Certains coelurosaures respiraient comme des oiseaux aquatiques

Since the 19th Century, many scientists, including Thomas Henry Huxley (a supporter of Darwin), saw incredible similarities between birds and the theropod dinosaurs (especially the coelurosaurs). In the late 1960’s, John Ostrom from Yale University noted 22 features in the skeletons of meat-eating dinosaurs that were also found in birds and nowhere else. Subsequent work has found up to 85 characters that tie theropods and birds together.
Like all other reptiles, birds have scales (feathers are produced by tissues similar to those that produce scales, and birds have scales on their feet). Also, birds lay eggs like other reptiles. The soft anatomy (musculature, brain, heart, and other organs) all are fairly similar; birds are more derived in some aspects owing partially to their endothermic metabolism and their ability to fly.
There are numerous skeletal resemblances between birds and other reptiles; these form the basis of the cladistic analyses done by Gauthier and others. Recent new fossil evidences of feathered dinosaurs in China have reinforced this theory, which is now accepted by most scientists.
In a new study published the 7th of November 2007 in the Proceedings of the Royal Society B: Biological Sciences Journal, biologists and palaeontologists from the University of Manchester have found that theropod dinosaurs like the Velociraptor had similar respiratory systems to present-day diving birds, such as marine birds and wildfowl.