Allosaurus Facts
| Diet | Carnivore |
| Height | 3m |
| Length | 9m |
| Weight | 2.3 tonnes |
| Speed | 40 km/h |
| Environment | Land |
| Era | Jurassic |
| Period | Late Jurassic |
| Type | Theropod |
| Location | North America And Portugal |

| Diet | Carnivore |
| Height | 3m |
| Length | 9m |
| Weight | 2.3 tonnes |
| Speed | 40 km/h |
| Environment | Land |
| Era | Jurassic |
| Period | Late Jurassic |
| Type | Theropod |
| Location | North America And Portugal |
Allosaurus was one of the most fearsome theropod dinosaurs of the Late Jurassic period, prowling the ancient landscapes of what is now North America and Portugal between 155 and 143 million years ago. This powerful predator was perfectly built for hunting, standing about 3 metres tall at the hip and measuring up to 9 metres in length. Despite its impressive size, Allosaurus was surprisingly lightweight for its bulk, thanks to hollow spaces in its vertebrae that reduced its weight whilst maintaining strength.
The most distinctive features of Allosaurus were its massive skull, which could reach over 80 centimetres long, and its fearsome array of sharp, serrated teeth designed for slicing through flesh. Its powerful hind legs propelled it at speeds of up to 40 kilometres per hour, whilst its relatively small but muscular arms ended in three-fingered hands equipped with large, curved claws. Two prominent ridges above its eyes gave Allosaurus a particularly menacing appearance.
As an apex predator, Allosaurus likely hunted a variety of prey, from smaller dinosaurs to potentially even juvenile sauropods. Evidence suggests it may have been both an active hunter and a scavenger, using its powerful jaws to crush bones and its razor-sharp teeth to strip meat from carcasses. The abundance of Allosaurus fossils, particularly from the famous Cleveland-Lloyd Dinosaur Quarry in Utah, has made it one of the best-understood theropod dinosaurs.
Allosaurus had distinctive horn-like ridges above its eyes, giving it a particularly fierce appearance. Its skull was unusually large relative to its body, and its arms, though small, were notably more robust than those of later theropods like Tyrannosaurus.
Allosaurus likely hunted both alone and possibly in loose groups, as suggested by multiple individuals found together at some fossil sites. Evidence of healed injuries on Allosaurus bones suggests they engaged in fierce battles, either with prey or with each other over territory and mates.
Allosaurus has appeared in numerous films and documentaries, including the BBC's 'Walking with Dinosaurs' series, and is a popular dinosaur in video games and children's books due to its fearsome appearance and well-documented fossil record.
| Phylum | Chordata |
| Class | Saurischia |
| Order | Avetheropoda |
| Family | Allosauridae |
| Genus | Allosaurus |
Allosaurus was first described by Othniel Charles Marsh in 1877. The original fossils were discovered at Morrison Formation, Colorado, USA.