Although such horns are common features of ceratopsid dinosaurs, those of Coahuilaceratops appear to be the largest known for the group, exceeding the size of eye horns even in Triceratops. Scientists are uncertain of the massive eye horns' purpose, but the most widely accepted idea is that they were related to reproductive success, functioning to attract mates and fight with rivals of the same species.
Loewen explained that Coahuilaceratops represents the first occurrence of an identifiable species of horned dinosaur in southern Mexico. "The horned dinosaurs are an extraordinary example of vertebrate evolution," he said. They evolved and diversified on Laramidia along a thin strip of land that stretched from Alaska to Mexico. "Finding this horned dinosaur so far south in Mexico offers us a different picture of what the ancestors of Triceratops were like."
An Ancient Ecosystem Revealed
In addition to Coahuilaceratops, the research team found remains of two other horned dinosaurs, which are less well understood. "We need more material to figure out what these other horned dinosaurs looked like," Getty said.
The latest expedition also recovered remains of two duck-bill dinosaurs, as well as the remains of carnivores, including large tyrannosaurs (smaller, older relatives of T. rex) and more diminutive Velociraptor-like predators armed with sickle-claws on their feet.
Together with an abundance of fossilized bones, researchers discovered the largest assemblage of dinosaur trackways known from Mexico, an extensive area crisscrossed with the tracks of different kinds of dinosaurs. In all, the emerging picture shows a diverse group of dinosauria
|Contact: Patti Carpenter|
University of Utah