Allosaurus Facts
Pronunciation: AL-oh-SORE-us
Name meaning: Different Lizard
| 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.
What made Allosaurus distinctive?
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.
Behaviour
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 in Popular Culture
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.
Discovery
Allosaurus was first described by Othniel Charles Marsh in 1877. The original fossils were discovered at Morrison Formation, Colorado, USA.
Allosaurus FAQ
What did Allosaurus eat?
Allosaurus was a carnivore that hunted a wide variety of prey including smaller dinosaurs, fish, and possibly juvenile sauropods. It likely also scavenged carrion when the opportunity arose. Its sharp, serrated teeth were perfect for slicing through flesh and its powerful jaws could crush bones.
How big was Allosaurus?
Allosaurus stood about 3 metres tall at the hip and measured up to 9 metres in length from nose to tail. Adult specimens weighed approximately 2.3 tonnes, making them substantial but relatively lightweight predators thanks to hollow spaces in their bones.
When did Allosaurus live?
Allosaurus lived during the
Late Jurassic period, approximately 155 to 143 million years ago. This was a time when much of what is now western North America was a warm, semi-arid environment with seasonal wet and dry periods.
Where was Allosaurus found?
Most Allosaurus fossils come from the Morrison Formation in the western United States, particularly Colorado, Utah, and Wyoming. Important specimens have also been discovered in Portugal, showing this predator had a wide geographic range during the
Late Jurassic.
How do you pronounce Allosaurus?
Allosaurus is pronounced 'AL-oh-SORE-us', with the emphasis on the first syllable. The name breaks down as 'Allo' (meaning different) and 'saurus' (meaning lizard).
What does Allosaurus mean?
Allosaurus means 'different lizard' in Greek. Palaeontologist Othniel Charles Marsh chose this name in 1877 because he noticed the vertebrae were different from other dinosaurs known at the time, being more lightweight due to hollow spaces.
How fast could Allosaurus run?
Studies of Allosaurus leg bones and body proportions suggest it could reach speeds of up to 40 kilometres per hour in short bursts. This made it fast enough to chase down many potential prey animals, though it probably couldn't maintain top speed for long distances.
What type of dinosaur was Allosaurus?
Allosaurus was a theropod dinosaur, belonging to the family Allosauridae. Theropods were bipedal, predominantly carnivorous dinosaurs that included all the major predatory dinosaurs as well as modern birds.
Was Allosaurus related to birds?
Yes, as a theropod dinosaur, Allosaurus was related to modern birds, though not as closely as some later theropods. All theropods, including Allosaurus, share common ancestry with birds, and many theropod features like hollow bones and three-fingered hands can be seen in birds today.
How many Allosaurus fossils have been found?
Allosaurus is one of the best-represented theropod dinosaurs, with remains from dozens of individuals discovered. The Cleveland-Lloyd Dinosaur Quarry alone has yielded fossils from at least 46 different Allosaurus individuals, making it exceptionally well-known compared to most dinosaur species.
