Acrocanthosaurus

Acrocanthosaurus was about 11 to 11.5 metres (36 to 38 ft) long and weighed between 4.4 and 8.4 metric tons (4.9 and 9.3 short tons).31

No, T. rex was generally heavier and more robust. While length estimates are similar, T. rex was typically bulkier than Acrocanthosaurus.2

Acrocanthosaurus was a meat-eater that preyed on dinosaurs larger than itself, like the sauropod Pleurocoelus, as well as ornithopods and ankylosaurs.23

Acrocanthosaurus lived during the Early Cretaceous Period, about 110 million years ago, which is 45 million years before T. rex appeared.21

Scientists are unsure what the tall spines on its back were for. They might have helped control body temperature, store fat, or communicate with others.23

Acrocanthosaurus probably could not run very fast. Its leg bones suggest it was not a fast runner, and it attacked like a modern lion but at a slower pace.32

Acrocanthosaurus fossils have been found in Oklahoma, Texas, Wyoming, and Maryland in the United States. It lived across much of North America.31

No, Acrocanthosaurus belonged to a different family of dinosaurs. It was more closely related to Allosaurus than to T. rex.2