Sunday, June 29, 2014

Mercuriceratops: Prehistoric Animal of the Week

Today we will be looking at another exciting, newly-discovered dinosaur with a beautifully unique frill!  Enter Mercuriceratops gemini!  Only formally described this year, Mercuriceratops was a plant-eating dinosaur that lived in what is now Alberta, Canada and Montana, USA. it lived during the late Cretaceous period, 77 million years ago and measured about twenty feet long from beak to tail. It's genus name, Mercuriceratops, translates to "Mercury Horned Face".  This is in reference to the Roman messenger god, Mercury, who was able to fly thanks to the wings on his helmet.  Mercuriceratops also had "wings" or rather extra wing-shaped structures on the sides of its bony frill.  What an appropriate name!  The species name, gemini, was given because Mercuriceratops is known from two nearly identical specimens, one from Montana, and the other from Alberta.  Each fossil, although from different individual animals that died in different places, are from the exact same parts of each specimen's frill!  Maybe they called each other the night before and arranged it that way?

Life reconstruction of Mercuriceratops gemini by Christopher DiPiazza.

 Mercuriceratops belongs to the subfamily of ceratopsid dinosaurs (beaks, horns, and frills) called chasmosaurinae.  These members of the ceratopsid family are characterized by their longer frills and normally narrower snouts.  Other examples of chasmosaurine ceratopsids are Chasmosaurus, Coahuilaceratops, Vagaceratops, and TriceratopsMercuriceratops' fossils are the oldest of any chasmisaurine to ever be discovered in Canada.

Image of the fossils from Montana and Alberta which would have been parts of Mercuriceratops' frill from the paper by Michael Evans, formally describing the new species.

There are a lot of unique horn styles amongst ceratopsids that  have been discovered over the years but Mercuriceratops is the only one known to have a frill that was this unique.  During the late Cretaceous (specifically the Campanian age, spanning from about 83 to 72 million years ago) there have been dozens of amazing ceratopsids discovered which tells us that whatever the environment was like back then, it definitely favored the horned dinosaurs and prompted an explosion of biodiversity amongst them.  Each species would have used a unique horn/frill shape (and probably colors too) to attract mates and communicate with each other within the species.  We can see similar biodiversity in Africa, with all the different kinds of gazelles and their differently-shaped horns.  If you want a closer related modern example, just check out all the different kinds of related birds in any given ecosystem and how they all showcase different coloration and songs for the same evolutionary reasons.  Sadly, so far only parts of Mercuriceratops' frill have been discovered and the exact shape of its horns is still a mystery. 

That is all for this week!  Feel free to comment below or on our facebook page!  When you hear from me next week I will be posting from New Mexico, doing fieldwork, excavating Triassic fossils! 

Works Cited

Ryan, M. J.; Evans, D. C.; Currie, P. J.; Loewen, M. A. (2014). "A new chasmosaurine from northern Laramidia expands frill disparity in ceratopsid dinosaurs". Naturwissenschaften. doi:10.1007/s00114-014-1183-1.

Sunday, June 22, 2014

Corythosaurus: Prehistoric Animal of the Week

This week we will take a look at a well known duckbill dinosaur.  Enter Corythosaurus casuariusCorythosaurus was a plant eater that belonged to the lambiosaurine group within the family, Hadrosauridae. (duckbills)  Lambiosaurine hadrosaurs typically had hollow crests on their heads and narrower beaks compared to other kinds hadrosaurs.  It was closely related to other lambiosaurine hadrosaurs such as Parasaurolophus, Tsintaosaurus, and Velafrons.  It lived in what is now Alberta, Canada, during the Late Cretaceous, about 75 million years ago.  Corythosaurus could have measured up to thirty feet long from beak to tail and its genus name translates to "helmet lizard/reptile" because of its helmet-shaped crest.  When alive, it would have coexisted with many other dinosaurs, including Chasmosaurus, Styracosaurus, Struthiomimus, and its relative, Parasaurolophus, just to name a handful. 

Corythosaurus casuarius life reconstruction, representing two males and a female.

The crest of Corythosaurus, despite the name, wasn't really a helmet.  (Although another group of dinosaurs, the pachycephalosaurs, did have skulls that served a purpose similar to that of helmets.)  Its crest was circular-shaped, and hollow on the inside, housing a network of tubes that connected the animal's nostrils to its windpipe.  Originally scientists thought this was an adaptation for a semi-aquatic lifestyle, but they were most likely for amplifying the sounds that Corythosaurus made.  Corythosaurus could inhale through its nostrils, where the air would pass through the series of tubes before being released through the mouth, thus producing a louder sound, than if the tubes weren't present, much like the inner workings of trumpets or other brass wind instruments.  Sound was probably a very important method of communication for Corythosaurus and its relatives.  In fact, thanks to a beautifully preserved specimen of Corythosaurus, paleontologists were able to discover highly developed inner ear bone, further supporting this idea.  The Corythosaurus genus used to consist of several species with similar crests of varying sizes.  It was later realized, however, that these specimens were more likely different ages and sexes of the same species since they were all found in the same area together and the largest specimens had the largest crests.  Since male and female Corythosaurus likely had different looking crests, they also probably had different sounding calls.  We can see this today with their modern relatives, the birds and crocodilians, as well as other kinds of animals like frogs and insects.  In the case of some of these animals the males are the only ones that call at all!  That lovely chorus of crickets and frogs you hear at night?  Those lovely bird songs you wake up to in the morning?  Those are all horny dudes advertising their availability to potential mates.  It is possible lambiosaurid dinosaurs practiced similar behaviors.  Since several different kinds of these duckbills would have lived in the same place during the same time (Corythosaurus and Parasaurolophus, for instance.), it would make sense that each would have different crests to make different sounds and thus, preventing any identity confusion just like all the kinds of birds within a community each have their unique calls today. 

Corythosaurus skeleton, which includes patches of skin and other soft tissue, on display at the American Museum of Natural History in New York.

Corythosaurus is amongst the most well-studied of the non-avian dinosaurs because one specimen that was unearthed in the early 1900s not only included nearly every single bone in the skeleton, but it also preserved skin, organs, and even the animal's last meal!  Thanks to this individual, now on display at the American Museum of Natural History in New York,we know that Corythosaurus would have had pebbly, mosaic-like scales that varied in size to form patterns on its skin.  It also had padding under its feet and hands, which scientists in the early 1900s originally thought would have been webbing for swimming, further supporting the false aquatic hypothesis.  In the stomach cavity were the remains of conifer needles, sticks, and seeds.  These plant foods would have been plucked with Corythosaurus' narrow, flat beak and chewed up with its hundreds of tiny teeth lining the back of its jaws. 

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


Barden, Holly. "Sexual dimorphism in dinosaurs: a review of the evidence and approaches" (PDF). APS 402 Dissertation. University of Sheffield. Retrieved 13 August 2013.

Bell, P. R. (2012). "Standardized Terminology and Potential Taxonomic Utility for Hadrosaurid Skin Impressions: A Case Study for Saurolophus from Canada and Mongolia". In Farke, Andrew A. PLoS ONE 7 (2): e31295. doi:10.1371/journal.pone.0031295. PMC 3272031. PMID 22319623

Dodson, P. (1975). "Taxonomic implications of relative growth in lambeosaurine dinosaurs". Systematic Zoology 24 (1): 37–54. doi:10.2307/2412696. JSTOR 2412696.

Sunday, June 15, 2014

Citipati: Prehistoric Animal of the Week

Hello all!  Happy Fathers Day!  This week we will be keeping good fathers in mind as we take a look at a dinosaur who's remains completely changed the way we looked at not only it, but dinosaurs as a whole as well.  Check out Citipati osmolskaeCitipati was an oviraptorid theropod that lived in what is now Mongolia during the late Cretaceous, roughly 75 million years ago.  It was a fairly large oviraptorid, measuring about ten feet long from beak to tail, and would have eaten meat and possibly some plant material as well.  Citipati's habitat would have been a desert where it coexisted with other dinosaurs such as Protoceratops, Velociraptor, and Oviraptor.

Citipati family goes for a stroll.  Mom leads the way while Dad takes up the rear, making sure none of the kids do anything stupid.

The name, Citipati, translates to "funeral pire lord" and is a reference to a Tibetan folk story.  In the story, two monks were decapitated while they were meditating.  Often times these two monks are depicted in traditional Tibetan art as two skeletons dancing around in fire, called citipati.  Citipati, the dinosaur, is known from many beautifully preserved skeletons and is named in reference to these depictions.

Even in death these guys kept partying.  Good for them.
Citipati was an oviraptorid and belonged to the same general family as Oviraptor and Anzu. Like them, it had a short snout and tall beak.  This beak would have been backed up by extremely powerful muscles which would have enabled this animal to bite down HARD in life.  Like its relatives it possessed no teeth in its mouth, but it did have pointed bone structures on the roof of its mouth that were used to crack...something.  It had a particularly long neck and short tail amongst other members of its family.  It also had a bony crest on the front of its snout.  In life, Citipati, would have had feathers.

Citipati skeletal mount.

Now here is where Citipati gets even more interesting.  Remember last Easter when I talked about Oviraptor and how its name means "egg thief" because it was found near some eggs but the eggs turned out to be its own thanks to another related specimen that was found sitting on a nest of similar looking eggs?  ...Well Citipati was that related specimen!  Back in the 1990s paleontologists discovered the remains of a Citipati that was sitting on a nest of eggs in the exact pose that birds today assume when they brood their own eggs.  It's actually quite beautiful and tragic if you think about it.  This poor parent dinosaur's instincts were so strong that it remained on its nest even if it meant being swallowed up by a sandstorm.  The result is a fossil that gave scientists more information about dinosaurs as a whole, let alone Citipati, than they ever could have imagined!

Famous brooding Citipati fossil display at the American Museum of Natural History in New York.  You can make out how the animal would have been sitting with its legs folded in the middle and its arms spread over the eggs when it died.

So what exactly can we gather from this Citipati fossil?  Like I stated before, upon looking inside some of the eggs, and by comparing them to other eggs that have been found in the area, it was concluded that Citipati and its kin were caring parents and totally undeserving of their "egg thief" name.  (Although they may have eaten the eggs of other dinosaurs too even though no evidence suggests it as of now...eggs are nutritious!)  It also solidified the modern bird's connection to other dinosaurs thanks to the pose this parent had died in.  The last bit of information wasn't so obvious.  If you look at the fossil, you will notice that the parent's body with the arms out to the sides still doesn't completely cover the eggs as it is.  If it had arm feathers, however, all the eggs would have been perfectly guarded under a nice, plumed roof...just like modern birds.  This fossil, even though no actual feathers were preserved, brought us that much closer to the eventual realization that many theropod dinosaurs had feathers in life.

So what does this all have to do with Fathers Day?  Well, it is often assumed that the Citipati sitting on the nest was a female.  But what if it was the male?  There sadly isn't any evidence that favors the adult specimen being either sex.  If we look at living dinosaurs that have similar lifestyles as Citipati may have had, however, we do see some hints.  I'm talking about large flightless birds like ostriches, emus, cassowaries, and rheas.  (I actually get to see rheas every day at work at the zoo.  They are nothing short of living dinosaurs!)  Many of these kinds of birds are what we call polyandrous.  That means one female will mate with multiple males.  In the case of both ostriches and rheas, it is the males who build nests.  Then the female goes around to each one and deposits some eggs. (not all of which are necessarily from that particular father)  Each father then proceeds to brood the clutches much in the same way the Citipati was found doing to its own millions of years ago.  When the babies hatch out, father raises them until they are old enough to be independent.  Yay for dinosaur dads!

That's dad!  The male ostriches have the striking black and white feathers.  Females are brown.

Am I saying that the Citipati found on the nest was definitely a male?  No.  I am saying that we don't know and assuming it was dad and not mom is as good a guess as any right now, especially when you look at the modern evidence.

That's all for this week!  Happy Fathers Day to all the dads out there!  If you have any requests or comments please do so below or on our facebook page


Clark, J.M., Norell, M.A., & Barsbold, R. (2001). "Two new oviraptorids (Theropoda:Oviraptorosauria), upper Cretaceous Djadokhta Formation, Ukhaa Tolgod, Mongolia." Journal of Vertebrate Paleontology 21(2):209-213., June 2001.

Norell, M.A., Clark, J.M., Chiappe, L.M., and Dashzeveg, D. (1995). "A nesting dinosaur." Nature 378:774-776.

Norell, M. A., J. M. Clark, D. Dashzeveg, T. Barsbold, L. M. Chiappe, A. R. Davidson, M. C. McKenna, and M. J. Novacek (1994). "A theropod dinosaur embryo, and the affinities of the Flaming Cliffs Dinosaur eggs." Science 266: 779–782.

Osborn, H.F. (1924). "Three new Theropoda, Protoceratops zone, central Mongolia." American Museum Novitates, 144: 12 pp., 8 figs.; (American Museum of Natural History) New York. (11.7.1924).

Varricchio, D.J. (2000). "Reproduction and Parenting," in Paul, G.S. (ed.). The Scientific American Book of Dinosaurs. New York: St. Martin's Press, pp. 279-293.

Monday, June 9, 2014

Quetzalcoatlus: Prehistoric Animal of the Week

This week's prehistoric animal was requested by our good friend, Joe!  Check out Quetzalcoatlus northropi!  If Tyrannosaurus rex was the king of the dinosaurs, then Quetzalcoatlus was definitely the king of the pterosaurs.  Not only was Quetzalcoatlus likely the largest pterosaur, but it was also likely the largest animal to ever fly!  Its wingspan was up to thirty six feet wide and while standing on the ground it could have stood between fifteen to twenty feet tall! It would have been able to stare a Tyrannosaurus rex in the eye (Right before getting its head chomped off but that's besides the point.)  It lived in what is now Texas, USA, during the late Cretaceous, 68 million years ago.  When alive, it coexisted with many dinosaurs such as Ankylosaurus, Anatotitan(Edmontosaurus), Dracorex, Pachycephalosaurus, Anzu, Troodon, Triceratops...*BREATH*...and Tyrannosaurus during a time within the Cretaceous called the Maastrichtian era.   The genus name, Quetzalcoatlus, is in reference to the ancient Central American god, Quetzalcoatl who took the form of a feathered snake. (strangely not the weirdest mythical creature I have heard of)  Feathered snake...flying snake...flying reptile...pterosaur...sounds good to me!  The species name, norhtropi, is in reference to Jack Northrop, the man who's company made large, tailless air crafts which sort of look like giant pterosaurs.

Quetzalcoatlus northropi by Christopher DiPiazza.

Now here's the thing about Quetzalcoatlus...See, all that stuff up there I just told you?  All the measurements like wingspan and height?  I bet you think we have plenty of fossils to work with from this guy.  How could we not?  It is easily one of the most popular pterosaurs by far.  In actuality the big Quetzalcoatlus northropi is only based on one left wing discovered in the 1970s...that's it.  Everything else we think we know about this animal is based on fossil material that has been gathered over the years from related species.  There is another species of Quetzalcoatlus that was a great deal smaller that has some skull material, and then there is a related animal, called Hatzegoptyeryx, from Europe that scientists believe was very similar to Quetzalcoatlus. (Some believe that the two may even be the same species.) So everything that I am going to tell you in this post is actually educated guesswork based on material from all over the world!  Did that hurt?  I know, I'm sorry.  This is even worse than finding out Santa wasn't real.  If you look at artwork of Quetzalcoatlus starting in the 70s you will see drastic changes in the animal's image as the years go on based on new fossil material that was discovered and applied along the way from related species.

Quetzalcoatlus arm on display at the American Museum of Natural History.

Quetzalcoatlus belonged to a family of pterosaurs called Azhdarchidae.  These were the last and largest pterosaurs to exist before going extinct sixty five million years ago.  They also had some of the oddest proportions of any animal.  The heads possessed large, toothless beaks at the end of long, stiff necks.  Their bodies were proportionally tiny, only about a third the length of their heads!  Their wings were also proportionally shorter when compared to those of some other large pterosaurs (the wing finger was less than half the length of the whole arm), but they were still able to fly quite well.  They also likely had crests on their heads considering that so many other pterosaurs had them, but the exact shape is unknown.  According to what we think we know, Quetzalcoatlus would have been a predator in its environment, hunting small animals like mammals and small dinosaurs.  Despite its ability to fly, it would have also been very comfortable walking on the earth on its four stilt-like limbs.  It may have stalked along the ground, striking any prey with its massive beak much like modern storks, hornbills, and herons do today.  However, the neck of an azhdarchid was not very flexible, and the motion was probably more similar to that of a dipping bird toy...a twenty foot tall dipping bird toy from hell!

Sketch of Quetzalcoatlus walking.

Like I said earlier, Quetzalcoatlus did fly.  You may be wondering how an animal that big was able to ever get off the ground, though.  In fact, only a few years ago there was a proposal by some paleontologists saying Quetzalcoatlus and some of its relatives were actually flightless.  This was later proven to be wrong, however.  See, the arm bones of Quetzalcoatlus were extremely robust and would have anchored HUGE muscles on the chest, back, and bicep areas (experts think about 110 lbs of muscle in these areas to be exact).  We actually see this in a lot of pterosaurs and even modern analogs like bats and birds.  Why would an animal still have all that extra muscle in those places if it wasn't flying?  As it turns out, using the latest technology and fossil information, it was found that Quetzalcoatlus would have actually been a really good flyer, able to stay aloft for several days at thousands of feet above the ground!  The way it would have taken off from the ground also lies in its arms.  Unlike birds, who use their hind legs to launch themselves into the air, pterosaurs had four limbs to do this with, so that's more power right there.  Paleontologists theorize that a taking off Quetzalcoatlus would have looked like someone playing leap frog or pole vaulting.    Check out this video below.  The model isn't Quetzalcoatlus, but it gives the same idea.

That's all for this week!  Hope you enjoyed the largest, yet mysterious, pterosaur!  If you have another request feel free to comment below or on our facebook page!  Also special thanks to Dr. Mark Witton for providing his expert insight on this most grand of pterosaurs!


Henderson, D.M. (2010). "Pterosaur body mass estimates from three-dimensional mathematical slicing." Journal of Vertebrate Paleontology, 30(3): 768-785. doi:10.1080/02724631003758334

Kellner, A.W.A., and Langston, W. (1996). "Cranial remains of Quetzalcoatlus (Pterosauria, Azhdarchidae) from Late Cretaceous sediments of Big Bend National Park, Texas." Journal of Vertebrate Paleontology, 16: 222–231.

Witton, Mark P., and Michael B. Habib. "On the Size and Flight Diversity of Giant Pterosaurs, the Use of Birds as Pterosaur Analogues and Comments on Pterosaur Flightlessness." Ed. Vincent Laudet. PLoS ONE 5.11 (2010): E13982. Web.

Witton, M.P., Martill, D.M. and Loveridge, R.F. (2010). "Clipping the Wings of Giant Pterosaurs: Comments on Wingspan Estimations and Diversity." Acta Geoscientica Sinica, 31 Supp.1: 79-81

Witton, M.P., and Naish, D. (2008). "A Reappraisal of Azhdarchid Pterosaur Functional Morphology and Paleoecology." PLoS ONE, 3(5): e2271. doi:10.1371/journal.pone.0002271

Witton, Mark P. Pterosaurs: Natural History, Evolution, Anatomy. N.p.: n.p., n.d. Print.

Sunday, June 1, 2014

Mantellisaurus: Prehistoric Animal of the Week

If you hadn't noticed, I skipped a week.  I was in London and didn't have access to a computer, sadly.  I would normally apologize but then I would be dishonest, teehee! (London was so fun.  More on that in the near future.)  This week, in honor of my trip, we shall be checking out a dinosaur that is famous (sort will see what I mean just keep reading) for being native to what is now England.  Check out Mantellisaurus atherfieldensisMantellisaurus was a plant-eating, ornithopod dinosaur that lived in what is now Southern England during the Early Cretaceous period about 130 million years ago.  It measured about thirty feet long from snout to tail and would have walked on its hind legs most of the time.  It may have dropped to all fours occasionally when resting.

Mantellisaurus atherfieldensis reconstruction by Christopher DiPiazza.

Mantellisaurus used to go by a much more recognizable genus name, Iguanodon.  During the 1800s and early 1900s most any large ornithopod found in Europe was given the genus name, Iguanodon.  It wasn't until years later that the specimens assigned to Iguanodon were examined more closely and several different kinds of related animals were able to be differentiated within this wastebasket of a genus.  One of these was Mantellisaurus.  Don't worry, the popular Iguanodon still stands.  In fact, the animal now officially holding the name, Iguanodon, has remains found in England, as well.  The best, most complete specimens of this particular genus are all from Belgium, however.  The two animals are very closely related and both had the trademark thumb spike on their hands for defense or combat within their species.  Mantellisaurus differs, however, in that it has much shorter front limbs than back limbs, and likely spent most of its time as a biped.  Iguanodon, on the other hand, actually had very long arms and was probably adept at roaming around on all fours.  Most reconstructions in books and other media that are labelled as "Iguanodon" are actually based on Mantellisaurus. (especially those made before 2007 when Mantellisaurus was officially named)

Mantellisaurus skeletal mount at the London Museum of Natural History.

Mantellisaurus was named in honor of Doctor Gideon Mantell, who was first to discover its (or Iguanodon's?) remains back in the 1800s.  It was Mantell who came up with the name, Iguanodon, which translates to "iguana tooth", due to the dinosaur's teeth resembling that of the modern lizard's.  Like many species of iguana, Mantellisaurus would have used its teeth to shred plant material.  It also had a tough beak in the front of its mouth for clipping.  Its hands, in addition to the thumb spike, had three wide middle digits for walking/standing on, and a flexible pinky digit, that may have helped manipulate vegetation while foraging.  It is because of this variety of different kinds of digits that dinosaurs in the iguanodontid family are said to have had "Swiss army knife hands" by paleontologists.

Remains, tracks, and casts on display at the Booth Museum in London.  These are labelled as belonging to Iguanodon but many, most notably that skull cast, are actually from Mantellisaurus. (which was still included in the Iguanodon genus at the time this exhibit was set up)

That is all for this week!  As always feel free to comment below or on our facebook page!  Stay tuned for some coverage of my trip to London and all the dinosaur-related adventures that went down!


Hooley, W., 1925, On the skeleton of Iguanodon atherfieldensis sp. nov., from the Wealden Shales of Atherfield (Isle of Wight): Quarterly Journal of the Geological Society of London, v. 81, p. 1-61.

Norman, D.B., 2012. "Iguanodontian Taxa (Dinosauria: Ornithischia) from the Lower Cretaceous of England and Belgium". In: Pascal Godefroit (ed.), Bernissart Dinosaurs and Early Cretaceous Terrestrial Ecosystems. Indiana University Press. 464 pp.

Paul, Gregory S. (2008). "A revised taxonomy of the iguanodont dinosaur genera and species". Cretaceous Research 29 (2): 192–216. doi:10.1016/j.cretres.2007.04.009.