Digging Deeper into Dreadnoughtus: Dinosaur Interview Part 2

A team led by Drexel University’s Kenneth Lacovara, PhD announced a major new dinosaur discovery with a paper published in the journal Scientific Reports on Sept. 4, 2014. The dinosaur is BIG. So big that we could only fit the highlights and main points of interest into the press release – read that for a general overview of the find. Previously in Part 1 of the extended cut of our interview with Lacovara, we shared more about the dinosaur’s anatomy and lifestyle. In Part 2 below, Lacovara looks back into the process of discovery and then forward into how paleontology is going high-tech and much more.

 

Tell us more about the process of discovery. You’ve been on paleontology teams before that have discovered massive dinosaurs in China and Egypt. How do you know where to find dinosaurs, and why did you go to Patagonia in Argentina this time?

Kenneth Lacovara in a field of Dreadnoughtus ribs.
Kenneth Lacovara in a field of Dreadnoughtus ribs.

Paleontologists all use the same formula to find animals. First, whatever you’re interested in, you have to find rocks deposited in the right age. And I’m particularly interested in the dinosaurs at the end of the time of dinosaurs. So I look for rocks of the Cretaceous period. Those rocks have to be sedimentary deposits; those are the only kinds of rocks in which you can form a fossil. And then, today, not in the past, but today, it has to be an arid environment so you get good exposure of the rocks and you get good rates of erosion. It’s the erosion that cuts into the surface that exposes the bones.

So you put yourself in that situation, and then you walk. It’s the only way to find fossils. And you have to have the eye for it, you have to understand enough geology to know how to follow good deposits, and you walk until you find something that may be interesting. Now at this field site in Patagonia, virtually every pebble that you find on the ground is a piece of dinosaur bone, and in some cases, you don’t even bend over to look at the fossil. You give it a little nudge with your foot to see if it’s in place, or anything interesting, and nine times out of ten it’s just a fragment which isn’t scientifically useful. But every now and then you find a complete bone. And every now and then that bone is connected to another bone, and in this case it was connected to 234 other bone elements, and we ended up spending about a year total at that site in the field excavating this dinosaur.

Patagonia is known for its dinosaur richness. However, almost all the species have come from northern and central Patagonia. So I went to the end of South America, the end of Patagonia, as they say Fin del Mundo, the end of the Earth. There I had an area about the size of the state of Connecticut, which has three houses in it, and this vast region for prospecting [fossils from] the Late Cretaceous period. It’s kind of a paleontological wonderland. When you drive there you see these deposits that dwarf the kinds of things that you see in Montana and Wyoming, and it just staggers the imagination to think about how many fossils are actually in the ground there.

It staggers the mind to see the kind of fossils you actually found there! How long did it take you to discover Dreadnoughtus?

Our first field season down there was in 2004, and that was a rough field season. We didn’t have a road to access the area, so we had to raft down a glacial stream to get to the site. We were about a hundred miles off the power grid, and couldn’t carry many supplies out there, so our rations were meager. We began to find remains of giant dinosaur bones, but they were all fragmentary, and they were, for the most part, preserved with iron minerals. And most of the fragments we found that year were at the top of a mountain. I attempted to get a helicopter from the Argentinian Air Force to extract these bones, and they actually said yes, but the deal fell through at the eleventh hour. So I had to find and hire two teams of gauchos with their horses, and we built metal sleds and wooden toboggans to extract that material.

The first field season anywhere there’s a lot of pressure to make some discovery in order to justify the project and return trips. We found enough material that first year to justify a return trip.

Stormy skies over the remote and weatherbeaten Dreadnoughtus quarry
Stormy skies over the remote and weatherbeaten Dreadnoughtus quarry

On the first day of the 2005 expedition, while prospecting for fossils, I spotted a small patch of bones and recorded the location with his GPS. We returned a few hours later and began excavating. By the end of the day, we had exposed about ten bones of what we would eventually call Dreadnoughtus schrani. Four expeditions later, we had collected 145 bones of this new giant dinosaur.

Was there any risk someone else could have discovered the dinosaur when you left it unattended for half a year between field seasons?

Not really. The site is protected by its remoteness. Also, you have to be really motivated and well equipped to dig up a sauropod.

Who went with you to dig up the Dreadnoughtus fossils?

Initially when I went down to Patagonia I went with myself, some volunteers from the University of Patagonia; I had some technicians from the laboratory at the University of Patagonia, which is about a thousand miles away from the field site. When I went back the next year, I took a Drexel graduate student and that turned out to be a great experience.

The year after that, I took more graduate students, and for the first time a Drexel undergraduate, Alison Moyer, who was a sophomore biology major at the time. I had great trepidation about bringing an undergraduate to such a remote field site. We got down there, and Alison informed me then that she had never been camping before, which was probably a question I should have asked earlier. She did great that field season, so much so that I brought her back the next year. She became a leader among the team. In fact, at one point, she had kind of gone feral on me, and I worried about whether she would re-assimilate into ‘polite Philadelphia society’ when we got home. Now she has graduated and she’s at North Carolina State University working on her PhD in molecular paleontology, and she will be in the vanguard of the first fully trained researchers in this new field of science, so I’m very proud of her.

You brought Drexel students to Argentina, and also Argentinian students to Drexel, right?

Another very satisfying aspect of this project is I was able to take two Patagonian undergraduate students who volunteered on my project and bring them up to Drexel University to work on their doctorate degrees. Lucio Ibiricu finished his PhD in paleontology three years ago with me, and his girlfriend, initially, and now his wife, Gabriela Blanco, finished her PhD at Drexel in marine biology. They are both now back in Argentina, employed by the Argentinian CONICET , which is like their National Science Foundation. And so now we have a new generation of Patagonian-born scientists that are taking the lead in science in their country.

Left to right: Jason Poole, Christopher Coughenour, Alison Moyer, Kenneth Lacovara, Lucio Ibiricu, Jason Schein, Yanko Kamerbeek
Dreadnoughtus excavation team in Patagonia. Bottom row, left to right: Lucio Ibiricu, Victoria Egerton. Top row, left to right: Jason Schein, Jason Poole, Jessica Battisto, Kenneth Lacovara, Alison Moyer.

What is the process of digging up bones this big and bringing them home for study?

When you find a bone in the field, you begin to excavate the rock around that bone. It’s very difficult in this site because the rock is like concrete, so we’re using hammers and chisels and pickaxes all day, but you try to leave some rock on the bone because the rock has stabilized that bone for millions and millions of years. You want it to continue to do that while you transport the bone. And so we leave a veneer of rock around the bone, and we chop down until we pedestal a bone. And then we begin to tunnel underneath of it, and we wrap bandages of burlap and plaster around the bone. For big bones like the femur, we’ll jacket some steel bars into it. Then eventually we have it encased in this plaster cocoon that protects it during transport.

A single cervical (neck) vertebra from Dreadnoughtus, being jacketed by former Drexel students Jessica Battisto (left) and Alison Moyer (right)
A single cervical (neck) vertebra from Dreadnoughtus, being jacketed by former Drexel students Jessica Battisto (left) and Alison Moyer (right)

When we get it here, we have to open those jackets much like a physician would open up the cast on a broken arm. And then we have to very careful remove the rock that is attached to the bone. Sometimes we can do that with dental tools. Sometimes we have to use these mini jackhammers called airscribes. It’s very painstaking work. The bones expand when you take the rock off them, and so you get expansion cracks that form. We use [specialized adhesives for paleontology] to stabilize those cracks, to infill those cracks, and to make the fossil stable so that it will last for centuries in a museum.

All the products that we use are easily reversible with acetone so that if a paleontologist two hundred years from now doesn’t like how we did the work, they can reverse it and do it again in the way that they see is best. We also try to make the work very transparent to future paleontologists. We don’t camouflage the putty or try to paint the putty to match the bones. We want them to know what’s the original material and what is the work that we’ve done.

Tell us about the ownership of the bones and how you were able to bring them to Philadelphia temporarily.

Most countries in the world have laws that govern their fossil resources. In Argentina, it doesn’t matter where a fossil is, it doesn’t matter who finds it. When you break the surface on that fossil, it immediately becomes property of the federal government of Argentina, which is fine, and that’s how it should be. So I was able over a long period of negotiation to arrange an exportation of the fossils for research to Drexel University over a four-year period. [The initial loan period was extended in 2013.] So this has resulted in a lot of great collaboration and cooperation with scientists in Argentina, with the national museum in Argentina, the provincial museum in Santa Cruz province… Soon we will be crating all these bones and sending them back to their home in southern Patagonia.

What techniques are you using to study this dinosaur?

Dinosaur paleontology is about 150 years old. And in all that time, paleontologists have only had the shapes of the bones to go on, in terms of interpreting the biology of these creatures. And so the more bones for a particular individual, the more we know about its biology, the more we know about its physiology. A dinosaur in this mass range, 65 tons, is pushing the limit as to what is physiologically possible. So it would be very hard to understand this dinosaur from a very fragmentary skeleton. We’re fortunate that we have nearly a complete skeleton of this amazing creature, so we’re going to be able to understand kind of the frontier of physiology, in terms of supermassive land animals, from this animal.

But technology in paleontology is also changing. What more are you doing now in addition to examining the shape of the bones to learn about this dinosaur? Where is paleontology headed in the future?

So for about 150 years the technology in paleontology has changed little, and it’s consisted largely of shovels and hammers and pickaxes and chisels and burlap and plaster. And in the field I do things much the same way my predecessors do. I use horses sometimes and sleds and whatever I can do to move heavy objects in the wilderness.

Lacovara’s team prepared 3D laser scans of most of the fossil bones from Dreadnoughtus schrani, making them available to other researchers – or to anyone – for future study. Here, Lacovara works with doctoral candidate Anna Jaworski scanning the Dreadnoughtus femur.
Lacovara’s team prepared 3D laser scans of most of the fossil bones from Dreadnoughtus schrani, making them available to other researchers – or to anyone – for future study. Here, Lacovara works with doctoral candidate Anna Jaworski scanning the Dreadnoughtus femur.

Back in the lab here, though, we’re starting to apply some very cutting-edge techniques to studying this dinosaur. We’re still doing the traditional study of the shapes of the bones, the morphology of the bones. But we’re doing two things that are quite new.

One is that we’re using a 3D laser scanner to capture the digital form of these bones and then essentially we can digitally curate the fossil. This has the advantage that it doesn’t take space. These images can be ported around the world to other scientists, other museums. The fidelity is perfect. It doesn’t decay over time like some bones do in a collection. And we can use them in biomechanical models, both virtual ones, and we’re starting to use 3D printers to actually print out one-tenth scale copies of these bones. We could print out one-to-one scale copies so we could use the printed bones to make robotic analogs of these dinosaurs, and we could use these robots to test our biomechanical hypotheses. The advantage that a robot has over a virtual simulation is that robots exist in the world. So if you don’t have the processing power to include certain variables, or if you don’t think to include certain variables, it doesn’t matter, because they’re in the world, and the same variables that are affecting you are affecting these dinosaur robots.

The one thing we can assume about these supermassive giants is that they’re extremely efficient with every calorie that they take in. You can’t get that big otherwise. So as we develop these robotic models, we can measure the energy going in, we can measure the energy consumed, and then we can tweak the model to try to find a more efficient form. And the closer we get to the most efficient form, I think, the closer we get to the truth of how these animals existed.

The other cutting-edge technology that we’re using to study this animal falls in the realm of a new science that’s called molecular paleontology. Now if you buy a geology textbook today, it will tell you that in fossilization, an animal is buried, the animal becomes a mineral copy of its former self, and all the tissue and all the soft parts decay away, and you’re left essentially with a stone that looks like the animal. We know now that that’s not the complete truth. And so what we’re doing in this lab is we’re taking portions of bone, demineralizing that bone, and what we’re finding is there’s a residue behind that consists of cells and soft tissue that is, in this case, 77 million years old, and actually from this dinosaur. And we can verify that in different ways.

Eventually, the dream for molecular paleontology, is essentially what we’re looking at is bar codes on fossils. Many of the fossils that paleontologists find, the vast, vast majority, are just fragmentary bones that are not identifiable. And so eventually we may be able to take the random fragment that we find on the ground, recover ancient biomolecules, sequence those molecules and identify what dinosaur it was, which will vastly increase our knowledge of biodiversity in the ancient world, and will eventually help us understand the physiology, evolution and lifestyles of these animals. So we’re entering a period where, rather than studying these stony relics from the past, paleontologists are going to be able to study ancient creatures in the same way that a biologist today can study a salmon or a raccoon.

Note to news media: Additional resources, including available multimedia resources and other information about Dreadnoughtus schrani are available from the Dreadnoughtus resource page at https://newsblog.drexel.edu/dinosaur.

For news media interview requests for Kenneth Lacovara, contact Rachel Ewing, raewing@drexel.edu, 215.895.2614.