Could Any Human Have Outrun a Tyrannosaurus Rex?

For years, Hollywood has depicted the scary-looking Tyrannosaurus rex as a prehistoric nightmare for anything -- or anyone -- in its path. But new research published in the journal PeerJ claims that this giant dinosaur with small arms probably couldn’t run very fast. Using computer simulations to analyze the brute’s muscular and skeletal strength, the researchers determined that high-speed pursuits were probably not its forte. They estimate that the T. rex probably couldn’t move faster than 12 miles per hour (19 km/h). Given its body mass, they believe that its legs would have snapped under its own weight at higher speeds.

Who's afraid of the big, bad T. rex?

• Scientists previously assumed that the T. rex could run as fast as 45 mph (72 km/h). Research lead William Sellers said the dinosaur “was actually quite slow and therefore not a pursuit predator. Running would have been impossible because its skeleton just isn’t strong enough.”
• Sellers and his team also think that the T. rex would have become less agile with age, and that it had to adapt and change the way it hunted as it aged.
• The study suggests that other large, two-legged dinosaurs -- Giganotosaurus, Mapusaurus and Acrocanthosaurus -- were also not particularly quick.