| Diet | Omnivore |
| Height | 2m |
| Length | 6m |
| Weight | 440 kg |
| Speed | 60 km/h |
| Environment | Land |
| Era | Cretaceous |
| Period | Late Cretaceous |
| Type | Theropod |
| Location | Mongolia |
Gallimimus was a large theropod dinosaur that roamed the ancient landscapes of Mongolia during the Late Cretaceous period, between 93.9 and 72.2 million years ago. Despite being a theropod—the group that includes fearsome predators like Tyrannosaurus—Gallimimus was remarkably different from its carnivorous cousins, resembling a massive, featherless ostrich more than a typical meat-eating dinosaur.
Standing about 2 metres tall at the hip and measuring up to 6 metres in length, Gallimimus was built for speed rather than strength. Its long, powerful legs could potentially propel it at speeds of up to 60 kilometres per hour across the Mongolian plains. The dinosaur's most distinctive feature was its elongated neck topped with a small, toothless head and a distinctive bulbous structure at the base of its skull—a feature that inspired its specific name 'bullatus', meaning 'bubble-like'.
Unlike many theropods, Gallimimus was an omnivore with a varied diet. Its beak-like mouth was perfectly adapted for picking up small prey such as insects, lizards, and mammals, whilst also being capable of processing plant material, eggs, and possibly filtering small organisms from water. This dietary flexibility likely contributed to its success in the diverse ecosystems of Late Cretaceous Asia.
Gallimimus remains one of the best-known members of its group, thanks to remarkably complete fossils discovered by Polish-Mongolian expeditions in the 1960s. These specimens have provided paleontologists with detailed insights into the anatomy and likely behaviour of these fascinating 'ostrich dinosaurs'.
Gallimimus had an extremely long neck with a small, toothless head featuring a distinctive bulbous structure at the base of the skull. Its body was built like a giant ostrich, with long, powerful legs designed for running and relatively small arms with clawed hands.
Gallimimus likely lived in herds and used its exceptional speed to escape from predators across the open plains of ancient Mongolia. Its large eyes suggest it had good vision for spotting both food and danger, whilst its long neck allowed it to reach food at various heights.
Gallimimus gained fame through its memorable appearance in the 1993 film Jurassic Park, where a herd of these dinosaurs was shown stampeding across Isla Nublar.
| Phylum | Chordata |
| Class | Saurischia |
| Order | Avetheropoda |
| Family | Ornithomimidae |
| Genus | Gallimimus |
Gallimimus was first described by Rinchen Barsbold, Halszka Osmólska, and Ewa Roniewicz in 1972. The original fossils were discovered at Gobi Desert, Mongolia.
