Nicholas Judson - Triceratops, 2007

Triceratops, 2007

Pencil on paper drawing. 5" x 7". Dinosaur displayed at the National Museum of Natural History, Washington, DC.

Greeting card reproductions of this image are available for purchase.

Triceratops horridus. Triceratops were herbivores that reached about 10 feet tall and are estimated to have weighed between 6.5 and 13 tons. They roamed what is now western North America in the Late Cretaceous, 70 to 65 million years ago. The first Triceratops skeleton was discovered in Colorado in 1887; while many specimens have been found, which has allowed the assembling of composite animals, to date a complete skeleton has not been recovered. This has made it difficult to reconstruct one where the relative sizes of all bones are in proportion.

Triceratops has inspired several hypotheses, although these are hard to prove or disprove. It is commonly thought that Triceratops, like modern rhinoceroses, exhibited herding behavior; however, there is no evidence for this, as all skeletons found have been solitary. It has also been hypothesized that a likely predator for Triceratops was Tyrannosaurus rex. While a lone Triceratops pelvis has been found with healed tooth marks from T. rex, there are no other direct examples.

The skull from the specimen drawn here was collected in 1890 in Wyoming. While a reconstructed skeleton made of fossil bones from several individual sites was first exhibited in 1905, a more accurate version -- both in terms of its proportionality and its stance -- has been produced by scanning the bones of that composite skeleton and constructing a digital representation. This 3D digital model has allowed casts of all bones to be produced that are correctly proportioned relative to each other.

This drawing is of a cast of this skeleton which was first displayed in 2001, at the Smithsonian Institution National Museum of Natural History, in Washington, DC.