Scientists have long thought that the dinosaur's lungs as the bird's lungs. The closest relationship between the two. But the Oregon State University, Ruben and others of a study of dinosaur fossils soft tissue samples and found that the dinosaur's lungs more like a modern E-type mesh. Birds is through a special "mobile systems" breathe, regardless of breath or breathing, the system will supply to the lungs. The E-type head with a membrane lung, breathing, muscle movement so that rib cavity to expand, inhaled air. This is the so-called "rib breathing." Mammalian structure also completely different with the former two. Breathing mammals, by the diaphragm to assist. Breath, the diaphragm arch; inhale, the diaphragm smoothing, so that the pressure to the lungs when inhaling are smaller. Ruben, who found the dinosaur seems to not only divide the lungs, as well as diaphragm. Dinosaurs at rest speculation that they use rib breathing, diaphragmatic breathing with activities. As the oxygen-rich, so their activities are more capable than any living reptiles can do.