Sunday, October 19, 2014

Stygimoloch: Prehistoric Animal of the Week

Halloween is so close!  In honor of my favorite holiday let's check out a dinosaur with a truly horrifying name.  Enter Stygimoloch spinifer!  The genus name, Stygimoloch, translates to "Demon from the River of Death". (called "Styx" in Greek mythology.)  The name is in reference to this dinosaur's rather demonic-looking horns, which covered a lot of its head.  Despite the name and appearance, Stygimoloch was a plant-eater, not a soul-eating beast from the underworld.  Stygimoloch measured about ten feet long from beak to tail and lived during the very end of the Mesozoic in what is now the United States, between 67 and 65 million years ago, during the Late Cretaceous period.  When alive, it lived alongside Tyrannosaurus, Triceratops, Troodon, Anzu, Anatotitan, Ankylosaurus, Pachycephalosaurus, Dracorex, and Quetzalcoatlus.

Stygimoloch spinifer life reconstruction by Christopher DiPiazza.

 Stygimoloch is obviously most noted for it's head, which was practically covered in horns.  Many of the horns, especially on the snout and around the eyes, were small.  On the back of the head were two sets of long horns growing from either side of the rear of the skull.  On the top of the head, Stygimoloch was armed with a small oval-shaped mass of solid bone.  Paleontologists debate as to what exactly all of this interesting ornamentation was for.  Many believe they were weapons, and that Stygimolochs would have rammed or pushed each other for dominance, or possibly defended themselves against predators with their heads.  Others believe they were only for display.

Stygimoloch skull on display at the Museum fur Naturkunde in Berlin.

Stygimoloch also had a relatively long snout, tipped with a short beak.  This beak was probably good for clipping soft vegetation, which would have then been shredded up in the back of the mouth with its small teeth.  Some suggest Stygimoloch and its relatives would have actually eaten meat in addition to plants in the form of small animals or possibly carrion, but this idea is highly debatable.  Stygimoloch also had large eye sockets and likely had good vision, which is common to members of its family, the pachycephalosaurids. 

Relatively recently, some paleontologists have suggested that Stygimoloch was actually the same species as Dracorex and Pachycephalosaurus.  According to this hypothesis, Dracorex was a juvenile Pachycephalosaurus, having not developed a dome in its young age, Stygimoloch would have been a young adult, having developed a small dome, and Pachycephalosaurus was the mature adult, with a full dome but shorter horns.  Despite this idea's popularity, it is highly debatable and challenged by many other paleontologists.  The idea of long horns shortening and forming a dome needs to be looked into more since nothing like it can be observed in any other large vertebrate. 


Carpenter, Kenneth (1997). "Agonistic behavior in pachycephalosaurs (Ornithischia:Dinosauria): a new look at head-butting behavior". Contributions to Geology 32 (1): 19–25.

Galton, P. M. and H. D. Sues (1983). "New data on pachycephalosaurid dinosaurs (Reptilia: Ornithischia) from North America." Canadian Journal of Earth Sciences 20: 462-472.

Goodwin, M. B., E. A. Buchholtz, et al. (1998). "Cranial anatomy and diagnosis of Stygimoloch spinifer." Journal of Vertebrate Paleontology 18(2): 363-375.

Horner J.R. and Goodwin, M.B. (2009). "Extreme cranial ontogeny in the Upper Cretaceous Dinosaur Pachycephalosaurus." PLoS ONE, 4(10): e7626.

Maryańska, Teresa; Chapman, Ralph E.; Weishampel, David B. (2004). "Pachycephalosauria". In Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.). The Dinosauria (2nd ed.). Berkeley: University of California Press. pp. 464–477. ISBN 0-520-24209-2.

Wednesday, October 15, 2014

National Fossil Day 2014

Happy National Fossil Day!  This year I would like to share with you some videos Gary and I took this past summer, while doing fieldwork in New Mexico, that we feel give you a little taste of what it is like to prep fossils.  We have already shown you videos of excavating the amazing finds out in the field, but that's only half the battle.  (If you haven't seen those posts yet be sure to check out what we did back in 2013, this past summer in 2014, and definitely check out Gary's step-by-step story on excavating a Typothorax rib from the earth to the display case!)  A huge part of working in paleontology requires prepping fossils in a lab setting.  This work isn't so much strenuous, but it is tedious at times.  Ever wonder why new fossil species sometimes take years to be published after they are discovered?  It's because sometimes it takes that long for them to be prepped! 

We can use a variety of different tools to help us prep fossils.  One great piece of equipment we use to remove large amounts of rock from around the fossils is called an air scribe.  This device is essentially a pen-sized jackhammer.  Below is a video of Gary using one of these air scribes to get through a rather large rock for the sake of a rather small (but important) fossil. 

Using an air scribe takes some practice to get comfortable with.  Once mastered, however, it makes prepping fossils a lot easier!  It still can take many hours to get the prize out of the rock, however.  Imagine how long it must have taken paleontologists to prep fossils before they had air scribes!

Once out of the rock, the fossils still need some attention before they are museum/publication ready.  These tools are for more detailed work than an air scribe and take just as much patience to use properly.  In the lab, we use everything from dental tools, toothbrushes, paintbrushes, and of course, Q-tips.  Many times, unfortunately, the fossil will break while being cleaned.  This is pretty common and happens to the best of us.  Luckily we have plenty of adhesives in the lab to put them back together.  Sometimes, unfortunately, the particularly small fossils can splinter apart to the point of no repair.  The best one can do in this situation is just chalk it up to a learning experience and be even more careful on the next one!  Check out this video of me as I clean off some of these tiny, yet awesome, fossils from the Triassic! 

Hope you enjoyed a taste of fossil prepping!  On a slightly different note, I was given the opportunity to run the Bergen County Zoo's first annual fossil day!  It's no Smithsonian, but I did my best to make the education center as full of fossil education as possible.  This temporary exhibit featured real fossils, fossil replicas, a (small) portion of my dinosaur toy model collection, and plenty of my original artwork.  Some illustrations I created special for this event.  I even got to use the zoo's brand new touch board device!  Below are some photos I took of the room after the zoo closed and the masses had left.  Enjoy!

Some of those Redondasaurus teeth in the case were in the video you just watched.
Same goes for some of those Typothorax bits.

Sunday, October 12, 2014

Rhinorex: Prehistoric Animal of the Week

This week let's look at a species of dinosaur that was unveiled only a few weeks ago!  Check out Rhinorex condrupusRhinorex was a plant-eating dinosaur that lived in what is now Utah, USA, during the late Cretaceous Period about 75 million years ago.  It was a hadrosaurid, in the same family as other broad-billed duck-billed dinosaurs like Maiasaura, Anatotitan, and Hadroaurus.  From snout to tail it would have measured about thirty feet long.  The genus name, Rhinorex, translates to "Nose king" in reference to this dinosaur's large, down-turned snout.  Other duckbills have been found with similarly-shaped snouts, but none as extreme as Rhinorex's.  When alive, Rhinorex would have lived nearby other dinosaurs such as Coahuilaceratops, Teratophoneus, and its close relative, Gryposaurus.

life reconstruction of Rhinorex condrupus by Christopher DiPiazza.

Scientists are still not completely sure as to why Rhinorex had such a large nose.It may have been an adaptation for a specific feeding strategy.  It also may have been a display adaptation for attracting mates or intimidating rivals.  It may have even enabled Rhinorex to make certain sounds.  Lambiosaurine hadrosaurs like Corythosaurus, Parasaurolophus, and Tsintaosaurus, possessed crests on the tops of their heads for display and sound purposes.  It is possible that the lineage Rhinorex was from just applied the strategy to a different part of the skull. 

Reconstruction and photograph of Rhinorex skull.  Image from the recent paper, describing Rhinorex, by Terry Gates and Rodney Scheetz.

Rhinorex was the only well preserved dinosaur fossil found from its specific area thus far.  In addition to it's skull there was also some skin impressions found, which look similar to other known hadrosaur skins; fine pebble-like scales.  All other dinosaur fossils in Utah from the same time period were found hundreds of miles away and would have likely been adapted to a different kind of habitat.  Rhinorex helps fill in gaps previously unknown about Late Cretaceous ecosystems in Utah. 

That's all for this week!  As always feel free to comment below or on our facebook page!  Have a request?  Just let me know and I'll make it happen!


T.A. Gates & R. Scheetz (2014): A new saurolophine hadrosaurid (Dinosauria: Ornithopoda) from the Campanian of Utah, North America Journal of Systematic Paleontology. doi: 10.1080/14772019.2014.950614

Thursday, October 9, 2014

Fossil Day at the Zoo

Sunday, October 12th, 2014, I am running the Bergen County Zoo's first ever Fossil Day event!  Come on down and see some real fossils and hear about Gary and I's experiences hunting for them!  Did I also mention it's at a zoo...with animals?  COME ON GO GO GO GO!

Sunday, September 28, 2014

Chunerpeton: Prehistoric Animal of the Week

This week we honor a prehistoric amphibian that has ties to animals that are near and dear to my heart today.  Check out Chunerpeton tianyensisChunerpeton is one of the first known salamanders to ever appear in the fossil record.  It lived during the Jurassic Period, about 160 million years ago, in what is now China.  It measured about seven inches long on average, and like its living relatives, would have been a predator, capturing and swallowing whole any small animal it could fit in its mouth.  The genus name, Chunerpeton, translates to "Early Creeper".  When alive, Chunerpeton would have lived nearby some dinosaurs like Anchiornis and Eosinopteryx.

Life reconstruction of Chunerpeton tianyensis by Christopher DiPiazza. I opted for no gills since all its living relatives don't have them as fully grown adults.

Chunerpeton is known from hundreds of well preserved fossils.  During the Jurassic, the lake in which these Chunerpeton lived was buried under a layer of ash when a nearby volcano erupted, preserving them all to eventually become wonderfully preserved fossils.  Many specimens retain skin, eyes, stomach contents (included small shrimp in case you were wondering) and external gills.  The fact that Chunerpeton is known from all the way back during the Jurassic is amazing.  Before its discovery only a few years ago, the oldest known salamander fossils were from only about 65 million years ago, not long after the great Mesozoic extinction that wiped out most of the dinosaurs.  Of course other kinds of amphibians have been around since MUCH earlier, but Chunerpeton was the first occurrence of a true salamander like we see around us today. 

Chunerpeton fossil.  You can see where external gills would have been just behind the skull.

What kind of salamander was Chunerpeton though?  Scientists identified it as a member of the salamander family, cryptobranchidae.  Modern examples of cryptobranchids are the largest living amphibians, like the Chinese Giant Salamander. (Andrias davidianus)  The highly endangered Hellbender (Cryptobranchus alleganiensis) from North Eastern United States is also a cryptobranchid.  Chunerpeton is also closely related to another family of modern salamander, called hynobidae.  Both hynobids and cryptobranchids spend most of their time in cool, clean water, and are voracious predators, snapping up any kind of prey that wanders too close to their mouths.  Like most amphibians, they start out as a fully aquatic larval form with gills.  As they age they lose the gills and gain the ability to breathe air but still prefer to spend most of their time in the water.  It is likely Chunerpeton was the same way.  Many Chunerpeton fossils, like I stated earlier, preserved external gills.  This leaves many to believe that Chunerpeton retained its gills into adulthood, which is exhibited in some kinds of modern salamanders.  These fossils could also just be of juveniles, however.

My pet Hynobius dunni begging for food at the front of the tank.

 Like I shared a few days ago, I personally keep many salamanders in my home as pets.  Amongst them I do have one kind, a hynobid, that is closely related to the ancient Chunerpeton.  It is called a Japanese Oita Salamander. (Hynobius dunni)  Quite a little cutie!  He eats worms and crickets right from my fingers too!

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


Ke-Qin Gao & Neil H. Shubin (27 March 2003). "Earliest known crown-group salamanders". Nature 422 (6930): 424–428. doi:10.1038/nature01491.

Roach, John. "China Ash Yields Salamander Evolution Secrets." National Geographic. National Geographic Society, 28 Oct. 2010. Web.

Steyer, Sebastien. Earth before the Dinosaurs. Bloomington: Indiana UP, 2012. Print.