This summer, children and adults alike will have their fascination with dinosaurs rekindled thanks to the June 12 release of “Jurassic World,” the fourth installment in the popular “Jurassic Park” movie franchise that first captivated the country in 1993. Countless South Jersey residents will be among those who will flock to theaters to soak in Hollywood’s sci-fi take on these gigantic prehistoric beasts, marveling at the idea that such incredible creatures once roamed the earth. However, little do many of these local movie-goers realize, such majestic animals used to inhabit the very land they live on today. In fact, the first complete dinosaur skeleton ever unearthed was discovered in Haddonfield, NJ, spurring the beginning of the modern era of dinosaur paleontology.

A Curious Discovery

In the early 19th century, Haddonfield was largely an agricultural area, and it wasn’t uncommon for land owners to dig into the ground to harvest rich organic soil known as marl or greensand. The year was 1838, as the story goes, when a Haddonfield farmer named John Hopkins stumbled upon some unusually large bones in a makeshift marl pit on his farm.

According to Ted Daeschler, a paleontologist at the Academy of Natural Sciences in Philadelphia, very little was known about dinosaurs at the time, aside from a few fragmentary bits of knowledge gleaned from some isolated teeth and bones that had been discovered in England.

“The term dinosaur was just staring to be used,” explained Daeschler. “The knowledge base was very limited, but they realized there were these big reptilian forms that had lived in the distant past. That all sort of kicked in during the 1840s and so.”

The typical attitude of the era among the general public was to treat such fossils as curiosities to be admired rather than researched.

“It was, ‘Oh, wow, this is curious. I’m going to add it to my cabinet of curiosities,’ and that was that,” Daeschler said.

That’s exactly what Hopkins did, and two decades passed before Academy of Natural Sciences member William Parker Foulke learned of Hopkins’ discovery and looked at it with a scientific eye. After talking to Hopkins, Foulke did some digging at the spot where the bones were initially spotted, and he uncovered a number of additional fossils. Foulke got in touch with Joseph Leidy, an anatomist with the Academy, and in 1858, the fossils were fully excavated.

Revolutionary Science

Between the bones that Hopkins initially found around 1838 and the rest of the fossils dug up 20 years later, the Academy of Natural Sciences ended up with around 30 percent of the skeleton of the creature, which was named Hadrosaurus foulkii in honor of Foulke. Although the world had never seen something like Hadrosaurus foulkii before, it was clear to the scientists at the Academy what they had found.

Portrait of Joseph Leidy with Hadrosaurus bone fossil. Stereograph.

Joseph Leidy poses with a Hadrosaurus bone fossil.

“Joseph Leidy had no problem at all saying, ‘Aha, here is one of these dinosaur-type animals,’” Daeschler said.

Even today, 30 percent of a dinosaur skeleton is considered to be a very valuable find, but in the dawn of paleontology, retrieving 30 percent of a dinosaur’s remains was particularly remarkable and provided plenty of material to work with.

“The beauty there, as any anatomist can tell you, is if you have a left femur, well, you know what the right femur is going to look like,” Daeschler explained. “Although they only found part of a skeleton, it was way better than the single bones that had been found previously, which is the more common way to find any fossils.”

Leidy worked with the Academy curator Edward Drinker Cope and British sculptor Benjamin Waterhouse Hawkins to create a mounted display of the bones.

“For the first time, there was enough of the skeleton that they could actually get some ideas about the proportions of the body,” Daeschler said. “That was just revolutionary, to be able to do that. It was sort of the beginning of the modern era of dinosaurs.”

The Hadrosaurus foulkii skeleton debuted at the Academy in 1868 as the first mounted dinosaur skeleton in the world. Although the dinosaur was displayed standing on its rear legs, a posture which paleontologist’s today believe to be incorrect, and the head of the Hadrosaur was largely a fabrication, the display was a huge scientific breakthrough and drew massive crowds.

“Basically, they could reconstruct this animal from the neck down quite well,” Daeschler said. “There were enough pieces of the hips and the legs and the arms and the backbone, but the tricky part was, there was very little of the head, and that’s where the early reconstructions of Hadrosaurus had to make some educated guesses.”

Leidy and his team blended aspects of an iguana skull with characteristics of a tuatara, another type of lizard, to come up with the faux Hadrosaurus skull.

“Today, we have a newer mount of Hadrosaurus, one with updated posture, and we’ve also updated the skull, but it has to be realized, it’s still our best guess,” Daeschler said. “But we can make a much better guess now because we know the group. We know Hadrosaurs more generally because there’ve been other discoveries made, particularly in the American west. Although we can’t say specifically what the skull of Hadrosaurus was, we can get a lot closer than they did in 1868.”

One of a Kind

Although other species of Hadrosaurs have been discovered throughout the country since Foulke’s find in Haddonfield, Hadrosaurus foulkii remains the only one of its kind. Daeschler says there have been additional “bits and pieces of Hadrosaurs” found in New Jersey that are most likely Hadrosaurus foulkii, but they can’t definitely be tabbed as such.

Hadrosaurus - Walters

Hadrosaurus foulkii was an herbivore that spanned 23 feet long and weighed an estimated 7,000 pounds.

“For reasons of nomenclature, we often just put them in the family,” Daeschler said of the isolated Hadrosaur bones discovered throughout the Garden State.  “There are not enough of them to say a specific species, but you would guess that it would be Hadrosaurus foulkii.”

They key in differentiating dinosaur species within a general family is the skull.

“What you need are heads. You really need heads,” Daeschler emphasized.  “Think about, like, the family that we call bovids, which are cows and all the cow relatives, like bison and water buffalo. If you give me a bone of a cow or a bison, I’m going to have a hard time telling them apart if it’s a leg bone or something, but if you give me a head, it’s very easy.”

Although it can be hard to tell species apart without a skull, there are a number of distinguishing characteristics of the Haddonfield skeleton that indicate Hadrosaurus foulkii is its own species.

“People are confident that Hadrosaurus foulkii is a unique species, despite the fact that we don’t have a lot of the head, because of the fact that there are some unique features in the body,” Daeschler said.

Float and Bloat

While comprised of solid land today, South Jersey was a shallow sea environment during the days of dinosaurs.

“If you look at Barnegat Bay and the barrier islands, and if you go back 80 million years, all of that was up in Haddonfield and Camden,” Daeschler said. “In other words, the shore line was inland. Since then, New Jersey has sort of built up by slow accretion of sediments.”

The marl material that Hadrosaurus foulkii was found in typically forms in mucky bay areas, which further solidifies the theory that this particular dinosaur met a watery demise.

“It appears that here’s a Hadrosaur that maybe drowned, or more likely, ‘float and bloat,’ which means a dead Hadrosaur got washed out in a flood, kind of drifted a little bit out into a bay, and kind of started to decay, so it floated and then sank,” Daeschler explained.

That means Hadrosaurus foulkii likely lived a bit west of modern day New Jersey, perhaps in southeastern Pennsylvania.

“It might have actually lived more in Pennsylvania and washed out,” Daeschler said.

Hanging with Hadrosaurs

Hadrosaurus foulkii wasn’t the only dinosaur to spend time in our area. Millions of years ago in the Cretaceous Period, one of the creatures hanging with (and hunting for) Hadrosaurus foulkii was Dryptosaurus, another New Jersey dinosaur discovered in Barnsboro in 1866.

“Dryptosaurus was a meat eater, which makes it particularly cool,” Daeschler said. “It’s sort of a primitive relative of Tyrannosaurus rex, but it’s not as big. It had big hand claws, kind of like the Velociraptors on “Jurassic Park,” a big mean dino.”

Dryptosaurus and Hadrosaurus - 1905

This 1905 illustration by Joseph Smit depicts two New Jersey dinosaurs, Dryptosaurus and Hadrosaurus, duking it out.

Aside from Hadrosaurus foulkii and Dryptosaurus, there haven’t been any other complete dinosaur finds in New Jersey, but isolated bones of other types of Hadrosaurs have been discovered.

“Back in the 40s, there were parts of another duck-billed dinosaur that were found, but it’s just parts of two legs and hips,” Daeschler said. “It’s been described as a different kind of Hadrosaur than Hadrosaurus foulkii.”

The fact that the dinosaur remains found in New Jersey to date have primarily been Hadrosaurs is indicative of the area’s environment millions of years ago.

“Maybe it’s no surprise that duck-billed dinosaurs, Hadrosaurs, are the most common thing, and we have found bits and pieces of lots of them, because of something about this environment at the time,” Daeschler said. “Maybe it was the duck-billeds that were living and dying along the shorelines, so they tend to be preserved in these deposits which are the near-shore deposits, whereas the other groups of dinosaurs, they may have been living up further in the inland areas of this land mass, and their bones didn’t have much of a chance to get buried anywhere.”

The remains of dinosaurs that lived to the immediate west of New Jersey didn’t have much of a chance to be preserved. While land in New Jersey was building up, Pennsylvania was eroding.

“Pennsylvania has been eroding away for 200 million years,” Daeschler said. “It hasn’t been accumulating sediments, so anything that lived where Pennsylvania or New York is, unless they got washed out into what is now the coastal plain, they’re not going to be preserved. But, guaranteed, there’s a hell of a lot more within the rocks of that coastal plain.”

Future Finds

Whenever the next big dinosaur discovery in New Jersey takes place, there’s a good chance it will be an entirely new species of creature within a larger existing family known to scientists thanks to other discoveries across the country. For example, there have been a wide array of Ceratopsian dinosaurs—horned animals, like Triceratops—found throughout the U.S., but a Ceratopsian has yet to make its way to the surface in New Jersey.

“Were there any Ceratopsians in the ecosystems that were supporting other dinosaurs in New Jersey? I think you might say, yeah, it wasn’t just Dryptosaurus and Hadrosaurus,” Daeschler said. “There were lots of other kinds, but we haven’t found them.”

One of the reasons there haven’t been any recent breakthrough dinosaur discoveries in New Jersey is because people don’t dig in the same way that they used to. Hadrosaurus foulkii was found in an era where digging was done by hand.

“They were digging in and getting down into the green sands and stuff, and we haven’t tended to do as much of that, especially by hand,” Daeschler said. “When you’re digging by hand, you notice what you’re going through more than when you’re digging with heavy equipment, like to build the New Jersey Turnpike or something like that. Things don’t always get noticed and preserved. There’s still some good fossils coming out from New Jersey, but we’re not digging the big holes like we used to.”

Even so, it’s only a matter of time until another historical discovery is made.

“There’s no doubt at all that there’re more dinosaurs buried under southern New Jersey, especially the Haddonfield area,” Daeschler said.