Tag Archives: ornithischian

Know Your Bones: July 2015

I chose last month’s challenge believing it would be a tricky one. However, I was truly impressed by the answers given, although none of them were correct, but the knowledge of prehistoric critters the readers of this blog possesses impresses me. I truly thought everyone would simply guess Triceratops and move on. As I said, this is not Triceratops, nor any of the ceratopsians given in the comments. Thus, this once again makes me the winner of this month’s challenge for stumping everyone.


However, the critter that owned the skull in last month’s challenge was Pentaceratops sternbergii and I will give you five guesses as to what its name means.


 photo Dayatthemuseum001_zps5d38b135.jpg
(Taken at the New Mexico Museum of Natural History and Science)


Pentaceratops lived during the Cretaceous 75 to 73 million years ago. It is mostly found in New Mexico and Colorado (U.S.). It would have reached a length of ~8 meters and weighed ~5,500 kg. Pentaceratops had five horns, two large horns over the eyes, one small horn over the nose, and two small horns, which protrude sideways out of under the eyes. Pentaceratops also possessed a large frill with two large fenestrae in it. The fenestrae found on the frill were most likely away for cutting down the weight of the skull. Pentaceratops specimens include some of the largest skulls of all terrestrial animals. The frill and horns were most likely used for display, with the possibility of blood being pumped into the frill to change its color slightly. The frill and horns were also probably used in defense as well as jousting between each other.


Pentaceratops belongs to the ceratopsian clade. That clade also belongs to the ornithischian clade, meaning that Pentaceratops and the other ceratopsians are more closely related to hadrosaurids and thyreophorans than they are to saurischians. Pentaceratops is believed to be an herbivore and thought to have traveled in large herds similar to modern bovines. Another striking feature Pentaceratops possesses is its sharp beak, which was most likely used for ripping open large and tough vegetation or digging into the ground for tubers.


Moving on to next month’s challenge:


 photo IMAG0167_zps074c8041.jpg
(Taken at the Denver Museum of Nature and Science)


Here is an easy one, since last month’s challenge ended up being so difficult. I am looking for the critter on the left, since the critter on the right was already featured. Good luck to all that participate.

Know Your Bones: December 2014

Last month’s challenge was not very challenging seeing as how Isotelus was able to give the correct answer within hours of when the blog was posted. She said it gave her some trouble, but I actually highly doubt that.


Partial skull of Parasaurolophus. I would say P. tubicen because the crest is a bit different from P.walkeri, and it’s definitely not P. cyrtocristatus. Also it’s from New Mexico so it makes sense to be in the NM museum. SCIENCE.


This skull did indeed belong to Parasaurolophus tubicen, which stands for trumpeter-crested lizard.


(Taken at The New Mexico Museum of Natural History and Science)


Parasaurolophus are extremely rare animals in the fossil record. There are three species known to science found in Alberta (Canada), New Mexico (USA), and Utah (USA). In each area, only a few specimens have been found and all specimens are incomplete. P. tubicen is only known from New Mexico with three specimens discovered. Parasaurolophus lived during the Late Cretaceous 76 to 73 million years ago. P. tubicen reached a size of ~9.5 meters in length and weighed ~ 2.5 tons. P. tubicen was an herbivore and most likely walked on four legs, but was able to run, walk, and brows on its hind limbs.


Even though it is rare, it is still one of the most famous dinosaurs, and that is most likely due to the eye-catching aspect of P. tubicen. The crest that grows from the rear of its skull is fairly unique. The crest is hollow and allowed air to be pushed through it. This would have allowed P. tubicen to make very loud trumpeting noises. The crests were also most likely colorful and could have acted as visual displays. P. tubicen would have filled the Late Cretaceous with beautiful music while communicating with one another over large areas. P. tubicen belongs to the hadrosaurid clade, which is one of the most famous ornithischian clades as well.


Moving on to this month’s challenge:


(Taken at the New Mexico Museum of Natural History and Science)


Good luck to everyone that plays.


Know Your Bones: May 2014

Last month’s challenge was extremely easy, so easy in fact that just an hour after being posted Inferno gave a correct answer. However, and this seems to be a theme for this series, WarK posted an even more correct answer a few hours later.


 Stegosaurus stenops

I’m guessing with the latter part of the name. From what pictures I could find online that one looked the closest to the picture posted by the Bone Torturer


This is indeed Stegosaurus stenops, a very famous dinosaur.



(Taken at the New Mexico Museum of Natural History and Science)


Stegosaurus ranged across most of western North America during the late Jurassic 150 to 145 million years ago, and one specimen was discovered in Portugal. Stegosaurus is found in the Morrison Formation in North America. Stegosaurus stenops could reach a size of ~7 meters in length, although some species of Stegosaurus could reach lengths of ~9 meters. This sounds impressive, but one has to remember that Stegosaurus would have been dwarfed by the sauropods found at the same time and place.



(Taken at the New Mexico Museum of Natural History and Science)


There are two main branches of dinosaur, ornithischians (“bird” hip) and saurischians (“lizard” hip). Stegosaurus belongs to the ornithischian clade. This means that Stegosaurus possesses a pelvis that superficially resembles a modern bird pelvis. Stegosaurus also belongs to the Thyreophora (armored dinosaur) clade. This clade includes all the dinosaurs that had armored backs and tales. The plates found on the back of Stegosaurus and the spikes on its tale make Stegosaurus one of the easiest dinosaurs to identify. The spikes on its tale were most likely exclusively used as defensive weapons against the predators of its time. However, the plates on the back of Stegosaurus may have been used for thermal regulation as well as defense. The plates show blood vessels ran across their surface. This could have also been used for colorful displays when blood was pumped into them.


Moving on to this month’s challenge:


(Taken at the New Mexico Museum of Natural History and Science)


Good luck.