A previously unknown, very tiny dinosaur has been discovered. The tyrannosauroid, named Suskityrannus hazelae, stood roughly 3 feet tall at the hip and was about 9 feet in length—only slightly longer than the skull of its full-grown cousin, the famed Tyrannosaurus rex.
S. hazelae weighed between 45 and 90 pounds, with a diet likely made up of smaller animals. The fossilized remains of a 3-year-old dino, dated 92 million years to the Cretaceous Period, speaks to the evolution of tyrannosauroids.
“Suskityrannus gives us a glimpse into the evolution of tyrannosaurs just before they take over the planet,” says Sterling Nesbitt, an assistant professor with Department of Geosciences in the Virginia Tech College of Science, in a press statement. “It also belongs to a dinosaurian fauna that just proceeds the iconic dinosaurian faunas in the latest Cretaceous that include some of the most famous dinosaurs, such as the Triceratops, predators like Tyrannosaurus rex, and duckbill dinosaurs like Edmotosaurus.”
It’s been a long journey for S. hazlae. In 1997, Robert Denton led an expedition in the Zuni Basin of western New Mexico and first discovered traces of the dino. A year later, Nesbitt found a more complete specimen in the same area. But here’s the remarkable part: While Denton was a professional archaeologist, Nesbitt was merely a high-school junior at the time.
Back then, the aspiring palaeontologist took part in an expedition with Zumi Paleontological Project leader Doug Wolfe and James Kirkland, now of the Utah Geological Survey.
But at the time, scientists didn’t know as much as they do now about predators related to the T. rex. In fact, they thought S. hazlae might have been a small Velociraptor. The bones sat in Nesbitt’s hometown Arizona Museum of Natural History in Mesa from 1998 until 2006.
“I was always hesitant to say I found something new,” Nesbitt tells The Roanoke Times, speaking about his early discovery. “I was being a careful scientist.”
Discoveries in China of the Dilong paradoxus, another small tyrannosaur, provided a more complete understanding of the tyrannosauroid dinosaur family, making today’s scientists feel confident about their decision. They now believe S. hazlae, one of the last small dinosaurs, played a big role in species evolution.
“Suskityrannus is a key link between the enormous bone-crunching dinosaurs like T. rex and the smaller species they evolved from,” Steve Brusatte, a palaeontologist at the University of Edinburgh, says in a statement to LiveScience.
“The new species shows that tyrannosaurs developed many of their signature features like a muscular skull, broad mouth, and a shock-absorbing foot when they were still small, maybe as adaptations for living in the shadows,” says Brusatte, who was not involved in the study.
More than 20 years later, the magnitude of Nesbitt’s finding isn’t lost on him.
“My discovery of a partial skeleton of Suskityrannus put me onto a scientific journey that has framed my career,” Nesbitt says. “I am now an assistant professor that gets to teach about Earth history.”
Source: Virginia Tech
Originally published on Popular Mechanics