Well, we recently discovered that they had feathers. Now it turns out they breathed like birds, too: velociraptors and some other theropods (the raptors' family, made up of meat-eating two-legged dinos) had a breathing system similar to modern geese and penguins. The dinos had not only lungs, but also air sacs attached to their spines. This increased breathing efficiency, making the beasts faster and hardier.
"We think that the dinosaurs would have had an effective respiratory system, as we know that the bird system is highly efficient and has a lot of adaptations that enable the birds to fly, which is very energetically expensive," study leader Jonathan Codd of the University of Manchester (UK) told National Geographic. Added co-author Phil Manning, also of the University of Manchester, "The maniraptoran dinosaurs were a pretty effective group of predators. These were nasty, toothy, powerful, and fleet-of-foot predators. If they were around today, I somewhat doubt that we would have made it up the evolutionary ladder to see them."
