Science, Tech, Math › Animals & Nature John H. Ostrom Share Flipboard Email Print John H. Ostrom. Animals & Nature Dinosaurs Paleontologists Basics Carnivores Dinosaurs & Birds Herbivores Marine Reptiles Prehistoric Mammals Amphibians Birds Habitat Profiles Mammals Reptiles Wildlife Conservation Insects Marine Life Forestry Evolution View More By Bob Strauss Science Writer B.S., Cornell University Bob Strauss is a science writer and the author of several books, including "The Big Book of What, How and Why" and "A Field Guide to the Dinosaurs of North America." our editorial process Bob Strauss Updated March 06, 2017 Name: John H. Ostrom Born/Died: 1928-2005 Nationality: American Dinosaurs Discovered or Named: Deinonychus, Sauropelta, Tenontosaurus, Microvenator About John H. Ostrom Nowadays, pretty much all paleontologists agree that birds descended from dinosaurs. However, that wasn’t the case in the 1960's, when John H. Ostrom of Yale University was the first researcher to propose that dinosaurs had more in common with ostriches and swallows than with snakes, turtles and alligators (to be fair, the heavyweight American paleontologist Othniel C. Marsh, who also taught at Yale, had proposed this idea in the late 19th century, but he didn't have enough evidence at his disposal to carry the weight of scientific opinion). Ostrom's theory about the dinosaur-bird evolutionary link was inspired by his 1964 discovery of Deinonychus, a large, bipedal raptor that displayed some uncannily birdlike characteristics. Today, it's (pretty much) an established fact that Deinonychus and its fellow raptors were covered with feathers, not a popular image a generation ago, and one that even current dinosaur enthusiasts have difficulty accepting. (In case you were wondering, those "Velociraptors" in Jurassic Park were really modeled after the much bigger Deinonychus, disregarding the fact that they were portrayed with green reptilian skin rather than feathers.) Fortunately for him, Ostrom lived long enough to learn about the trove of indisputably feathered dinosaurs recently discovered in China, which cemented the dinosaur-bird connection. When he discovered Deinonychus, Ostrom opened the dinosaur equivalent of a hornet's nest. Paleontologists weren't used to dealing with muscular, man-sized, predatory dinosaurs--as opposed to familiar, multi-ton carnivores like Allosaurus or Tyrannosaurus Rex--which prompted speculation about whether an ostensibly cold-blooded reptile could engage in such energetic behavior. In fact, Ostrom's student Robert Bakker was the first paleontologist to forcefully propose that all theropod dinosaurs were warm-blooded, a theory that's currently on only slightly shakier ground than the dinosaur-bird connection. By the way, he wasn't responsible for either discovering or naming this dinosaur, but the type species of Utahraptor (U. ostrommaysorum) was named after John Ostrom and Chris Mays, a pioneer in animatronic dinosaurs.