The great sauropods
Brachiosaurus, Diplodocus and Apatosaurus walk the floodplains of North America.
- When
- Known to
- ± 5 million years
- Era
- Jurassic, Mesozoic
The Late Jurassic is the peak of sauropod diversity and size. Diplodocus stretched over 25 metres, mostly neck and tail; Brachiosaurus carried its shoulders higher than its hips to browse treetops. Their bones show growth rates closer to birds and mammals than to reptiles — these animals reached full size in a few decades, not centuries.