When Kenneth Lacovara spotted bones poking out of the soil in the Patagonian Desert in 2005, he didn't think much of it. Then he began to dig. Lacovara and his team had stumbled across a two-metre-long femur, the leg bone of one of the largest land dinosaurs ever discovered. The findings marked the beginning of a four-year excavation, which unearthed 145 bones from a 26-metre-long skeleton. Lacovara christened the dinosaur Dreadnoughtus schrani, which means "fears nothing". "It's mind-boggling to lie in the desert next to a femur that's two metres long and imagine the creature that was attached," says the 55-year-old.
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A palaeontologist based at Rowan University in New Jersey, Lacovara studies the Cretaceous Period and its dinosaurs - preferably the largest ones. "My wife says when I'm looking for my keys in the morning that I study big dinosaurs because I can't find anything smaller," he jokes. Case in point: the Dreadnoughtus, a 65-tonne herbivorous titanosaur, which probably roamed South America about 77 million years ago. "It's as heavy as a Boeing 737. It's staggering to imagine that these things were real. I've never quite got over that."
Lacovara's search for the planet's largest creatures has taken him on digs in Patagonia, Mongolia and North Africa. He's known for his discovery of Paralititan, another huge titanosaur, in Egypt, and Suzhusauraus, a clawed creature with wing-like arms, in the Gobi Desert. But Dreadnoughtus remains his most celebrated discovery. "A 65-tonne Dreadnoughtus defending its territory in breeding season would have been a ridiculously hazardous animal to be around. It harked back to the dreadnoughts [20th-century British warships] so I gave it that name." At his lab at Rowan, Lacovara is using 3D modelling and repurposed medical technologies to reveal how this ancient behemoth lumbered across Earth.
Lacovara relies on the exquisite preservation of Dreadnoughtus's bones. They show the scars of their muscle attachments in detail, which allows him to map these points on the virtual models used to make 3D prints of the bones. Using biomechanical modelling, Lacovara runs virtual experiments to examine the efficiency of these artificial limbs. He also uses robotics to mimic their motion. The models are driven by algorithm-powered motors to reveal the power required to propel the dinosaur's limbs, as well as details about the cartilage between Dreadnoughtus's joints. "The more efficient the motion becomes, the closer we get to the truth of these animals. Because if you're 65 tonnes, you have to be efficient with every calorie you take in," Lacovara says.
His lab is also investigating the makeup of the bones and applying medical techniques to identify molecular traces of blood and tissue. For years, researchers believed fossils were mineralised bone. In fact, they carry organic remnants too, Lacovara says. Pioneering research by palaeontologist Mary Schweitzer at North Carolina State University relies on antibodies usually applied to birds to detect organic traces in bone. Because birds are close descendants of dinosaurs, antibodies that would ordinarily bind to their proteins can recognise ancient proteins too.
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With sequencing, hereditary information contained in those proteins can be deciphered, which may help palaeontologists situate a specimen in the family tree, and even identify a species. "What we're looking at is barcodes on fossils," Lacovara says. "I see this technology as being portable someday. A scrap of dinosaur bone would be useless to palaeontologists today, but in the future, we could sequence those proteins and say, 'Oh, I didn't know the Triceratops was in Europe. Isn't that interesting?'" Every dinosaur specimen in Lacovara's lab is 3D laser-scanned, allowing researchers to share findings. "To my knowledge, Dreadnoughtus was the first new dinosaur species published [online] along with its 3D images," he says.
Lacovara's emphasis on accessible science is embodied in the Edelman Fossil Park, which he runs at Rowan University. The 26-hectare plot rests in an old quarry in New Jersey and contains a rich deposit of fossils from the Cretaceous period. The park is run as an educational dig site, where students can take guided tours with Lacovara to look for fossils. But for palaeontologists, it's also an important research plot: the quarry contains a bone bed stacked with ancient skeletons of sharks, rays, crocodiles and fish. Other creatures are puzzlingly whole - not something you'd expect if they'd been deposited by the sea or a mudslide. All these signs point to a mass die-off, which Lacovara believes may have been caused by an asteroid that landed off the Gulf of Mexico 66 million years ago.
If Lacovara can prove this to be case, Edelman Fossil Park will be the only place for visitors to view creatures killed on that calamitous day. This year, he hopes to have an answer to his theory, which could reveal unknown details about dinosaurs' demise. Despite palaeontologists' obsession with the past, it's the future they're concerned about. "If we want to understand how the biosphere responds to climate change, that data is in the past. Without that, we're flying blind into our environmental future."
This article was originally published by WIRED UK
