“Brontosaurus” will always be special to me. For my younger self, especially, the shuffling, swamp-dwelling hulk was an icon of everything dinosaurs were supposed to be—big, scaly, and, most of all, so thoroughly bizarre that they could only have belonged to a primeval past. And, though dead for over 150 million years, “Brontosaurus” lived on in my imagination. From the time I was a toddler, I desperately wanted to meet the gigantic herbivore. In my preschool scribblings, I included a pet “Brontosaurus” in crayoned portraits of my family. I kept it reasonable. I knew we could never afford an eighty-foot dinosaur, so I went with a Bronto roughly the size of a Great Dane. She was big enough to let me ride on her back, but small enough that my parents wouldn’t go poor providing appropriate forage for my friend.
Resuscitating the dinosaur in Crayola colors barely even touched the depths of my dinomania. When my parents drove my siblings and me to Disney World for the first time, I so fiercely harried them about seeing the animatronic “Brontosaurus,” Stegosaurus, and kin at the Exxon-sponsored Universe of Energy attraction that Mom and Dad didn’t even unpack the car before putting us on the right bus to see the dinosaurs. Forget Mickey and Minnie. The jerking, wailing robotic dinosaurs were at the top of my list. And while I would later curse being stuck in the mind-numbingly mundane confines of central New Jersey, my captivity in the suburban sprawl carried at least one advantage. There was scarcely a better place for a young dinosaur fan than the nearby American Museum of Natural History, just over the river in New York City. That’s where I first met my favorite dinosaur.

The museum no longer looks like it did when my parents guided my younger self up to the fourth-floor dinosaur halls in 1988. Today, the white walls, high ceilings, and ample illumination make the skeletons of Tyrannosaurus, Edmontosaurus, Triceratops, and other dinosaur celebrities stand out in sharp contrast from their surroundings. This open, airy vibe was created by a renovation project in the mid-1990s to adjust the prehistoric stars in accordance with new discoveries. Arranged in an evolutionary rank and file, the revised halls are a testament to how much dinosaurs have changed since nineteenth-century naturalists first recognized them. The AMNH dinosaurs stand alert, skeletal heads and tails at attention as if they’re scanning a vanished landscape for food, friend, or foe.

During my early twenties, when I had the freedom to visit whenever I pleased, I took any chance I could get to wander among these skeletons and imagine flesh on their bones. And, as I strolled through those halls, the floors scuffed by the feet of so many youngsters on their first trips into the presence of dinosaurs, what I missed most was the dim, dusty Jurassic Dinosaur Hall that I encountered so many years before. The old dinosaurs were horribly wrong when I viewed them back in the 1980s—awkward aberrations ultimately sent to the scientific trash heap—but that doesn’t diminish my memory of seeing them for the first time. Way back then, in the forbidding gloom of the hall, my imagination gave the bones a thin cast of vitality. The skeletons felt less like perished monuments to paleontology and more like bony scaffolding waiting to be connected by sinew and wrapped in scaly hides. My young mind didn’t see dead dinosaurs, but the osteological architecture of creatures that might walk again.
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I was so consumed by the idea during my first trip to the AMNH that I can hardly remember my parents being there. Standing beneath the prehistoric skeletons, I was entranced. I couldn’t take my eyes off the museum’s “Brontosaurus,” with her neck stretched low, tipped with a moronic blunt skull full of spoon-shaped teeth. I was in the court of the queen of all sauropods—the long-necked, heavy-bodied dinosaurs that were the largest creatures ever to walk the Earth. After all, as my schoolbooks told me, “Brontosaurus” was so massive that her name meant “thunder lizard.” When she walked, it must have sounded like a storm rolling across the Jurassic landscape. I imagined that sound as I admired her skeleton. She seemed poised to step off the platform, duck out the exit, and plod right down to the foliage along Central Park West. In the intense quiet of that moment, I could have sworn that I heard the ethereal remnant of the dinosaur’s breathing. In a place with so many prehistoric bones, there had to be ghosts.

Yes, the old mounts of Tyrannosaurus and other dinosaurs were impressive, too. But they didn’t stick with me quite like the “Brontosaurus.” I couldn’t help but wonder what it would have been like to catch a glimpse of the dinosaur trundling down my street, picking succulent leaves from the oaks of my neighbors’ lawns. I drew sluggish brontosaurs in my school art portfolios, made my plastic sauropod models bask in an improvised mud puddle I created in the driveway’s storm drain, and dreamed of some far-off swamp where the dinosaur might still sun itself, enjoying a reprieve from extinction.
And then I heard the bad news.
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“Brontosaurus” was dead to begin with. My favorite dinosaur wasn’t real, but only a misconstrued amalgamation that had been borne and slaughtered by science. The dinosaur’s true name was Apatosaurus—a creature that paleontologists envisioned as vastly different from my brontosaur. Apatosaurus was not a waterlogged grubber of algae and water lilies, but in fact was a taut, active animal that trod Jurassic floodplains with its neck and extended whiplash tail held high off the ground. “Brontosaurus” as I knew the beast—a hulking pile of flesh and bone that bathed in Jurassic swamps—never actually existed. Almost everything about the monstrous creature—its lifestyle, its skull, and, most regrettably, its name—were human inventions drawn from prehistoric skeletons that actually supported a different form. I had been fooled! The dinosaur I met was a petrified museum zombie, shuffling on even though scientists had shot it down decades before.

You see, the dinosaur’s major makeover wasn’t easy, and it wasn’t fast. I had encountered the brontosaur only as it was slowly fading from books and museum halls. A few years before I made my first museum visit, a groundswell of scientific interest in sauropods, stegosaurs, tyrannosaurs, and their varied kin—given the dramatic title “The Dinosaur Renaissance”—had crushed the image of dinosaurs as stupid, abominable reptiles and recast them as animals that had more in common with birds than with any lizard or crocodylian (a term for the group encompassing alligators, crocodiles, and gharials). The fossil bones were the same as they ever were, but paleontologists saw the petrified remnants in a new light. And in the special case of “Brontosaurus,” the dinosaur’s name, skull...