Creature Feature #2

For this week's Creature Feature, we'll be looking at one of the most well-known herbivores from Hell Creek: the three-horned Triceratops.

Triceratops horridus model - model on the left is the "relaxed" texture; model on the right is the "blush" texture.

Triceratops was a large Ornithischian dinosaur in the family Ceratopsidae - its distinctive frill and three-horned face are easily recognized by both seasoned paleontologists and casual dinosaur enthusiasts. The actual function of the frill and horns has been a subject of debate for many years. The initial belief was that they served as defensive structures to protect against predators such as Tyrannosaurus rex, but more recent theories suggest that they may also have been used for display purposes. This is supported by the fact that frill shape and size as well as horn structure differ greatly between different ceratopsians, as well as the fact that modern animals with similar structures use them to intimidate rivals, attract mates, or otherwise communicate with other members of their species (Farlow and Dodson, 1975). In fact, the horns may have been used in non-fatal intraspecific combat, involving males competing for mates or simply disputes over dominance (Martin, 2006). This hypothesized function is manifested in the form of an optional "blush" mechanic. If enabled, you will be able to press a button to "blush", which causes your character to change from the "relaxed" to the "blush" texture. This can be used to intimidate rivals, attract mates, or other types of communication/signaling.

The overall anatomy of Triceratops suggests that it primarily consumed low growing vegetation, though its sheer size, along with its horn and hard beak, could have allowed it to topple larger trees in a manner similar to modern elephants (Dodson and Sampson, 2004). The deep, narrow beak at the end of their snout implies that they fed by plucking and grasping plants rather than biting as some modern grazers do (Ostrom, 1966).

Like some other herbivorous dinosaurs, Triceratops had a large number of teeth. These were arranged in groups known as 'batteries' - the number of vertical columns ranged between 36 and 40, and between 3 and 5 teeth were stacked in each column. These teeth wore down continuously, and only a fraction of the total teeth were in use at a given time (Dodson et al., 2004). The massive size and number of teeth in Triceratops suggests that it ate massive amounts of very tough plant material - suggestions range from palms and cycads (Weishampel, 1984) to ferns, which grew in prairies analogous to modern grasslands (Coe et al., 1987).

Well, I hope that gives you a little bit more knowledge about Triceratops! Tune in next week for the next Creature Feature!

Acknowledgements

Farlow, J.O. and Dodson, P. 1975. The behavioral significance of frill and horn morphology in ceratopsian dinosaurs. Evolution 29 (2): 353.
Martin, A.J. 2006. Introduction to the Study of Dinosaurs. Second Edition. Oxford, Blackwell Publishing. pg. 299-300.
Dodson, P.; Forster, C.A.; and Sampson, S.D. 2004. Ceratopsidae. In: Weishampel, D. B.; Dodson, P.; and Osmólska, H. (eds.), The Dinosauria (second edition). University of California Press, Berkeley, pp. 494–513.
Ostrom, J. H. 1966. Functional morphology and evolution of the ceratopsian dinosaurs. Evolution 20 (3): 290-308. 
Weishampel, D.B. 1984. Evolution of jaw mechanisms in ornithopod dinosaurs. Advances in Anatomy, Embryology, and Cell Biology. 87: 1-110.
Coe, M. J.; Dilcher, D. L.; Farlow, J. O.; Jarzen, D. M.; and Russell, D. A. 1987. Dinosaurs and land plants. In: Friis, E. M.; Chaloner, W. G.; and Crane, P. R. (eds.) The Origins of Angiosperms and their Biological Consequences. Cambridge University Press, pp. 225-258.