CMC VP 7180 mount
Allosaurus fragilis • “Different lizard, fragile”
The most common and lethal apex predator of the Late Jurassic Morrison Formation, hunting with gaping jaws, slashing bites, and robust three-clawed forelimbs.
Mounted fossil skeleton cast (Mongolian Academy of Sciences / RBINS)
Velociraptor mongoliensis • “Swift seizer of Mongolia”
A turkey-sized feathered dromaeosaurid predator of the Gobi Desert, renowned for its hyperextensible sickle-shaped second toe claw and acute binocular hunting vision.
Allosaurus fragilis lived during the Jurassic, while Velociraptor mongoliensis inhabited the Cretaceous. They were separated by roughly 70 million years of deep time and never encountered one another in the ancient world. Both species shared a carnivore diet, occupying comparable trophic levels in their respective food webs. Based on available fossil estimates, Allosaurus fragilis was larger than Velociraptor mongoliensis in both overall length and estimated body mass (approximately 133.33× heavier and 4.25× longer). Estimates vary between individual specimens.
Anatomical dimensions compared on a shared proportional baseline against an adult human (1.8 m / 5.9 ft).
Allosaurus fragilis was longer by approximately 6.5 m.
Allosaurus fragilis stood taller by approximately 2.5 m.
Allosaurus fragilis had a greater estimated mass by 2 tonnes.
Based on available fossil estimates, Allosaurus fragilis was larger than Velociraptor mongoliensis in both overall length and estimated body mass (approximately 133.33× heavier and 4.25× longer). Estimates vary between individual specimens.
Paleontological Note on Mass Estimates: Dinosaur body weights are derived through volumetric laser scanning and femoral circumference scaling equations. Because soft tissue does not fossilize directly, mass values carry statistical margins of uncertainty and represent scientific estimates rather than exact weights.
Direct answers to the most important comparative questions about how these two prehistoric species differed.
Based on available fossil estimates, Allosaurus fragilis was larger than Velociraptor mongoliensis in both overall length and estimated body mass (approximately 133.33× heavier and 4.25× longer). Estimates vary between individual specimens.
Both species shared a carnivore diet, occupying comparable trophic levels in their respective food webs.
Allosaurus fragilis lived during the Jurassic (Late Jurassic, 155–145 Ma), while Velociraptor mongoliensis lived during the Cretaceous (Late Cretaceous, 75–71 Ma).
Fossils of Allosaurus fragilis were recovered from Western United States (Morrison Formation), Portugal, whereas Velociraptor mongoliensis was discovered in Mongolia, Northern China (Gobi Desert).
Allosaurus fragilis had a bipedal locomotion, contrasted with Velociraptor mongoliensis which had a bipedal stance.
Allosaurus fragilis and Velociraptor mongoliensis did NOT live at the same time. They were separated by an immense temporal gulf of approximately 70 million years. Allosaurus fragilis lived and went extinct tens of millions of years before Velociraptor mongoliensis ever evolved.
Side-by-side catalog of verified anatomical measurements and geological records.
| Scientific Parameter | A Allosaurus fragilis | B Velociraptor mongoliensis |
|---|---|---|
| Scientific Binomial | Allosaurus fragilis | Velociraptor mongoliensis |
| Name Meaning | “Different lizard, fragile” | “Swift seizer of Mongolia” |
| Taxonomic Clade / Group | Theropods | Theropods |
| Geological Period | Jurassic | Cretaceous |
| Fossil Time Range | Late Jurassic, 155–145 Ma | Late Cretaceous, 75–71 Ma |
| Diet & Trophic Guild | Carnivore | Carnivore |
| Maximum Length | 8.5 m (27.9 ft) | 2 m (6.6 ft) |
| Standing / Hip Height | 3 m (9.8 ft) | 0.5 m (1.6 ft) |
| Estimated Body Mass | 2 tonnes (2,000 kg) | 0 tonnes (15 kg) |
| Locomotion / Stance | Bipedal | Bipedal |
| Geographic Localities | Western United States (Morrison Formation), Portugal | Mongolia, Northern China (Gobi Desert) |
| Geological Formation | Morrison Formation, Lourinhã Formation | Djadokhta Formation |
| Discovery History | Historical holotype | Historical holotype |
Visualizing both species across the 186-million-year span of the Mesozoic Era.
Allosaurus fragilis and Velociraptor mongoliensis did NOT live at the same time. They were separated by an immense temporal gulf of approximately 70 million years. Allosaurus fragilis lived and went extinct tens of millions of years before Velociraptor mongoliensis ever evolved.
Deep-time perspective: Allosaurus fragilis and Velociraptor mongoliensis were separated by approximately 70 million years. A visitor encountering one would have had no concept of the other.
Comparing the rock strata, paleoclimates, and ancient landscapes where their fossils were entombed.
Western United States (Morrison Formation), Portugal
North America
Mongolia, Northern China (Gobi Desert)
Asia
Stratigraphic Synthesis:
Direct comparisons between extinct animals are inherently shaped by the incomplete nature of the fossil record. Skeletal dimensions reflect holotype or well-preserved paratype specimens, but individual ontogenetic age, sexual dimorphism, and intraspecific variation all influence the true living size of any prehistoric animal.
Body mass estimates shown above represent calculated averages from published volumetric models and biomechanical limb scaling. As modern synchrotron imaging and 3D digital skeletal mounts advance, museum measurements are continually refined.