The Apatosaurus was one of the largest land animals to walk planet Earth. The first fossils of the Apatosaurus appeared in North America and dated back to the late Jurassic period. And this colossal dinosaur was neighbors with some pretty fierce predators like the T-Rex and Carnotaurus.
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Some Quick Facts About the Apatosaurus
| Name | Apatosaurus ajax, “deceptive lizard” |
| Type of dinosaur | Saurischia, sauropod |
| Territory | Grasslands and marshes in North America |
| Size | Large, 69 feet long, 15 feet tall, 80,000 pounds |
| Color | Green to gray-ish blue |
| Interesting Characteristics | One of the biggest land animals of all time, could live to be 100 years old |
| Diet | Herbivore, ate plants and leaves off trees |
| Major Threats | Theropods like the Carnotaurus, Allosaurus, and T-Rex, diseases |
The Apatosaurus was a late Jurassic dinosaur that roamed the marshes of North America. It had a long, powerful neck that could pluck the leaves off tall trees and a 30-foot tail that it used as a defensive weapon. As one of the largest land animals, it was about as long as two school buses!
Are Apatosaurus and Brontosaurus the same?
The Apatosaurus and the Brontosaurus (or thunder lizard) are different dinosaurs, but it’s a common mix-up (even among paleontologists). For almost 100 years, the name Brontosaurus disappeared because many paleontologists believed that the Apatosaurus and the Brontosaurus were the same dinosaurs.
However, after a long study of the fossil records of the Apatosaurus, Brontosaurus, and Diplodocus, paleontologists found that the Apatosaurus was larger and bulkier than the Brontosaurus.
How Big Was The Apatosaurus?
The Apatosaurus was a massive dinosaur. It was so large that it’s considered one of the biggest land animals ever to walk the Earth. It measured almost 70 feet long (about the size of two school buses and weighed about 80,000 pounds! The name Apatosaurus means deceptive lizard or false lizard because paleontologists could not believe how massive this dinosaur was!
What Did The Apatosaurus Eat?
While the Apatosaurus has a long neck, paleontologists believe it mainly dined on low-growing plants like ferns and conifers. Its favorite food was horsetails, which were very abundant in the marshes of North America during the late Jurassic period.
When food was scarce, it sometimes used its long neck to eat the leaves of tall trees. Despite its massive size, the Apatosaurus was an herbivore, like other similar sauropod dinosaurs like the Brachiosaurus, and never ate meat.
What Other Dinos Did The Apatosaurus Live With?
As a North American dino found in the Morrison Formation in the late Jurassic, the Apatosaurus had plenty of friendly and not-so-friendly neighbors. It lived alongside friendly long-necked dinosaurs like:
- Camarasaurus
- Diplodocus
- Brachiosaurus
- Mosasaurs
- Barosaurus
It often competed for food. Even though the Apatosaurus was large, it still had to be on the lookout for apex predators that roamed North America during that time, like the mighty T-Rex.
When And Where Were the First Apatosaurus Fossils Found?
Many of the fossil remains of the Apatosaurus skeleton appeared in the Morrison Formation that spanned states like Wyoming, Colorado, Oklahoma, and Utah. Miners, not paleontologists, discovered the first Apatosaurus bones.
In 1877, two miners found the colossal fossil remains and contacted Othniel Charles Marsh from Yale to collect the amazing fossil specimens.
The first fossil records in the Rocky Mountain foothills were a partial Apatosaurus skull, braincase, and vertebrae. Today, many of these first fossils live at the Carnegie Museum of Natural History and the American Museum of Natural History.
4 Fun Apatosaurus Facts
1. The tail of the Apatosaurus was used as a bullwhip. Apatosaurus had a tail that was about 30 feet long, and it would crack it like a bullwhip to scare off potential predators.
2. They laid giant eggs. As a colossal dinosaur, it also means it laid giant eggs. The average size of an Apatosaurus egg was about one foot long, or about the same size as a basketball!
3. They could live up to 100 years old. If they could survive attacks from predators, the Apatosaurus could live up to 100 years old. To put that into perspective, theropod dinos like the T-Rex rarely reached 30 years old.
4. Its name means false lizard because paleontologists couldn’t believe its massive size. When Othniel Charles Marsh studied the bones, he couldn’t believe their size and thought they were so large that they belonged to an enormous sea creature. Hence, the name false lizard.