Brachiosaurus dinosaurs lighter than believed

Appears In:

Dinosaurs much smaller than once believed, scientist says

Researchers study modern animals' body mass, extrapolate that to fossils.

World's oldest dinosaur may have been discovered

Tanzanian specimen lived around 243 million years ago, 10 million years before the emergence of other "true" dinosaur species

Brachiosaurus dinosaurs lighter than believed

A brachiosaurus skull sits in the Natural History Museum in Berlin, Germany, on July 13, 2007. The centerpiece is the world's largest mounted dinosaur skeleton, a brachiosaurus brancai, at more than 50-feet long and 42-feet tall.

Alexander Hassenstein

AFP/Getty Images