Acrocanthosaurus (or "acro" for short) ruled what is now North America during the early Cretaceous Period. This muscular predator had tall spines on its back and used them for protection and to gore enemies in fights. Usually just a few bites from acro's sharp, serrated teeth could wound other dinos so badly they would bleed to death.
Slice & Dice: Acrocanthosaurus' strong jaws were built for stripping meat from bone. This dino had 68 curved teeth that were serrated, like a saw, on both sides for making clean slices. Its teeth were thin, however, and couldn't crunch through bone.
Slash & Grab: Unlike many predatory dinosaurs, acro could use its arms to hold onto victims as it bit into them. This reptile could also slash at enemies with the three sickle-shaped claws that capped its fingers.
Muscle Lizard[]
This dino's skull measured up to 4.5 feet in length.
Acrocanthosaurus had a long row of spines that measured up to two feet tall growing out of its backbone all the way from its neck to its tail. Some scientists think these spines formed a sail on the dinosaur's back to help regulate body temperature, but others believe that they created a sort of "super spine" to anchor the beast's huge back muscles. Such muscles would have given acro the power to wrestle big prey to the ground.
Predator's Footsteps: A fossilized set of acro footprints were found behind those of a huge plant-eater named pleurocoelus. They show that the predator carefully stalked its prey from behind, then pounced as it neared its victim, similar to the way a tiger hunts today.
Sure Sniffer: Like its ancestor, allosaurus, acro had a highly developed sense of smell. When live prey was hard to find, this ancient reptile could easily track down the scent of dinosaur carcasses.
Timeline[]
Acrocanthosaurus lived 115 to 105 million years ago, during the Cretaceous Period.