Brachiosaurus
Brachiosaurus altithorax • "Arm Lizard with Deep Chest"
Brachiosaurus was a very tall, long-necked sauropod from Late Jurassic North America. Its forelimbs were longer than its hind limbs, giving it a high-shouldered build; the best-known material is incomplete, so full-body reconstructions involve estimates.
- Length
- ≈22 m
- Weight
- ≈45.0 t
- Diet
- Herbivore
- Danger
- ★★★★★
Overview
One of the tallest and most iconic sauropods of the Jurassic. Unlike most other long-necked dinosaurs, its front legs were longer than its hind legs, giving it a majestic giraffe-like posture to browse high Jurassic conifer trees 13 meters above the forest floor.
“Brachiosaurus had a heart estimated to weigh over 200 kg (440 lbs) in order to generate the massive blood pressure required to pump blood up its 9-meter vertical neck.”
Key facts
Strengths
- Colossal physical mass (45 metric tonnes) makes it virtually immune to solo predators
- Can trample apex theropods effortlessly beneath its colossal front feet
- Monopolizes high-canopy conifer foliage out of reach of all other herbivores
Weaknesses
- Slow locomotion sprint speed (cannot chase or evade quickly)
- Enormous caloric intake required (consumed hundreds of kilograms of foliage daily)
- Large turning radius in confined spaces
Natural weapons
- 45-tonne kinetic stomp force capable of pulverizing any predator
- Massive tree-trunk front forelimbs with heavy thumb claws
- High-altitude vantage point 13 meters above ground level
- Heavy muscular tail capable of sweeping away medium theropods
Movies vs. science
Myth: Often shown rearing up on its hind legs to reach even higher branches.
Reality: Its center of mass was located over its front legs, making rearing structurally impossible and unnecessary given its 13m height.
Size & simulator stats
The Natural History Museum estimates about 22 m in length, but notes that complete skeletons are lacking and reconstructions partly use a related species.
- Length
- 22 m
- Height
- 13 m
- Weight
- 45.0 t
Illustrative simulator values (not measured biology)
See how Brachiosaurus measures up in the sourced size comparison chart.
Habitat
Lush semi-arid floodplain forests and river valleys dominated by colossal conifer trees, ginkgoes, and cycads.
North America; known Brachiosaurus fossils were found in the western United States.
Diet
High-browser feeding on pine cones, conifer needles, ginkgo leaves, and tree ferns with spoon-shaped chisel teeth.
Herbivore. Its long neck and teeth are consistent with feeding on plants; exact feeding height and diet are reconstructed from anatomy.
Fossils & discovery
First described from United States & Tanzania in 1900 (Morrison Formation (Grand River Valley, Colorado)).Brachiosaurus had a heart estimated to weigh over 200 kg (440 lbs) in order to generate the massive blood pressure required to pump blood up its 9-meter vertical neck.
Research sources
Sources checked on by the Dinosaurs Names Editorial Team. Editorial policy
Gallery
Related dinosaurs
Battle Arena
Can anything beat Brachiosaurus?
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