Gallimimus

Gallimimus bullatus

Resembling a giant ostrich, Gallimimus bullatus was the largest of the bird-mimic dinosaurs, reaching about 6 meters and near 440 kilograms. Its long, slender legs made it one of the swiftest dinosaurs, with running speeds estimated around 56 kilometers per hour. A toothless beak and lightly built skull point to an omnivorous diet of plants, insects, and small animals. Rinchen Barsbold and colleagues described it in 1972 from the Gobi Desert of Mongolia, where it lived during the Late Cretaceous, roughly 100 to 66 million years ago. It remains the best-known member of the ornithomimosaur group.

Gallimimus was the largest ornithomimid, resembling a giant ostrich. It was one of the fastest dinosaurs, estimated to run at speeds up to 56 km/h. Its diet likely included plants, insects, and small animals.

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Physical Description

Measurement Value Human Scale
Length 6.0 m roughly the length of a large SUV
Height 1.9 m —
Weight 440 kg about 6 adult humans

Diet & Feeding

Omnivore

Gallimimus had a varied diet that included both plants and animals. Omnivorous dinosaurs were versatile feeders, able to exploit multiple food sources, which gave them an advantage in changing environments.

Time Period

Cretaceous Late Mesozoic Era

Gallimimus lived during the Cretaceous Late period of the Mesozoic Era, approximately 100.5 to 66.0 million years ago.

The final age of dinosaurs, featuring iconic species like Tyrannosaurus rex, Triceratops, and Velociraptor. Dinosaurs reached their peak diversity before the catastrophic asteroid impact at the Chicxulub crater ended the Mesozoic Era.

Discovery & Naming

Named By Rinchen Barsbold et al.
Discovery Year 1972
Discovery Location Gobi Desert, Mongolia

Classification

Dinosauria → Saurischia → Theropoda → Ornithomimosauria → Gallimimus

Bird-mimic dinosaurs

Fast-running theropods with toothless beaks resembling modern ostriches. Likely omnivorous. Could reach speeds estimated at 50-60 km/h.

Size Comparison

At 6.0 meters long and 440.0 kg, Gallimimus was roughly the length of a large SUV and about 6 adult humans.

Other dinosaurs from the same period:

Abavornis Abavornis bonaparti Abdarainurus barsboldi Abditosaurus kuehnei Abelichnus astigarrae Abelisauridae

Quick Facts

Classification Ornithomimosauria
Geologic Period Cretaceous Late
Diet Omnivore
Size 6.0m long, 1.9m tall, 440.0kg

Related Dinosaurs

Ornithomimus Cretaceous Late
Omnivore

Frequently Asked Questions

When did Gallimimus live?
Gallimimus lived during the Cretaceous Late period (Mesozoic Era, 100.5–66.0 million years ago).
What did Gallimimus eat?
Gallimimus was a omnivore.
How big was Gallimimus?
Gallimimus was approximately 6.0 meters long, 1.9 meters tall, weighed around 440.0 kg.
When was Gallimimus discovered?
Gallimimus was first described in 1972 by Rinchen Barsbold et al., with fossils found in Gobi Desert, Mongolia.
What type of dinosaur was Gallimimus?
Gallimimus belonged to the Ornithomimosauria group, which is part of the larger Theropoda clade.
Where were Gallimimus fossils found?
Fossils of Gallimimus were found in Gobi Desert, Mongolia.
What is the scientific name of Gallimimus?
The scientific name of Gallimimus is Gallimimus bullatus.

Compare with Similar Dinosaurs

Gallimimus vs Ornithomimus

Explore More

Cretaceous Late
All dinosaurs from this period
Ornithomimosauria
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Omnivores
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