Turkey-sized dino outran predators
Albertadromeus a fast, two-legged racer: researchers
CALGARY — They were the size of a large turkey, but the speedy plant-eaters still managed to survive alongside the fierce, meat-eating dinosaurs in southern Alberta about 77 million years ago.
The discovery, published this week in the Journal of Vertebrate Paleontology, was made in 2009 by a team of researchers from the University of Toronto, Royal Ontario Museum, Cleveland Museum of Natural History and the University of Calgary.
It’s called Albertadromeus syntarsus, which means “Alberta runner with fused foot bones.”
The new dinosaur, identified by a fossilized partial hind leg and other skeletal elements, fills an important gap in the knowledge about dinosaur ecosystems.
“It shows us that dinosaur communities were structured much in the way that mammal communities are structured today,” Anthony Russell, a professor of biological sciences at the U of C, said in an email interview from southern Africa. “The smaller animals are much less well known to people in general than are the larger, more conspicuous ones — if one goes to Banff (National) Park, for example, most people are looking to see bears, mountain lions and elk, and have less chance seeing martens, pikas, wood rats and the like.
“The absolute size of the animals is different … but the principles and the economics are the same.”
The specimen found in southern Alberta is the smallest known plant-eating dinosaur in its ecosystem, measuring 1.6 metres long and weighing 16 kilograms.
Its fused lower leg bones would have made it a fast two-legged runner — likely allowing it to avoid predation by big, meat-eating dinosaurs.
The animal was discovered as part of ongoing research into the evolution of dinosaurs during the Late Cretaceous period, when the known dinosaur diversity is dominated by larger, plant-eating dinosaurs.
Caleb Brown, who’s finishing his PhD in the department of ecology and evolutionary biology at the University of Toronto, said the most important specimen was found by his supervisor, David Evans of the Royal Ontario Museum, in the Milk River valley in southern Alberta.
Others have been found in Dinosaur Provincial Park, near Brooks, by researchers with the Royal Tyrrell Museum in Drumheller.
“They were more diverse and more abundant than we had thought,” said Brown, noting smaller animals can be overlooked because they are less likely to be preserved than larger ones — because their bones are more delicate and often destroyed before being fossilized.
Brown said it provides important perspective to those who have been studying the period.
“It’s one more piece of the puzzle in terms of the environment these animals lived in,” he said.
“It’s another in a series of papers that clarified what their environment was and what their food chain looked like.
“This animal would have been near the bottom of the food chain.”