Cretaceous
Tyrannosaurus rex
carnivore · United States, Canada
Comparative anatomy
Compare dinosaurs
Place two or three species side by side to compare their bodies, time ranges, locations, evidence, and position in the evolutionary tree.
Cretaceous
Triceratops horridus
herbivore · United States
At a glance
Side-by-side evidence
| Feature | Tyrannosaurus rex | Triceratops horridus |
|---|---|---|
| Classification | Tyrannosauroidea → Tyrannosauridae → Tyrannosaurus → Tyrannosaurus rex | Ceratopsoidea → Ceratopsidae → Triceratops → Triceratops horridus |
| Geological age | 68–66 Ma | 68–66 Ma |
| Diet | carnivore | herbivore |
| Length | ~12.3 m | ~8.5 m |
| Mass | ~8,000 kg | ~7,000 kg |
| Location | United States, Canada | United States |
| Locomotion | bipedal | quadrupedal |
| Fossil completeness | excellent | excellent |
| Description year | 1905 | 1889 |
| Key traits | Broad, deep skull strengthened by fused and interlocking bones; Thick, serrated teeth with rounded, bone-resistant cross sections; Forward-facing eyes and a wide field of binocular overlap; Short but muscular forelimbs ending in two functional fingers; Large hip and thigh musculature powering the hind limbs; Long, heavy tail balancing the head and torso; Major skull and limb proportion changes during growth | Very large skull with a narrow, toothless beak; Two elongated brow horns and a shorter nasal horn; Solid parietal-squamosal frill edged by epiossifications; Dense dental batteries with replacement teeth stacked beneath working teeth; Robust neck and fused front vertebrae supporting the head; Sprawling-to-upright forelimb posture with the palms facing inward; Powerful hind limbs and a relatively short, heavy tail |
Scaled silhouettes
Relative length
Tyrannosaurus rex~12.3 m
Triceratops horridus~8.5 m
Shared ancestry
Most recent common ancestor
DinosauriaThe most recent common ancestor is the closest ancestral node shared by every selected path. This simplified result follows Dinosauria Tree’s current tree hypothesis.
9 levels from root9 levels from root
Time overlap
Geological timeline
235 Ma200 Ma145 Ma100 Ma66 Ma
Tyrannosaurus rex
Triceratops horridus
Ranges are approximate and do not imply the selected animals met.