The Beltway Dinosaur Track

Spectacular dinosaur stomping grounds discovered just outside D.C. No, not politicians.

. . . on a summer day in 2012, a self-taught fossil hunter named Ray Stanford noticed the unmistakable shape of the nodosaur’s track as he drove out of a parking lot at what is now  NASA’s Goddard Space FlightCenter in Greenbelt.

Years of excavation and analysis revealed the contours of that fossil print and dozens more on a single 8.5-foot-long slab of sandstone, Stanford and his colleagues announced Wednesday. It is the largest and most diverse assemblage from the dinosaur age found in the Mid-Atlantic region — and it ranks among the best fossil trackways in the world.

“I like to call it the Rosetta Stone,” said Martin Lockley, a dinosaur track expert at the University of Colorado Denver who participated in the research. The evidence on that slab surface preserves animals as they lived rather than as they died — revealing the ecology of their age in exquisite detail, he said.

And because no prints overlap, Lockley thinks the tracks were laid down and preserved in a “geologic instant” — no longer than a few days but, more likely, during a few hours. In such a contained setting, herbivore and carnivore, reptile and mammal, predator and prey all intersected and potentially interacted.

“One could literally make a movie about everything going on in this slab,” Stanford said.

Sorry, it's behind the paywall at the WaPo, so I'll quote generously.

The excavated slab weighed more than four tons, so the space flight center arranged to have paleontologist Stephen Godfrey make a fiberglass cast that would be easier to study. In fall 2015, the model was installed in Stanford’s basement, where he would meticulously brush fine silt grains into the mold’s dips and divots to reveal the prints. Then came hours of staring at the slab and attempting to divine what happened 110 million years ago from the faint impressions on its surface.

“I could not sleep,” he recounted this week. “It was a time of total amazing discovery.”

“Every time you came down and looked at it and turned the light at a different angle, you’d see something new,” added his wife, Sheila, who often joined him in surveying the slab. Like her husband, she has no formal paleontology training. But she spotted some of the slab’s more interesting features, including the impression of a winged pterosaur dipping its pointed jaw into the earth in search of food, then pushing off from the ground to take flight.

In all, the slab contains about 70 footprints from at least eight types of animal, the Stanfords and their colleagues report in an article published Wednesday in the journal Scientific Reports. Just one other discovery from the Mesozoic era (the 200 million-year span during which dinosaurs roamed Earth) bears as many mammal prints.

Wombat-socho has "Rule 5 Sunday: Eagles With Elbows" ready and waiting.