Camarasaurus was one of the most common large sauropod dinosaurs in the Late Jurassic of western North America. It lived about 155 to 145 million years ago in floodplain environments preserved today in the Morrison Formation. Its name means chambered lizard, referring to hollow spaces in its vertebrae that helped reduce the weight of its massive skeleton.
Studying Camarasaurus helps paleontologists understand how giant plant-eating dinosaurs moved, fed, grew, and survived in ancient ecosystems.
Unlike some longer and more lightly built sauropods, Camarasaurus had a deep skull, spoon-shaped teeth, a strong neck, and a bulky barrel-shaped body. Its teeth suggest it could crop tougher vegetation than many narrow-toothed sauropods, although it swallowed food without chewing it like mammals do. Air-filled spaces in its bones were connected to a bird-like respiratory system, making the body lighter and improving breathing efficiency.
Fossils of both young and adult Camarasaurus give scientists rare evidence about sauropod growth from juveniles to giants.
Key Facts
- Camarasaurus lived during the Late Jurassic Period, about 155 to 145 million years ago.
- Typical adult length was about 15 to 23 m, depending on species and individual age.
- Camarasaurus mass is estimated at roughly 15,000 to 25,000 kg for large adults.
- Speed relation for a walking animal: v = d/t, where v is speed, d is distance, and t is time.
- Weight near Earth's surface can be estimated by W = mg, with g = 9.8 m/s².
- Its chambered vertebrae contained air spaces that reduced skeletal mass and may have supported efficient breathing.
Vocabulary
- Sauropod
- A group of large herbivorous dinosaurs with long necks, long tails, small heads, and pillar-like legs.
- Morrison Formation
- A Late Jurassic rock unit in western North America that preserves many dinosaur fossils, including Camarasaurus.
- Vertebra
- One of the bones that forms the backbone and protects the spinal cord.
- Pneumatic bone
- A bone containing air-filled spaces that can reduce weight and connect to the respiratory system.
- Herbivore
- An animal that gets its energy mainly by eating plants or plant material.
Common Mistakes to Avoid
- Calling Camarasaurus a carnivore is wrong because its spoon-shaped teeth, body plan, and fossil context show it was a plant-eating sauropod.
- Assuming all sauropods had the same skull and teeth is wrong because Camarasaurus had a deeper skull and broader teeth than many narrow-toothed sauropods.
- Thinking hollow bones made Camarasaurus weak is wrong because pneumatic bones can reduce weight while still staying strong through internal supports.
- Drawing the neck straight upward like a giraffe is often misleading because scientists infer posture from vertebrae, muscle attachment, balance, and joint range rather than from size alone.
Practice Questions
- 1 A Camarasaurus is estimated to have a mass of 18,000 kg. Using W = mg and g = 9.8 m/s², calculate its weight in newtons.
- 2 A Camarasaurus walks 120 m across a floodplain in 80 s. Use v = d/t to find its average speed in m/s.
- 3 Camarasaurus had a deep skull, spoon-shaped teeth, and air-filled vertebrae. Explain how these features could help it feed and move as a giant herbivore.