But it was the sauropods, like Brontosaurus, Diplodocus, and Brachiosaurus, who reached enormous proportions. Like the theropods, these titans used air sacs to breathe and had light, hollow bones.

The Brontosaurus and Brachiosaurus are perhaps the most famous of the sauropods – dinosaurs defined by their long necks, long tails, small heads and four pillar-like legs. But these particular ...