Majungasaurus crenatissimus was a large meat eating dinosaur that lived on the island of Madagascar about 70 to 66 million years ago, near the end of the Cretaceous Period. It is one of the best studied theropods from the Southern Hemisphere because scientists have found many bones, including skulls, vertebrae, limbs, and teeth. Its fossils help paleontologists understand how island environments shaped dinosaur evolution.
Majungasaurus matters because it shows that not all predatory dinosaurs looked like Tyrannosaurus, even when they filled a similar top predator role.
Key Facts
- Majungasaurus lived about 70 to 66 million years ago during the Late Cretaceous Period.
- Its adult length was about 6 to 7 m, with a deep skull, short snout, and very small forelimbs.
- Majungasaurus belonged to Abelisauridae, a group of theropods common on southern continents.
- It lived in Madagascar, which was isolated from many other landmasses during the Late Cretaceous.
- Simple time span calculation: duration = 70 Ma - 66 Ma = 4 million years.
- Estimated speed can be compared with v = d/t, where v is speed, d is distance, and t is time.
Vocabulary
- Theropod
- A group of mostly meat eating dinosaurs that walked on two legs, including Majungasaurus, Allosaurus, and birds.
- Abelisaurid
- A theropod dinosaur from the family Abelisauridae, known for deep skulls, reduced arms, and many fossils from southern continents.
- Late Cretaceous
- The final part of the Cretaceous Period, lasting from about 100.5 to 66 million years ago.
- Endemic
- A species is endemic when it is found naturally in only one geographic region.
- Paleontology
- The scientific study of ancient life using fossils, rock layers, and evidence from past environments.
Common Mistakes to Avoid
- Calling Majungasaurus a Tyrannosaurus relative is wrong because it belonged to Abelisauridae, a different theropod group with a separate evolutionary history.
- Drawing long useful arms is wrong because Majungasaurus had extremely reduced forelimbs that were tucked close to the body.
- Assuming it lived in mainland Africa is wrong because its fossils are from Madagascar, which was an island environment during the Late Cretaceous.
- Treating every bite mark as proof of active hunting is wrong because bite marks can also come from scavenging, feeding behavior, or interactions after death.
Practice Questions
- 1 Majungasaurus lived from about 70 Ma to 66 Ma. How many million years did this time interval last?
- 2 If an adult Majungasaurus was 6.5 m long and a scale drawing shows it as 13 cm long, what scale in meters per centimeter does the drawing use?
- 3 Explain why the isolation of Madagascar could lead to dinosaurs with unusual body forms compared with relatives on other landmasses.