Title | Lung structure and ventilation in theropod dinosaurs and early birds |
Publication Type | Journal Article |
Year of Publication | 1997 |
Authors | Ruben, J, Jones, TD, Geist, NR, Hillenius, WJ |
Journal | Science |
Volume | 278 |
Pagination | 1267-1270 |
Type of Article | Journal Article |
ISSN | 0036-8075 |
Abstract | Reptiles and birds possess septate lungs rather than the alveolar-style lungs of mammals. The morphology of the unmodified, bellowslike septate lung restricts the maximum rates of respiratory gas exchange. Among taxa possessing septate lungs, only the modified avian flow-through lung is capable of the oxygen-carbon dioxide exchange rates that are typical of active endotherms. Paleontological and neontological evidence indicates that theropod dinosaurs possessed unmodified, bellowslike septate lungs that were ventilated with a crocodilelike hepatic-piston diaphragm, The earliest birds (Archaeopteryx and enantiornithines) also possessed unmodified septate lungs but lacked a hepatic-piston diaphragm mechanism. These data are consistent with an ectothermic status for theropod dinosaurs and early birds. |
URL | <Go to ISI>://WOS:A1997YG04300037 |
DOI | 10.1126/science.278.5341.1267 |