Camarasaurus
Camarasaurus (/ˌkæmərəˈsɔːrəs/ KAM-ər-ə-SOR-əs) was a genus of quadrupedal, herbivorous dinosaurs and is the most common North American sauropod fossil. Its fossil remains have been found in the Morrison Formation, dating to the Late Jurassic epoch (Kimmeridgian to Tithonian stages), between 155 and 145 million years ago.
Camarasaurus presented a distinctive cranial profile of a blunt snout and an arched skull that was remarkably square, typical of basal Macronarians.
The name means "chambered lizard", referring to the hollow chambers, known as pleurocoels, in its cervical vertebrae (Greek καμαρα (kamara) meaning "vaulted chamber", or anything with an arched cover, and σαυρος (sauros) meaning "lizard".
The first record of Camarasaurus comes from the spring of 1877 when Mr. Oramel William Lucas of Cañon City, Colorado discovered some large vertebrae at Garden Park, which he sent to Edward Drinker Cope who was based in Philadelphia, Pennsylvania.[1] The original material sent consisted of a partial cervical vertebra, which would become the taxon's namesake, three dorsal vertebrae, and four caudal vertebrae.[2][1] This specimen is now thought to have been composed of several individuals.[2] From these initial fragmentary remains, Cope made his original description of Camarasaurus supremus (“supreme chambered lizard”) and founded the genus; these remains are now in the American Museum of Natural History under the catalogue number AMNH 560.[2] After receiving the original bones, Cope employed collectors who gathered more of the material which was described in 1921 by Henry Osborn and Charles Mook.[2]
The amount of material was great, it composed of several jumbled partial skeletons.[2] It was not all prepared at once, but a considerable amount of it was cleaned up by Jacob Geismar under Cope's direction throughout the 1870s to 1890s.[2] In 1877 a reconstruction of the skeleton of Camarasaurus was painted by Dr. John Ryder on several canvasses, under the direction of Professor Cope who would use them in lectures to impress his audience.[2] This reconstruction would be the first ever made of a sauropod dinosaur, was natural size and represented the remains of a number of individuals. The reconstruction was over fifty feet in length. Cope's collectors sent in more material from 1877 to 1878,[2][3] and as Cope would get more material, he would name taxa based on these newly sent remains. Most of these additional taxa are now considered dubious or synonymous with Camarasaurus.[3] By the end of collecting in Garden Park, at least four individuals and several hundred bones had been found from nearly every part of the skeleton.[2]
