7-year-old fossil fan helped discover dinosaur
With help from a fossil-loving schoolboy, scientists have unveiled a bizarre mishmash of a dinosaur that was a distant cousin of uber-predator Tyrannosaurus rex – but also a committed vegetarian.
Eleven years ago, Diego Suarez was 7 and on a research expedition with his geologist parents when he spotted the first bones of the species, which lived 145 million years ago. It was named Chilesaurus diegosuarezi in his honor. Diego's dinosaur had many features in common with carnivorous dinosaurs, but it did not conform to type. Its small head and leaf-shaped teeth were like those of a plant eater, researchers report in this week's Nature.
"It's like a T. rex that's been shrunk but not shrunk equally," says Pete Makovicky, an associate curator and dinosaur specialist at The Field Museum in Chicago, who was not involved in the new find. "This animal would've looked more silly than fearful … more similar to an ostrich than to T. rex."
The species has "really thrown me for a loop," says paleontologist Steve Brusatte at the University of Edinburgh via email. "There is nothing else that's been found before that looks remotely like this."
Chilesaurus is a remarkable example of beginner's luck. In 2004, Diego accompanied his parents on a field trip in southern Chile. At a Jurassic rock site, he recalls, he borrowed his mother's pickax and began digging at the ground.
"Out of nowhere, two small things appeared. … They were fossils," Suarez says by email. He ran to show his mother. His parents, he says, "were amazed. You (can) imagine it was, to them, like wining the lottery." The family sent the fossils to dinosaur specialists in Argentina.
At first the disconnected bones found by Diego and his family were thought to belong to several different species. But when Fernando Novas, an author of the study reporting the new species, returned to the site, he found intact skeletons like nothing he'd ever seen before.
The scientists went back to the site four more times over several years to excavate the complete discovery.
"This new animal combined features belonging to three different lineages" of dinosaurs, says Novas, a paleontologist at Argentina's Bernardino Rivadavia Museum of Natural Sciences. "It was so shocking."
It had vertebrae like those of the family that includes predators T. rex and Velociraptor, but its feet, ankle and some of its pelvis looked like they belonged to a completely different branch of plant-eating animals. Study co-author Martin Ezcurra of Britain's University of Birmingham calls it the "platypus dinosaur" after the Australian mammal with a beak like a duck's.
Chilesaurus's ancestors were meat eaters, but somewhere along the way it turned to a diet of plants. In the process, it traded sharp teeth and a runner's body for joints more suited for walking and a spacious gut for digesting big wads of plant material.
Most of the Chilesaurus fossils found at the site are the size of chickens or turkeys, but the biggest would have been 10 feet long, Novas says. He thinks the site might have been a Chilesaurus nesting ground, which would explain the concentration of miniature animals. The site also contains crocodile-like creatures and larger plant-eating dinosaurs, all discovered thanks to a kid with a passion for bones.
"It's amazing to have found this new species," says Suarez, now an 18-year-old university student. "I feel this incredible joy from being able to be part of something big."