Dinosaurs Breathed like Birds

Big meat-eating dinosaurs had a complex system of air sacs similar to the setup in today's birds, according to an investigation led by Patrick O'Connor of Ohio University. The lungs of theropod dinosaurs -- carnivores that walked on two legs and had bird-like feet -- likely pumped air into hollow sacs in their skeletons, as is the case in birds.

Look here, here, and, definitively, here.

It seems that dinosaurs are becoming something rather different than what they were when I was very young. How wonderful! :D