Plateosaurus was one of the most important plant-eating dinosaurs of the Late Triassic Period, living about 214 to 204 million years ago. It belonged to an early group of dinosaurs called sauropodomorphs, which later gave rise to the gigantic long-necked sauropods. Fossils of Plateosaurus are especially valuable because many skeletons have been found, allowing paleontologists to study its body shape, growth, and behavior in unusual detail.
Its long neck, small head, strong hind limbs, clawed hands, and balancing tail make it a key example of early dinosaur evolution.
Key Facts
- Plateosaurus lived during the Late Triassic Period, about 214 to 204 million years ago.
- Adult body length was commonly about 5 to 10 m, depending on age and individual growth.
- Plateosaurus was a sauropodomorph, an early relative of later giant sauropods such as Apatosaurus and Brachiosaurus.
- Growth rate can be estimated from fossils using growth rate = change in body size / change in time.
- Walking speed can be estimated with speed = distance / time, using trackway spacing when footprints are preserved.
- Its long tail helped balance the body, so torque from the front of the body was partly countered by torque from the tail.
Vocabulary
- Plateosaurus
- Plateosaurus was a Late Triassic herbivorous dinosaur and one of the best-known early sauropodomorphs.
- Sauropodomorph
- A sauropodomorph is a dinosaur from the lineage that includes Plateosaurus and the later long-necked sauropods.
- Late Triassic
- The Late Triassic was the final part of the Triassic Period, when dinosaurs were becoming more diverse on land.
- Fossil
- A fossil is preserved evidence of ancient life, such as a bone, tooth, footprint, or plant impression.
- Paleontology
- Paleontology is the scientific study of ancient life using fossils and geological evidence.
Common Mistakes to Avoid
- Calling Plateosaurus a sauropod, because it was a sauropodomorph rather than a true giant sauropod like Diplodocus.
- Assuming all Plateosaurus individuals were the same size, because fossils show that individuals grew at different rates and reached different adult sizes.
- Drawing Plateosaurus as a slow, heavy quadruped only, because evidence suggests it had powerful hind limbs and may often have moved on two legs.
- Treating one fossil skeleton as a perfect blueprint, because paleontologists compare many fossils and account for missing, distorted, or damaged bones.
Practice Questions
- 1 A Plateosaurus skeleton is estimated to be 8 m long. If the tail makes up 40 percent of the body length, how long is the tail?
- 2 A young Plateosaurus increased from 200 kg to 800 kg over 12 years. What was its average growth rate in kg per year?
- 3 Plateosaurus had a long neck, small head, strong hind limbs, clawed hands, and a long tail. Explain how these features could help it feed, move, and stay balanced in a Late Triassic environment.