Apatosaurus

Apatosaurus means 'deceptive lizard'. You may know it as Brontosaurus. Apatosaurus lived 150 million years ago in North America. This enormous creature was 23 meters long and weighed 25 tons.

Apatosaurus was huge sauropod approaching 23 meters. It reached its maximum size in about 10 years. Its family includes some of the longest creatures ever to walk the earth, including Diplodocus, Supersaurus, Suuwassea. 

It was believed that sauropods like Apatosaurus were too massive to support their own weight on dry land.Apatosaurus was the second most common sauropod in the Morrison Formation ecosystem, after Camarasaurus. It may have been a more solitary animal than other Morrison Formation dinosaurs.

Nathan Myhrvold carried out a computer simulation of the tail, which in diplodocids like Apatosaurus was a very long, tapering structure resembling a bullwhip. This computer modeling suggested that sauropods were capable of producing a whip-like cracking sound of over 200 decibels, comparable to the volume of a cannon.