3D Movie
Walking the Chasmosaur
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There is much that is puzzling about this enigmatic dinosaur, Vagaceratops irvinensis: What was the function of that enormous frill? How did the animal stand? How did it walk? What was its habitat like? Careful study and a little imagination are needed to find likely answers, but we will never discover all its secrets.

Including the frill, our star's skull would be 1.4 m long in real life. At its widest, the frill would be 1 m. It is likely the frill was useful for species recognition and display rituals, especially during courtship and combat (it would make the animal look larger).

This animal would be about 3 m long from the tip of its snout to its hip, with its tail adding another 2 m. The tail would have been very heavy, and would have acted as a counterbalance to the weight of the skull.

Vagaceratops irvinensis probably had a very good sense of smell; its internal nasal structure, visible in the skull and on the face in the slight depression around the nostril, is very large. Judging from the relatively small size of its eye sockets, its vision was probably not very good.

The slightly bow-legged stance of our star's front legs reflects palaeontologist Rob Holmes's belief that its weight would have been too much for a fully sprawling stance, with the 'elbows' bent outwards, like a turtle's. Few palaeontologists believe the front legs of this dinosaur would have been straight, like an elephant's.

Upon Rob's recommendation, computer animator Alex Tirabasso gave the dinosaur a pace locomotion. In this walk, the feet on one side each take their steps before the feet on the other side do. The similarity in size and mass of the dinosaur to the pace-gaited modern rhinoceros helped convince Rob that this could be how it walked.

The dinosaur is shown walking along mud plains on the shore of the now-vanished Western Interior Seaway, with the mountains we now call the Rockies visible in the distance. The fossil upon which the maquette and the identification of this species are based was found near Irvine, Alberta -- hence, the second part of its name, irvinensis.

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This image is from the Web site of the Canadian Museum of Nature. Visit the page.