurus was a large, long-necked quadrupedal animal with a long, whip-like tail. Its forelimbs were slightly shorter than its hindlimbs. One measurement places the total length of the species Apatosaurus louisae at 22 m (72 ft).
It was roughly the weight of four elephants. One specimen of A. excelsus was estimated to weigh 25,952 kg (57,210 lb); estimates for A. louisae were 20,600 kg (45,000 lb)[3] and 22,407 kg (49,400 lb).[6] Other estimates of the body mass of adult Apatosaurus species range from 18,000 kg (40,000 lb)[7] to 35,000 kg (77,000 lb). A microscopic study of Apatosaurus bones concluded that the animals grew rapidly when young and reached near-adult sizes in about 10 years.
The skull was small in comparison with the size of the animal. The jaws were lined with spatulate teeth, which resembled chisels, suited to an herbivorous diet. Like other sauropods, the vertebrae of the neck were deeply bifurcated; that is, they carried paired spines, creating a wide and deep profile for the neck. The apparently massive neck was, however, filled with an extensive system of weight-saving air sacs. Apatosaurus, like its close relative Supersaurus, is notable for the incredibly tall spines on its vertebrae, which make up more than half the height of the individual bones. Also unusual among diplodocids is the shape of the tail, which is comparatively thin in breadth and short in height, a profile caused by the vertebral spines decreasing in height rapidly the farther they are from the hips. Apatosaurus also had very long ribs compared to most other diplodocids, giving it an unusually deep chest. The limb bones were also very robust.
American Museum of Natural History, New York City, NY