Small, Speedy Plant-Eater Extends Knowledge of Dinosaur Ecosystems

May 22, 2013 — Dinosaurs are often thought of as large, fierce animals, but new research highlights a previously overlooked diversity of small dinosaurs. In the Journal of Vertebrate Paleontology, a team of paleontologists from the University of Toronto, Royal Ontario Museum, Cleveland Museum of Natural History and University of Calgary have described a new dinosaur, the smallest plant-eating dinosaur species known from Canada. Albertadromeus syntarsus was identified from a partial hind leg, and other skeletal elements, that indicate it was a speedy runner. Approximately 1.6 m (5 ft) long, it weighed about 16 kg (30 lbs), comparable to a large turkey.

Albertadromeus lived in what is now southern Alberta in the Late Cretaceous, about 77 million years ago. Albertadromeus syntarsus means "Alberta runner with fused foot bones." Unlike its much larger ornithopod cousins, the duckbilled dinosaurs, its two fused lower leg bones would have made it a fast, agile two-legged runner. This animal is the smallest known plant-eating dinosaur in its ecosystem, and researchers hypothesize that it used its speed to avoid predation by the many species of meat-eating dinosaurs that lived at the same time.

Albertadromeus was discovered in 2009 by study co-author David Evans of the Royal Ontario Museum as part an on-going collaboration with Michael Ryan of the Cleveland Museum of Natural History to investigate the evolution of dinosaurs in the Late Cretaceous of North America. The known dinosaur diversity of this time period is dominated by large bodied plant-eating dinosaurs.

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