A dinosaur ‘tombstone’ lurks underneath New Jersey

The big sky country of the western North America is a world-renowned dinosaur playground. Household-name dinosaurs like Tyrannosaurus rex and Triceratops, to the lesser known duck-billed Maiasaura once ate, slept, laid eggs, and pooped in this expansive region of plains, rivers, lakes, and mountains. 

However, the eastern half of the continent shouldn’t be left out when the urge to hunt for fossils strikes. Take, for instance, the often maligned state of New Jersey. The Garden State is home to a rock layer that is essentially a geological dinosaur tombstone, preserving remnants of the planet Earth at a rather momentous time. 

“What we have is a bone bed, and we can see it’s right at the end of the Cretaceous Period,” Kenneth Lacovara, a geologist and paleontologist at Rowan University tells Popular Science. “So what we really have is the best window into the last moments of the dinosaurs that exist on the planet.”

Among his larger finds, Lacovara led the team that discovered the giant, 60-ton behemoth Dreadnoughtus in Argentina that was featured in 2022’s Jurassic World: Dominion. When not out finding new Titanosaurs, Lacovara and other paleontologists have spent the last 17 years closer to his home, combing this end-Cretaceous bone bed square meter by square meter. They’ve recorded over 100,000 fossils, representing more than 100 species of plants and animals.

“All [of the fossils] from this end-Cretaceous boundary layer represent the extinction of the dinosaurs,” says Lacovara.

Now, at a new museum and fossil park, citizen scientists can take to the dirt themselves to help put together the puzzle of how, when, and why the largest animals to ever walk the Earth met their demise. 

‘Toaster oven to pizza oven’: The day the dinosaurs died 

Over the past several decades, paleontologists have uncovered several more details on the death of the dinosaurs 66 million years ago. Someday during the spring, an asteroid about 6 to 12 miles-wide slammed into the waters off of present-day eastern Mexico’s Yucatán Peninsula.

“From where I am in New Jersey, your first indication that something has gone wrong would have been at about eight minutes and 37 seconds later. At our location, there would have been a magnitude 10.3 earthquake. A 10.3 earthquake is bigger than the Earth can make. The Earth has to be rung from the outside like a bell to get an earthquake that big, since rocks don’t have enough strength to build that much stress up before they snap,” explains Lacovara.

That unprecedented earthquake would have spurred mega tsunamis with 2-mile high waves. It also would have been strong enough that 90-ton Sauropods and other mega dinosaurs would have been knocked off their feet–to their deaths.

“If you’re a huge Sauropod dinosaur and you fall down, you probably die, you probably burst,” says Lacovara.

After the asteroid’s impact, the resulting crater would have been about 12 times the size of the state of Massachusetts. The impact likely sent up trillions of millimeter sized capsules of debris dripping with energy, like the fire coming off of a rocket. 

“Within the first hour after the impact, global temperatures get up somewhere between toaster oven and pizza oven,” says Lacovara. “So, if you’re on the surface of the Earth that day, if you had no place to hide, you’re toast.”

Fan favorite dinosaurs Tyrannosaurs rex and Triceratops ultimately died out either quickly from the impact itself or more slowly from the food shortages caused by debris blocking the sunlight, or other planetary upheaval. However, not all of the dinosaurs really disappeared.

[ Related: How do we know what dinosaurs looked like? ]

Dinosaurs are birds and birds are dinosaurs

The first Jurassic Park novel and subsequent 1993 film introduced a general audience to the idea that birds are dinosaurs. According to Lacovara, there’s now a generation of working planetologists that credit Jurassic Park with sparking their interest in paleontology and science. Additionally, we have even more supporting evidence for the fact that some dinosaurs evolved into birds.

“Birds are clearly dinosaurs,” says Lacovara. “To be considered a dinosaur, you have to have the first dinosaur for an ancestor, and birds do. It’s the same reason why we’re mammals. We all have the first mammal for an ancestor, and so does kangaroo, and so does blue whale, and so does a hamster.”

It’s the same with birds from tiny swallows up to giant flamingos or blue herons. They’re dinosaurs that share the common ancestor–two-legged dinosaurs known as theropods, which include giants like Tyrannosaurs and smaller raptors. Or as Lacovara puts it, “a hummingbird is a dinosaur, to the same degree that T. Rex, or a stegosaurus is a dinosaur.”

Paleontologists also have a better record of how feathers evolved. Their first function was not flight, but rather insulation. The feathers adorning extinct dinosaurs like Yutyrannus huali and various raptor species likely would have sported something similar to the downy feathers on baby birds, instead of the flat interlocking feathers that evolved later on. 

“It’s only later that some of these feathered, non-avian dinosaurs began,” says Lacovara. “They had an arboreal lifestyle, and they began jumping from tree to tree.”

Why we love dinosaurs

While paleontologists have made leaps and bounds in understanding both how dinosaurs lived and died, there is still a lot to learn about all extinct living things, from ammonites on up to the mighty megalodon. 

To help discover even more in the fossil record, digging enthusiasts can visit the new Edelman Fossil Park & Museum of Rowan University in Sewell, New Jersey. About 30 minutes outside of Philadelphia, the site offers the opportunity to not see some bones up close and also dig for their own discoveries in a former quarry. The park is somewhat of a real Jurassic Park–only without the threat of Velociraptors. 

With a stream of films, documentary series such as Walking with Dinosaurs, and books, the lure of dinosaurs endures. That love goes deeper than the fun of digging up dinosaur bones, fossilized poop, or Megaolodon teeth. 

“I think it’s for a bunch of reasons. For one, they were real. This isn’t Godzilla or Bigfoot. These things were real,” says Lacovara.

As for kids, arguably the target audience for the real Edleman Fossil Park & Museum and fictional Jurassic Park, Lacovara believes that dinosaurs often give children their first taste of expertise.

“For a number of years, they’ve been told about everything by everybody. ‘Here’s how to use a fork, here’s how to lock the door, here’s how to tie your shoes.’ Now, for the first time, they’re telling other people things that those other people don’t know,” he says.

Kids also make excellent amateur fossil hunters, and taking that expertise and applying it to the field can be quite exciting. Digging for fossils anywhere also opens exciting avenues to discoveries both big and small–from small seashell-like brachiopods in the damp soil to shark teeth and bigger bones. 

“When a kid comes to the fossil park and finds that little clam shell or shark tooth with their own hands, that’s a legitimate discovery. No human has ever seen that thing before. It’s a little piece of information no human has ever known that thing before,” says Lacavora. “So they become a legitimate explorer at that moment. And who doesn’t want to be that?”

[ Related: Celebrate 30 years of Jurassic Park with these recent dinosaur discoveries. ]

What dinosaurs tell us about the future 

While dinosaur bones and their extinction story might seem relegated to the past, natural history museums and paleontology offer us an important window to the future. Lacovara cites the quote attributed to Winson Churchill, “The farther back you can look, the farther forward you can see,” as an example of the good that paleontology gives to the world and how natural history museums offer an important conservation message. 

“It’s a lens through which we can contextualize our present moment to hopefully help us make better choices for the future,” he says. “People love what they know, and people protect what they love. So our mission is to connect people with both their ancient planet, and their present planet.”

It’s a planet that has faced at least five waves of mass extinction and is potentially in the cold grips of a sixth, one that is driven by human activity and not a force of nature like a giant asteroid strike or volcanic eruptions. 

“We’ve been here a very, very short amount of time. And what makes us think that we have some privileged position, that our place in the future is guaranteed? It is not, and the kind of future that we would wish for our posterity is only going to happen if we work for it,” says Lacovara. “It is not going to happen by accident.”

 

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