Camarasaurus grandis

Overview

Camarasaurus grandis is a sauropod dinosaur known from the Late Jurassic Morrison Formation. Researchers study a body extending from a small head, through the neck, to a massive trunk and four legs. Bones from several regions reveal the connections within an enormous body.^[1]

Key facts

The inventory of YPM1905 lists a skull, neck, back and tail vertebrae, shoulder and limb bones, and foot elements. Evidence from several body regions gathered in one specimen list provides a basis for comparing their connections.^[1]

Time and place

Material from the Late Jurassic Morrison Formation has been studied. The Jurassic as a whole spans roughly 200–140 million years ago. Several Camarasaurus specimens from the same formation have been used to investigate distribution and age.^[1][3]

The time range describes source context, not the complete duration of this species.

Size, form and skeleton

The body extends from a small head through the neck and massive trunk to four legs and a tapering tail. Genus-level descriptions discuss thick upper and lower jaws and forelimbs more slender than the hind limbs. Species-specific bone inventories can be compared with shared features of the genus.^[1]

Skeleton GMNH 101 at the Gunma Museum of Natural History is presented as approximately 13.7 m in total length. A 2002 study used its proportions as a comparative reference when estimating the sizes of other sauropods.^[8]

Habitat and reproduction

How did the massive body connect with four legs? Examining the shoulder, pelvis, and front and rear limb bones separately helps us picture the structures supporting the trunk. Moving to foot articulations reveals small structures beneath the large body.^[1][2]

Fossil discovery

A study of distribution and geological age compiled the head, vertebral, and limb inventory of YPM1905 and treated YPM1901 as separate material. Research on hand and foot articulations in Camarasaurus followed in 2015. Different body regions lead to different research questions.^[1][2]

References

1. Study of Camarasaurus distribution in the Morrison Formation and geological age
2. Tschopp et al. (2015) — Articulation of the hand and foot bones of Camarasaurus
3. International Commission on Stratigraphy (2024) — Geological time chart
4. Evers (2024) — The mandible and feeding of Glyptops
5. International Commission on Stratigraphy (2024) — Geological time chart
6. Study of Camarasaurus distribution in the Morrison Formation and geological age
7. International Commission on Stratigraphy (2024) — Geological time chart
8. Buffetaut et al. (2002) — Comparing skeletal sizes of Thai sauropods and Camarasaurus

Research questions

Can the head, trunk, and feet be compared from the same perspective? Bone inventories reveal the evidence available for each region, while hand and foot research examines connections among small bones. Understanding a large body involves changing the scale of observation.^[1][2]

Observation

Move your gaze from the small head to the neck and large trunk. Examine where the front and rear limbs connect with the trunk, followed by the tapering tail, to reveal the overall construction.^[1]