Protoceratops: Beast of the Week

This week we will be looking at a well known ceratopsian dinosaur.  Say hello to Protoceratops!  This little dinosaur measured about six feet long when fully grown and lived in what is now Monglolia during the Late Cretaceous, roughly 80 to 75 million years ago.  Like all ceratopsians, Protoceratops was likely a plant-eater.  The genus name, Protoceratops, literally translates to "first horned face".  Nowadays we know that Protoceratops was far from the earliest of the ceratopsians but at the time of its discovery back in the 1920s it was the oldest known.  The discovery of Protoceratops also proved to scientists that the ceratopsian family line originated in Asia, not North America, where its later-living relative, Triceratops, was unearthed.

Life reconstruction of two Protoceratops by Christopher DiPiazza.  There are variations in the skull shapes among the many Protoceratops on the fossil record.

Protoceratops, like many of its relatives had a broad frill growing from the back of its skull, made lighter by two large holes, called finestra.  It had a hooked beak, which would have been backed up by extremely powerful jaw muscles, which enabled this dinosaur to eat the tough, and possible thorny vegetation that lived in its arid habitat.  It had proportionally long legs for a ceratopsian, and its tail that was flattened laterally by elongated neural arches.

Protoceratops skeletons on display at the American Museum of Natural History in New York.

Protoceratops is a great dinosaur to study because there are just so many specimens on the fossil record.  Scientists have found tiny babies, fully grown adults, and many life stages in between.  There is even a three-dimensional articulated skeleton on display at the Museum of Natural History in New York.  Because there are so many individuals of Protoceratops on the fossil record, scientists were noticed that even among adult-sized animals, there was variation in their skull shapes.  Some individuals had wide, frills and extremely tall snouts, while others had more narrow snouts and proportionally smaller frills.  Some have suggested this is an example of sexual dimorphism, the larger-headed individuals being males, and the more narrow-headed ones, the females.  Others have countered that this also may be simply a difference in maturity even after the animal's overall body size has reached adulthood.

Protoceratops skulls on display at the American Museum of Natural History, showing small babies leading up to mature adults.

Protoceratops was likely a tough little dinosaur.  It had to be since its habitat would have been an arid desert.  Protoceratops' small size in this environment is no coincidence since desert animals tend to evolve smaller.  The smaller your body is, the less food and water you require to stay alive, and the easier it is to get shelter.

An often overlooked, but impressive specimen of a Protoceratops preserved in the pose it died in, likely due to a sandstorm, io display at the American Museum of Natural History in New York.

A crushed Oviraptor skull was discovered nearby what were originally believed to be Protoceratops eggs.  Scientists thought that the ceratopsian defended its brood by pulverizing the poor theropod's head.  As it turns out, the eggs actually belonged to Oviraptor, not Protoceratops.  Since that discovery, however, paleontologists have found young Protoceratops in nests of their own, as well.  This suggests that Protoceratops, like many other dinosaurs, cared for its young for a time after they hatched. 

Famous fossil that shows what appears to be a Protoceratops and Velociraptor fighting.

An even more spectacular fossil was found during the early 70s of a Protoceratops with a Velociraptor's arm clamped in its beak.  It appears that the Velociraptor's toe claw was embedded in the ceratopsian's neck and that the two were locked in dramatic mortal combat when they perished in a sandstorm.  Whether or not this is actually how they died is truly uncertain.  One thing that is for sure, however, is that these two dinosaurs were practically on top of each other when they died and I'm pretty confident it wasn't to cuddle.  One of the reasons why I love Protoceratops so much is because despite it having been a plant-eater (and a relatively small one at that), it actually proves to have probably been a force to be respected by other dinosaurs when it was alive.  Plant-eaters always get this "gentle" label which is just plain false.  Just take a look at animals today like Buffalo and Hippos, which can be extremely aggressive, to see what I mean.  Extinct dinosaurs, like little Protoceratops, could have been much the same.

 That is all for this week!  As always feel free to comment below or on our facebook page!

References

Carpenter, Ken. (1998). "Evidence of predatory behavior by theropod dinosaurs.". Gaia 15: 135–144. [not printed until 2000]

Choi, Charles. "15 Infant Dinosaurs Discovered Crowded in Nest". LiveScience.com. November 17, 2011.

Maiorino, Leonardo, et al. “Males Resemble Females: Re-Evaluating Sexual Dimorphism in Protoceratops Andrewsi (Neoceratopsia, Protoceratopsidae).” Plos One, vol. 10, no. 5, 2015, doi:10.1371/journal.pone.0126464.

"Protoceratops." In: Dodson, Peter & Britt, Brooks & Carpenter, Kenneth & Forster, Catherine A. & Gillette, David D. & Norell, Mark A. & Olshevsky, George & Parrish, J. Michael & Weishampel, David B. The Age of Dinosaurs. Publications International, LTD. p. 118-119. ISBN 0-7853-0443-6.

Dodson, P. (1996). The Horned Dinosaurs. Princeton University Press, Princeton, New Jersey. pp. 200–234. ISBN 0-691-05900-4.

 Mayor, A. (2000). The First Fossil Hunters: Paleontology in Greek and Roman Times. Princeton University Press, Princeton, New Jersey. ISBN 0-691-05863-6.