This Dinosaur Fossil Changed the World

The discovery of Deinonychus in 1964 transformed our understanding of wildlife—and helped spawn ‘Jurassic Park.’
(Photo: Courtesy Yale Peabody Museum of Natural History)
Oct 14, 2016· 3 MIN READ
Richard Conniff is the author of House of Lost Worlds: Dinosaurs, Dynasties, and the Story of Life on Earth and other books.

It’s a little embarrassing to admit this, as a wildlife writer, but I didn’t used to think fossils mattered all that much. I wanted to know what was happening to wildlife right now. Fossils were so very then, so 66 million years ago.

The fossil that woke me from my ignorance is named Deinonychus. If that sounds like too much of a mouthful, too much like science, just bear with me for a minute: This story comes with a Jurassic Park plot twist. It also involves correcting a mistake I recently repeated in print.

The Deinonychus story began one afternoon in late August 1964, near Bridger, Montana. John Ostrom, a paleontologist at the Yale Peabody Museum of Natural History, was standing with an assistant on the flank of a conical hill considering sites for the following summer’s fieldwork when the answer appeared before them in the form of a large claw eroding out of the slope just below. They soon unearthed an astonishing foot: Two of the three toes had ordinary claws. But from the innermost toe, a sharp claw, sickle-shaped and 4.7 inches in length, curved murderously up and out. Ostrom gave the new species the name Deinonychus because it means “terrible claw” in Greek.

In the public imagination then, dinosaurs were plodding, thunderous monsters, cold-blooded, swamp bound, and stupid. Even paleontologists had lost interest in these “symbols of obsolescence and hulking inefficiency,” Ostrom’s student Robert T. Bakker later wrote. “They did not appear to merit much serious study because they did not seem to go anywhere: no modern vertebrate groups were descended from them.”

Deinonychus. (Photo: Courtesy Yale Peabody Museum)

But as Ostrom studied the thousand or so bones he excavated, representing at least four individuals, he realized Deinonychus didn’t fit the plodding stereotype. On the contrary, he wrote, this toothy, human-size monster “must have been a fleet-footed, highly predaceous, extremely agile and very active animal, sensitive to many stimuli and quick in its responses.” It wasn’t just Deinonychus. To the horror of his fellow paleontologists, Ostrom in 1969 declared “that many different kinds of ancient reptiles were characterized by mammalian or avian levels of metabolism.” It was the beginning of a radical new way of thinking about dinosaurs—and the beginning of a revolution in how we look at some of our most beloved modern wildlife.

This is where I made my mistake. In my new book, House of Lost Worlds—Dinosaurs, Dynasties, and the Story of Life on Earth, I wrote that Ostrom’s revisionist ideas about dinosaurs spread out from his office at the Peabody Museum to flood popular consciousness, “with countless books, endless computer-generated dinosaurs on television, and multiple iterations of Jurassic Park, the last of these directly inspired by Ostrom and Deinonychus.”

An interview Ostrom gave to The New York Times in 1997 seemed to suggest that novelist Michael Crichton phoned him before writing his 1990 book, Jurassic Park. During their conversation, Ostrom told the Times, Crichton ruefully admitted that he had decided not to use the name Deinonychus because Velociraptora related species roughly the size of a modern turkeysounded more dramatic. Ostrom, a modest, scholarly figure, agreed that the name Deinonychus was, yes, maybe a little too Greek.

But that conversation seems to have taken place years later than I thought, when Crichton was in the middle of writing a sequel, The Lost World. Ostrom himself instigated the conversation, with letters congratulating both Crichton and director Steven Spielberg on the 1993 movie Jurassic Park.

Ostrom invited both men to come to the Peabody to see Deinonychus, “the evidence that apparently started the Jurassic Park ball rolling,” he wrote in the letters. The conversation with Crichton took place soon after. Daniel Brinkman, a paleontologist at the Peabody Museum, recently discovered that correspondence in Ostrom’s papers and just this week put out a correction. It is a small correction perhaps, but it is worth setting the record straight because Jurassic Park in all its iterations has become such a global juggernaut.

It’s worth making the correction as a reminder of just how pervasive Ostrom’s influence was for people everywhere, including Crichton, who had not yet interviewed Ostrom but nonetheless named him not just in the acknowledgments but also in the dialogue of Jurassic Park. It’s also worth thinking about Ostrom’s influence as a reminder that some of his scholarly perceptions are, even today, a little too edgy for the Jurassic Park franchise.

That’s because Ostrom didn’t stop at the idea that dinosaurs could be agile and quick. Beginning in 1970, he also began to catalog similarities in bone structure between Deinonychus and Archaeopteryx, an early bird from 160 million years ago. He went on to publish a series of landmark papers, including “The Ancestry of Birds,” “The Origin of Birds,” and “Archaeopteryx and the Origin of Flight.”

As a result, we now know that all modern birds evolved from the group of bipedal theropod dinosaurs that includes Deinonychus and Velociraptor. The idea that modern birds are living dinosaurs is so commonplace that researchers now debate why they were the only dinosaurs to survive the mass extinction of 66 million years ago. Think about that next time you look at the blue jays or ravens in your backyard. They are dinosaurs. They are alive. It is Jurassic Park out there.

Ostrom also predicted that certain dinosaurs would eventually be covered with feathers. He lived to see this idea proved right by the 1996 discovery of a small theropod dinosaur from China with a mantle of short, dark, feather-like filaments on its back. Further discoveries have since changed our ideas so drastically that current conceptions of Deinonychus depict it covered with almost as many feathers as your average bald eagle.

Think about that when you go see the next Jurassic Park sequel. Steven Spielberg and the rest of Hollywood have gladly followed John Ostrom in making dinosaurs fast and agile. One of these days, they are going to have to follow Ostrom again, giving up that scaly, reptilian, oh-so-1950s science fiction skin and showing us dinosaurs as every schoolchild now knows they existed—with feathers.