Digging for dinosaurs: Naturalis on expedition in Wyoming

Naturalis Biodiversity Center is well known for harboring some exceptional dinosaur fossils, the most famous being T. rex Trix. With dinosaurs as popular as ever among young and old, the dinosaur exhibit is a favorite of the public and draws a lot of visitors. Currently, Naturalis presents a world first: a herd of five Triceratops is on display as a temporary exhibition until the end of August. These dinosaurs were excavated by Naturalis between 2015 to 2019, adding even more dinosaurs to the museum. However, there’s more reasons to dig up dinosaurs than just to put them on display.

The current excavation

A team of paleontologists and preparators of Naturalis’ dinosaur lab is currently excavating a fossil site in Wyoming (USA), known as the Jurassic Mile. This rich locality provides amazing fossils every year, with a variety of different dinosaur species. Panos Skandalos, project coordinator dinosaurs at Naturalis, is excited to be excavating here: “Wyoming is one of the most famous places around the world to excavate dinosaurs. Due to our collaboration with the Children’s Museum of Indianapolis, we were able to work on this locality. The paleontologists of Naturalis couldn’t miss the opportunity to work with our fantastic colleagues at this extraordinary site.”

Quite an adventure

Wyoming is one of the least densely populated states in the US. One of those reasons is the harsh weather. In winter, with the heavy snow and fierce winds, excavating becomes practically impossible. This means the team has to be very careful scheduling their excavations, according to Erwin Zethof, dinosaur preparator at Naturalis: “The best time to dig therefore is in summer, when the weather is nice and not too wet. Still this means we are often working in temperatures of more than 30 degrees Celsius, and sometimes we are hit by heavy thunder and hail storms. Quite an adventure when you are camping outside.”

The team’s efforts in the heat have not been in vain this year. It has been a very productive season, says a delighted Zethof: “We uncovered many fossils. Up to five hundred of several species of dinosaurs. Mostly long necked sauropods. Which species exactly still has to be determined. First we have to prepare the bones back in the Dinolab at Naturalis. Some bones are easily identifiable, while others have more subtle features that we have to take into account. Other than bones we also found teeth of both herbivorous and carnivorous dinosaurs and even dinosaur tracks.”

Why not just buy dinosaurs?

As Zethof and Skandalos can attest, digging up dinosaurs is hard work. So why does Naturalis undertake these excavations every year when it's also possible to buy a fully prepared dinosaur? Naturalis’ general director Edwin van Huis has a very simple answer. “Naturalis doesn’t have the money to buy dinosaurs at an auction. They are very expensive. The other day, a Stegosaurus was sold for 45 million dollars at auction”, he says.

But there’s more to it than simply a question of money. Excavating dinosaurs has a high scientific value for the institute. And it’s a lot more fun, says Van Huis. “It’s much more exciting to look for dinosaurs yourself and dig them up. Moreover, this way we learn a lot more about the dinosaurs and their environment. This year, the paleontologists are examining the geology of the area and researching the mammals that inhabited the area together with the dinosaurs. Very little is known about them, and I expect some important scientific publications to emerge from it.”

The relevance of dinosaurs

Although the main focus of the excavation is to study the Jurassic giants themselves and the world they lived in, paleontology has more relevance than just researching the past. “The study of the biodiversity of our planet is not limited to today’s world. Paleontology, and in our case the Jurassic Mile, can give us answers about the climatic conditions of the past that can help us determine future problems that we may encounter”, Skandalos explains.

According to Van Huis, the dinosaurs themselves can also function as ambassadors for natural history museums and science in general: “Dinosaurs have enormous appeal to both young and old, a vast audience. They ensure that many families visit our museum and then explore the rest of the museum as well. Dinosaurs are also great for explaining how science works: curiosity, adventure, and research all come together here.”

Wrapping up

As the season for dinosaur digging is drawing to a close, the team is working hard to bring back the large amount of fossils they found. Extracting the bones involved carefully digging around them, consolidating them with glue, and then wrapping them in plaster jackets to protect them during their long journey to the Netherlands. “We are currently wrapping up our field season, literally and figuratively, trying to extract as many fossils as we can before we are leaving back home”, says Zethof. A daunting task after such a fruitful summer. “The bones are so plentiful, that making these plaster jackets small and manageable is a challenge.”

Van Huis is very content with the fossils that have been found so far at the Jurassic Mile. “We have already found quite a few bones of a Diplodocus and of a Camarasaurus. That is the same species as the long-necked one in our museum. Last year, we discovered several bones of an Allosaurus, the great carnivore of its time, and there is a good chance we will find many more in this area. We may discover other species in the years to come.”

Never enough dinosaurs 

Even after more than a decade of dinosaur excavations, Naturalis still has ambitious dreams. One of them, according to general director Van Huis, is to one day discover a real Stegosaurus. “The Stegosaurus we have in our dinosaur exhibit is a cast”, he says. “What would be better than finding a real one ourselves?”

But the motivation goes far beyond wish lists. Scientifically, there’s every reason to keep digging. “You can never have too many fossils when it comes to research”, says Skandalos. “The rich locality we work on in Wyoming provides us with more than enough material to use in our own research and opens the door for international collaboration between American institutions and researchers, like our colleagues from the Children’s Museum in Indianapolis. Using more specimens gives us more numbers for different statistical tests and makes the comparison and the study of the bones more efficient. So, the more the merrier!”

Back in Leiden, the work will continue. Both Zethof and Skandalos are eager to continue working on the fossils. “We are looking forward to seeing the results of this year’s excavation in the lab”, they say, “and to start planning next year’s expedition. The adventure is far from over.”

Text: Naturalis Biodiversity Center
Images: Simone Ros; Ana Soraya Marques; Esther Meijer