Camarasaurus supremus

Lore & Background

The first life-sized reconstruction of a sauropod skeleton was actually made for Camarasaurus (then called Morosaurus) in 1878 by Othniel C. Marsh's team, not for C. supremus in 1877 by John A. Ryder. The first specimens of Camarasaurus supremus known to science were found in the spring of 1877 by Oramel William Lucas, a schoolteacher in Cañon City. Lucas collected several large vertebrae at Garden Park in Colorado. Lucas sent the fossils to Edward Drinker Cope in Philadelphia. Cope identified them as belonging to a new species, which he named Camarasaurus supremus in a paper published on August 23, 1877 and the fossils were deposited in Cope's private collection.

Reader's Guide

Camarasaurus supremus is significant as the type species of the genus Camarasaurus and as one of the largest sauropods known from the Morrison Formation. Its discovery in 1877 by Edward Drinker Cope occurred at the outset of the Bone Wars, a period of intense scientific rivalry between Cope and Othniel Marsh. Despite being the first discovered species of Camarasaurus, C. supremus is relatively rare and poorly known, with only 4.5% of Camarasaurus specimens identified as belonging to the species. Its fossils are known only from the uppermost layers of the Morrison Formation, and it coexisted with other giant dinosaurs such as Maraapunisaurus fragillimus. The species has four junior subjective synonyms, all named by Cope, and there is some uncertainty regarding whether C. lentus and C. supremus are distinct species. The first life-sized reconstruction of a sauropod skeleton was created for C. supremus in 1877 by John A. Ryder under Cope's guidance. C. supremus may have weighed more than Brachiosaurus, which is found in older parts of the Morrison Formation.

Did You Know?

• Camarasaurus supremus was discovered by Edward Drinker Cope in 1877 at the outset of the Bone Wars.
• It is the largest species of Camarasaurus, 20% to 50% larger than other species in linear dimensions.

Discovery Amid the Bone Wars

Camarasaurus supremus entered the fossil record during one of paleontology's most competitive eras. In early 1877, David Baldwin, working as a collector for Othniel Charles Marsh, stumbled upon enormous bones atop a hill called "The Nipple" in Garden Park, Colorado. Neither Baldwin nor Marsh showed interest in the find. The bones were later encountered by local teacher Oramel W. Lucas on a hunting excursion, who promptly wrote to Edward Drinker Cope. Cope offered Lucas payment to excavate the material. The first shipment arrived as a theropod jaw, but the second contained vertebrae from a far larger animal that Cope described as the most bulky land animal known. In a hastily written 1877 paper, Cope named the specimen Camarasaurus supremus, the genus name meaning 'chambered lizard' for the hollow spaces in its vertebrae and the specific epithet meaning 'supreme.' Lucas and his brother Ira continued sending additional bones to Cope until 1884, assembling most of a skeleton. The original eight vertebrae, now catalogued at the American Museum of Natural History, remain the type material for the species.

Anatomy and Feeding Ecology

Camarasaurus supremus was a notably bulky sauropod, distinguished by a proportionally wide rib cage and a skull that was larger and more robustly constructed than those of its sauropod relatives. Its powerful jaws generated high bite forces, and its dentition—thirteen to fourteen spoon-shaped teeth per side of the upper jaw and thirteen per side below—was tilted forward and rapidly replaced throughout life. These features point to a selective feeding strategy, with the animal likely browsing vegetation at heights between two and five meters above the ground. In terms of size, C. supremus was considerably larger than the more common C. lentus, which measured around fifteen meters in length. The species is thought to have been the youngest within the genus, concentrated near the top of the Morrison Formation. Individuals ranged from a presumed embryo to an animal estimated at roughly forty years old, one of the oldest ages ever documented for a dinosaur. Skin impressions on one specimen and evidence of arthritis and bite marks on others offer rare glimpses into the physical realities of sauropod life.

Taxonomic Journey and Classification

The taxonomic history of Camarasaurus supremus reflects the chaotic pace of nineteenth-century paleontology. Cope named the genus in 1877 from Garden Park material, but his rival Marsh quickly described a new genus, Morosaurus, from Como Bluff, Wyoming specimens. Over time, Morosaurus and its species were reassigned into Camarasaurus, consolidating what had been split by rivalry rather than genuine anatomical distinction. Today, four species are commonly recognized within the genus: C. supremus, C. grandis, C. lentus, and C. lewisi. Camarasaurus belongs to the sauropod subgroup Macronaria, and some paleontologists have placed it alongside genera such as Tehuelchesaurus and Lourinhasaurus within the family Camarasauridae. C. supremus is considered the largest of the four and may represent the youngest species in the genus, predominantly occurring in the uppermost layers of the Morrison Formation. The type material—eight vertebrae that likely came from two different individuals—remains the formal reference point for the species, a modest foundation for what is now one of the best-understood sauropods.

Fossil Record and Early Reconstructions

Camarasaurus supremus benefits from an exceptionally rich fossil record, with over 530 specimens recovered from Morrison Formation rocks across the western United States, including several nearly complete skeletons. From 1909 onward, Carnegie Quarry at what is now Dinosaur National Monument yielded multiple largely complete specimens, some of which—including a nearly intact skull—still rest embedded in the quarry wall. Perhaps the most remarkable early legacy of this genus is a life-sized drawing created around 1879 by zoologist John A. Ryder under Cope's direction. Measuring sixty-eight feet in length, it was painted on linen sheets and represents the oldest known skeletal reconstruction of any sauropod. Because little was known of the skull at the time, Ryder depicted it with long, sharp teeth, reflecting the assumption that sauropods were carnivorous. The drawing was not published until 1914, when Charles Craig Mook reproduced it at a much smaller scale. In 1885, Charles Frederick Holder produced what may be the first life restoration of a sauropod, showing Camarasaurus with a short trunk-like snout and very slender limbs and tail—images that bear little resemblance to the bulky animal later revealed by the fossil record.