Othniel Charles Marsh and Edward Drinker Cope were the two most prominent dinosaur specialists of the 1800s—and bitter enemies. They burned through money, funding expeditions to Western badlands, hiring bone collectors away from each other and bidding against one another for fossils in a battle of one-upmanship. They spied on each other's digs, had their minions smash fossils so the other couldn't collect them, and attacked each other in academic journals and across the pages of the New York Herald—making accusations of theft and plagiarism that tarnished them both. Yet between them they named more than 1,500 new species of fossil animals. They made Brontosaurus, Stegosaurus and Triceratops household names and sparked a dinomania that thrives today.
One of Marsh and Cope's skirmishes involved fossil beds in Morrison, Colorado, discovered in 1877 by Arthur Lakes, a teacher and geologist-for-hire. Lakes wrote in his journal that he had discovered bones "so monstrous...so utterly beyond anything I had ever read or conceived possible." He wrote to Marsh, at Yale, to offer his finds and services, but his letters met with vague replies and then silence. Lakes then sent some sample bones to Cope, the editor of American Naturalist. When Marsh got word that his rival was interested, he promptly hired Lakes. Under Marsh's control, the Morrison quarries yielded the world's first fossils of Stegosaurus and Apatosaurus, the long-necked plant eater more popularly known as Brontosaurus.
Lakes spent four field seasons chiseling the most easily reached bones out of the fossil beds. Before he left the area, he allegedly blew up one of the most productive sites—"Quarry 10"—to prevent Cope from digging there.
For 123 years, the site was lost, but in 2002 researchers from the Morrison Natural History Museum used Lakes' field notes, paintings and sketches to find the quarry, expose its original floor and support beams and begin digging once more. "The first things that we found were charcoal fragments: we were digging right below the campfire that Arthur Lakes had built," says Matthew Mossbrucker, director of the museum.
They quickly discovered that at least one misdeed attributed to the feud between Marsh and Cope was probably exaggerated. "It looks like [Lakes] just shoveled some dirt in there," says Mossbrucker. "I think he told people that he had dynamited it closed because he didn't want the competition up at the quarry—playing mind games with Cope's gang."
The reopened quarry is awash in overlooked fossils as well as relics that earlier paleontologists failed to recognize: dinosaur footprints that provide startling new clues about how the creatures lived.
The dig site is perched halfway up the west side of a narrow ridge called the Dakota hogback. The only way up is to walk—over loose rock, past prickly brush and rattlesnakes—with frequent pauses to catch one's breath. On this July morning, Mossbrucker leads six volunteers as they open the quarry for its fourth full modern-day field season. The crew erects a canopy over the pit before forming a bucket brigade to remove backfill that has washed into the hole since last season.