April 26, 2016

Paleontologist Kenneth Lacovara studies the largest creatures to ever walk this planet, the herbivorous sauropods. These dinosaurs, widespread in the southern continents during the late Mesozoic Era, towered over the Tyrannosaurus rex, standing taller than a two-story building and weighing 10 times more than a Boeing 737.

Lacovara was recently invited by Bowdoin’s Earth and Oceanographic Sciences department to give a talk on campus about his rare discovery about a decade ago of a new species of sauropod, the Dreadnoughtus schrani.

Finding a complete or near-complete skeleton of a sauropod is highly uncommon. When one would die, thudding down to the ground, they were so giant that not much of their body would actually touch the earth, where it might be preserved. Lying high above the ground, an animals’ bones would more likely be destroyed by the weather or scattered by scavengers.

Lacovara, a professor of paleontology and geology at Rowan University, in 2004 traveled to southern Argentina in search of his elusive query. After chancing upon an isolated seven-foot femur bone, he returned the next year with the modest hope of finding a few more isolated bones. However, in the first morning of the first day, he and his team unearthed one of the most intact skeletons of a never-before-discovered species of sauropod, which, along with a companion, got caught in a deluge after a natural river levy broke millions of years ago. The animals become trapped in sediment that suspended and preserved their skeletons in “exquisite detail,” Lacovara said.

“I never thought I would see a site like this in my career as a paleontologist,” Lacovara admitted. To the large crowd of students who gathered for his talk, he recounted anecdotes about his excavation, describing the arduous days, the magic and excitement of such a monumental find, the perilous drives in the steep Patagonian terrain, and some of the quirky people he worked with (one student “kind of went feral on me,” Lacovara said. “I wasn’t sure if she would re-assimilate to society.” She’s now a PhD paleontology student.).

Lacovara said that much about paleontological field work hasn’t changed in 150 years. Scientists and students simply dig, trying to find remains from a bygone world. What has changed is the technology available to paleontologists. “All the action is in the lab,” Lacovara said. Molecular paleontology, synchrotron radiation, 3D imaging, robotics, and 3D printers can help scientists better understand dinosaurs and allow them to recreate bones, muscles, and cartilage to simulate dinosaur biomechanics. “When you’re the size of a house, the penalty for falling over is death,” Lacovara said, while speaking about the tremendous stability and structure of the Dreadnoughtus. “You don’t get to fall over even once if you’re a Dreadnoughtus.”

One of the Dreadnoughtus skeletons Lacovara found was more than 70 percent complete. From it, he deduced the animal was 85-feet long from snout to tail, stood two and half stories high at its shoulder, and weighed 65 tons. And the creature was still growing when it died. “The Dreadnoughtus is the most massive land animal that we can reliably calculate a weight for,” he said.

One of the perks of being a paleontologist, Lacovara continued, is if you discover a new species you get to name it. He chose a name he thought might bestow a bit of respect on the too-often disparaged sauropod. “I always thought it was shame that these giant plant-eating dinosaurs don’t get the recognition they deserve for being very tough, scary creatures,” he said. “They’re so often portrayed as these passive, lumbering platters of meat on the landscape.” In fact, with their massive, “weaponized” tails, they’re no easy target. Lacovara decided to name his species after the dreadnoughts, a class of early 20th-century steel battleships that were impervious to pretty much all existing technology at the time.

The more he studies dinosaurs, the more Lacovara said he is in awe of them. “It’s not just their size, it’s the problems they overcame in their evolution,” he explained, adding, “These animals are hyper-efficient organisms. They could do more with a calorie of food, I think, than any animal alive today. Everything about their body speaks to these efficiencies.”

On Earth Day, Lacovara gave a TED talk, Hunting for dinosaurs showed me our place in the universe