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Sunday, August 25, 2013

Anatotitan: Prehistoric Animal of the Week

Today we are checking out one of the largest and most well studied of the duck-billed dinosaurs.  Enter Edmontosaurus annectens!  This plant eating dinosaur grew to be almost forty feet long from head to tail and lived 68 to 66 million years ago during the late Cretaceous in what is now the western United States of America.   Specifically, its remains have been found in Montana, South Dakota and Wyoming.  When alive this dinosaur would have co-existed with other famous animals such as Ankylosaurus, Triceratops, Pachycephalosaurus and Tyrannsoaurus

Life reconstruction of Edmontosaurus annectus by Christopher DiPiazza.

Yes, I put a different genus name for the title.  This dinosaur has gone through a bit of an identity crisis over the years having its genus name changed more times than something that typically changes a lot (I'm off my game with analogies today okay?...or with ANAT-ogies OH YEAH! My pun ability is just fine though).  In the past this dinosaur has been named Anatosaurus, Trachodon, Anatotitan and now has been lumped with the genus previously thought to be separate, Edmontosaurus.  I would like to do a different species of Edmontosaurus in the future so I figured no harm in using Anatotitan for this post.  Anatotitan translates to "titan duck" (way cool) and Edmontosaurus translates to "Edmonton reptile/lizard" (because another species of this genus was first discovered there.  Appropriate, but not as cool sounding).

Skeletons on display at the American Museum of Natural History in New York City.  These tail-dragging poses are not considered accurate anymore.

Out of all the duck billed dinosaurs, also known as hadrosaurs which are characterized by having wide, flat bills in the front of their mouths, Anatotitan had the "duckiest" bill.  It was particularly wide and almost angular to a degree.  This is a great adaptation for an animal that needed to eat a lot of plant material.  The wider an animal's mouth, the more foliage it can get in each bite.  To be honest, the bill of a hadrosaur, even Anatotitan, isn't really all that similar to that of an actual duck's (which is adapted for sifting through water and lined with ridges on the inside).  Beyond the bill there were hundreds of tiny teeth all packed together to form a solid unit called a dental battery.  This was a great adaptation for grinding and chewing the tough pine needles which it would have eaten (at least its breath was probably fresh!).  Anatotitan would have walked on all fours but was capable of rising up and running on its hind legs if it wanted to move more quickly.

Fossilized skin from "Dakota".

There has been a mummified specimen of an Anatotitan found!  Back in the early 2000s a high school student named Tyler Lyson discovered a beautifully preserved Anatotitan fossil that still had muscle and skin.  Shortly after, paleontologist, Phillip Manning, was responsible for excavating and studying this amazing find.  We now know thanks to this mummy (which had turned into fossilized rock) that Anatotitan would have had a thick, powerful tail and neck.  It was also probably able to run faster than what most scientists had previously thought (faster than a T. rex even...how convenient).  The scales on this specimen, nicknamed "Dakota" because of where it was found, were like tiny mosaics of differing sizes.  The different sizes formed patterns that may reflect a color pattern the animal would have sported when alive.  Assuming this is true, this dinosaur would have had darker bands going down its tail.

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

References

Brett-Surman, Michael K. (1979). "Phylogeny and paleobiogeography of hadrosaurian dinosaurs". Nature 277 (5697): 560–562

Campione, Nicolás E.; and Evans, David C. (2011). "Cranial growth and variation in Edmontosaurs (Dinosauria: Hadrosauridae): implications for latest Cretaceous megaherbivore diversity in North America". PLoS ONE 6 (9): e25186. 

Lambe, Lawrence M. (1917). "A new genus and species of crestless hadrosaur from the Edmonton Formation of Alberta" (pdf (entire volume, 18 mb)). The Ottawa Naturalist 31 (7): 65–73. Retrieved 2009-03-08.

Lambe, Lawrence M. (1920). "The hadrosaur Edmontosaurus from the Upper Cretaceous of Alberta". Department of Mines, Geological Survey Memoirs 120: 1–79. 

Ostrom, John H. (1964). "A reconsideration of the paleoecology of the hadrosaurian dinosaurs". American Journal of Science 262 (8): 975–997


Thursday, August 22, 2013

The Most Horrid Mythical Creature: TERRORDACTILE

Since dinosaurs and certain other prehistoric creatures are so inspiring to humans, it should be no surprise that their images come up all the time in pop culture.  Movies, TV shows, video games, toys...the list goes on.  Sometimes the artists depicting the said dinosaur for some of these doesn't always know all the facts and what the final product ends up being is sometimes less than perfect.  Personally this doesn't really irk me as much as it does some other people.  Of course I care about science and all that but I'm not the snobby type to be a science perfectionist towards something like a science fiction movie! (I only get annoyed when places that claim to be science-based are not)

That being said it is still a lot of fun to point out some of the more extreme monstrosities! 

Pterosaurs have been popular in pop culture as long as humans have known about them.  I find it funny how so often they are portrayed usually even less accurately than dinosaurs.  Pterosaurs are known for being able to fly but beyond that (anatomy, physical ability) a lot of people don't know much about them.  For instance a pterosaur, even one of the largest ones (which were about the size of a small plane) couldn't lift something the size of a human.  They were too light and their feet couldn't grasp like an bird of prey's.

 

Oh and another thing.  Did you see the wings on that creature?  They look a lot like a bat's don't they?  Pterosaurs didn't have wings like that.  A bat's wing is basically just the animal's hand with elongated fingers which are webbed.  The fingers act like supports, somewhat like the metal rods on an umbrella, to give the wing shape and also to control when the wing opens, closes and how it flaps.

See?  The thumb is free and the other four fingers form the wing!  Bats are cool mammals.

Pterosaur wings are a little different.  A pterosaur's wing is supported by just one long finger.  There are three more but they are small, free, and probably were used for walking and/or climbing depending on the specific pterosaur.

Three free fingers and one finger supports the wing.

Sometimes pterosaurs are given teeth that they wouldn't have had in life.  Now keep in mind there were many pterosaurs out there that DID have teeth.  Big ones, too sometimes.  However, the most popular pterosaur in pop culture, called Pteranodon, did not.  Its name even means "toothless wing".


Pteranodon longiceps skeleton.  This is the species most people are familiar with but may not know the actual name of.

So instead of leaving Pteranodon the way it is (which is plenty cool) or just using a different kind of pterosaur that actually had teeth, movie makers, toy designers and other such artists sometimes instead decide to just give poor Petrie a big ol' set of pearly whites.

Pteranodon from the movie, Jurassic Park 3 with a set of sharp chompers.

Oh and you don't even want to KNOW some of the toys of pterosaurs that they have come up with...actually you totally do its hilarious and awesome.

I dunno...
Probably supposed to be Pteranodon but look at that long tail!
Another Pteranodon with teeth AND a long tail.
Pterosaurs with the wings of bats again.

Which brings us to these gems I picked up at a wildlife center gift store.  These toys have been around forever.  Foam plane-shaped toys with the plastic piece you stick on the front then toss and they glide.  They come as planes, birds and...horribly ugly pterosaurs.  There were four different ones.  Pteranodon at least had the head right.  Rhamphoryncus and Dimorphodon looked more or less the same from the outside packaging (both pretty wrong) and then we have Pterodactylus which looked like the artist just gave up and decided to draw a zombie dragon that would be more at home in the cover art of a metal album than in the Jurassic.

I bought these two because Dimorphodon is my favorite pterosaur and the Pterodactylus was just so strange-looking.  I actually want to go back and buy the other two and make a hanging mobile with them.

They do glide pretty well though.  My trusty Yorkshire Terrier monster-attack-beast, Zeus, and I took advantage of the sunny weather and decided to give them their first flight.  Zeus was not amused though. 


For more on Skeletal pterosaurs and dinosaurs check out my friend Marc's post on our friend-blog.  (is friend-blog a real phrase?...eh well I just used it)  So all these ugly pterosaurs inspired me.  I got thinking what if they are just a modern kind of fantasy creature?  You know like the ones from ancient mythology that are made up of parts of different animals like the centaur, griffin or cockatrice?  Then I got my drawing pad out and speed-painted the modern monster.  Behold the TERRORDACTILE!

I also decided to give it sonic brain-scrambling screeching powers.  Deal with it.

This past week I have been going through a pterosaur phase if you hadn't noticed from this post and the latest prehistoric animal of the week.  It's mostly because I finally got around to buying paleongologist and friend of the site's, Mark Witton's new book which is appropriately named PTEROSAURS.  I haven't finished reading the whole thing yet but so far I like it and the illustrations are great too.  You can get one here.

That's all for today!  Tune in Sunday for another prehistoric animal of the week! 

Sunday, August 18, 2013

Pterodactylus: Prehistoric Animal of the Week

"Pterodactyl" is a term thrown around by many to describe all kinds of prehistoric flying reptiles called pterosaurs by folks who don't know any better.  Today we will learn about the true owner of this overused term.  Enter Pterodactylus antiquus

Life reconstruction of Pterodactylus antiquus by Christopher DiPiazza.

Pterodactylus lived in what is now Germany during the late Jurassic Period roughly 150 million years ago.  Fossils believed to belong to Pterodactylus have also been found in other parts of Europe as well as in Africa.  Pterodactylus is a well studied animal that is known from many specimens from small juveniles all the way up to adults with over three-foot wingspans.  Many of these specimens are fully articulated skeletons.   

Evidence shows, thanks to a healthy amount of individual specimens, that Pterodactylus would have grown relatively slowly.  From what the fossils show, a Pterodactylus would have been adult size at about two years of age but would continue to slowly grow throughout its life much like many other reptiles including modern crocodiles and turtles.  This is very different from the growth patterns of birds, which are full size usually within one year of hatching.  I feel it is important to mention that pterosaurs are most definitely NOT the same as birds even though they seem similar and would have occupied some of the same niches that birds do today. 

Pterodactylus fossil
 

Pterodactylus was one of the earliest known pterosaurs from the group, called pterodactyloidae, possessing proportionally large heads and short tails.  All earlier known pterosaurs not belonging to this group had long tails and shorter necks.  (check out Dimorphodon for a comparison) 

Pterodactylus was the first ever discovered pterosaur to be recognized by science back in the late 1700s and was at first believed by scientists to have been a sea creature and that the wings were used like fins!  It wasn't until the year 1800 that Pterodactylus was properly identified as an animal adapted for flight.  For a while after that every new kind of pterosaur that was discovered was lumped into the same genus and therefore were all called "pterodactyls".  Unfortunately this term is thrown around by many people when referring to any kind of pterosaur even today!  However it is from Pterodactylus that the name describing the entire group of flying reptiles, the pterosaurs, comes from.  This is fitting not only because Pterodactylus was the first to be discovered but also because its name translates to "wing finger" which is a defining morphological characteristics for all members within the pterosaur group.  (All pterosaurs have wings made up of a skin membrane attaching from one super elongated fourth finger down to the leg.) 

Just a little pterosaur humor.

Although famous for being able to fly, there is strong evidence that Pterodactylus was comfortable walking on the ground as well.  It may have fed by wading in shallow water plucking small prey with its long jaws which were lined with many sharp, cone-shaped teeth.  This makes sense since the environment Pterodactylus was living in was near salt and perhaps brackish water where having a niche similar to that of a modern wading bird would work nicely.

That's all for this week!  As always don't hesitate to comment below or on our facebook page!  I am always happy to cover requests.

References

Bennett, S.C. (1996). "Year-classes of pterosaurs from the Solnhofen Limestone of Germany: Taxonomic and Systematic Implications". Journal of Vertebrate Paleontology 16 (3): 432–444. doi:10.1080/02724634.1996.10011332.

Bennett, S. Christopher (2013). "New information on body size and cranial display structures of Pterodactylus antiquus, with a revision of the genus". Paläontologische Zeitschrift. in press. doi:10.1007/s12542-012-0159-8

Taquet, P., and Padian, K. (2004). "The earliest known restoration of a pterosaur and the philosophical origins of Cuvier's Ossemens Fossiles". Comptes Rendus Palevol 3 (2): 157–175. doi:10.1016/j.crpv.2004.02.002

Wellnhofer, Peter. The Illustrated Encyclopedia of Pterosaurs. New York: Crescent, 1991. Print.

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

Wednesday, August 14, 2013

Reunited: Morrison Meat Eaters

Lets do another art-related post!  Hey!  Remember a little over a year ago Allosaurus was our Prehistoric Animal of the Week?  Of course you do!  Well here is the painting that was featured again.


And then exactly one year later we said hello to Torvosaurus.  Surely you remember that one.  It was only a few weeks ago!


Well did you know that other than being on the same date a year apart, these two paintings actually have something else in common?  In fact, they aren't two paintings at all.  They are each a part of one larger painting!


There are some other cool animals in this scene too.  In the foreground we have the interesting Ceratosaurus, a few of the bird-like Ornitholestes, a whole bunch of the small pterosaurs, Pterodactylus and one very big, very dead, Apatosaurus.  Cool, huh? 

Sunday, August 11, 2013

Orthacanthus: Prehistoric Animal of the Week

Shark week is over so lets say farewell to every nerd's favorite week of summer by checking out a truly fascinating-looking prehistoric shark.  Enter Orthacanthus!  This shark actually lived in fresh water swamps throughout what is now the Northern Hemisphere as far back as the Devonian (400 million years ago) through the end of the Permian Era (260 million years ago).  There are a few species within the genus, Orthacanthus, but they are all relatively similar to one another.  The fact that a genus of animal can last 140 million years is impressive but then again sharks are known for that sort of thingOrthacanthus grew to about ten feet long and belongs to the family of sharks called Xenacanths that was prevalent during this long time span.

Orthacanthus senckenbergianus life reconstruction by Christopher DiPiazza.

Orthacanthus doesn't really look like many sharks alive today.  Its body was much longer and more slender and it had a shallow, rounded dorsal fin running from the back of its head all the way down to the base of its tail instead of the famous triangle fin we commonly associate with sharks.  These physical characteristics gave it the appearance of an eel more than anything else but it was a true shark nonetheless.  It also sported a long spike growing up from the base of its skull which may have been a defensive weapon against larger predators.  It is this spike that gives the shark its name which translates to "Vertical Spike".  There are actually several kinds of living sharks that have spikes, too but all of theirs grow from the base of the dorsal fin, not the skull. Orthacanthus's teeth grew in pairs or "twins".  This means that there were two pointy teeth coming out of one root.

Orthacanthus fossil.

When alive Orthacanthus likely was an opportunistic predator and probably hunted the many kinds of other fish as well as amphibians it shared its shallow freshwater environment with.  It may also have periodically encountered the giant mammal-like reptile, Dimetrodon, which could have preyed upon it.

Orthacanthus tooth that shows the twin...wait no sorry this one has three.  The triplet style tooth.  Sharks always go above and beyond when it comes to teeth evolution.

That's all for this week!  Remember, just because Shark Week is done doesn't mean you can't still be shark crazy the rest of the year!  As always feel free to comment below and on facebook!

References

D. Heyler and C. Poplin. 1989. Systematics and relationships among the Xenacanthiformes (Pisces, Chondrichthyes) in the light of Carboniferous and Permian French materal. Acta Musei Reginaehradecensis S. A.: Scientiae Naturales 22:69-78

Thursday, August 8, 2013

Living Fossil: Shark

Its shark week.  Lets talk about sharks!

I feel like in some ways sharks have become the poster child for the "living fossil" concept.  When teaching a group of children at my job at the zoo and the subject of prehistoric animals pops up at least one kid will raise a hand and mention sharks to me without fail.  Although not as old as some other animals I have spoken of before, sharks are indeed a highly successful animal that has been around on the planet long before the first dinosaurs.  Some of the oldest shark fossils exist from about 400 million years ago during the Devonian Period.  These first sharks are not as large and imposing as some of the ones we are familiar with today.  In fact, scientists speculate they would have more closely resembled their relatives, the rays in some ways.


Fossil of Doliodus promlematicus, the oldest known shark. 

From that point on sharks never stopped flourishing.  They diversified into so many different forms, some of which we are familiar with today and others that we may not even recognize as being an actual shark.  Stethacanthus was an extinct genus of shark that lived about 360 million years ago during the Carboniforous period.  It more or less resembled some modern sharks despite a few subtle differences including differences in tail fluke proportions but what really sets it apart is the fact that it had a strange platform growing out of its back lined with bony teeth called denticles.  Denticles are essentially teeth that cover a shark's entire body (all sharks are covered with them) but they were exceptionally large on the top of Stethacanthus.  

Stethacanthus fossil.

Another interesting kind of shark that existed slightly later in during the Permian era, almost 300 million years ago (not long after the first dinosaurs), called the Xenacanthids resembled an eel with because of its body shape.  These sharks commonly sported spikes on their dorsal sides and existed in fresh water.

Xenacanthid fossil.

By the time the Cretaceous rolled around some of the sharks wouldn't have been that different looking from the sharks we are familiar with today despite being a different family.  One such shark was called Cretoxyrhina which could grow to about twenty feet long (same size as a really big modern Great White).  Despite their impressive size, these sharks wouldn't have been the top predators of their environment and probably fell prey to giant prehistoric marine lizards, called Mosasaurs, which existed at that time as well.  

Cretoxyrhina fossil.

Oh yeah and then millions of years later, closer in time to the present day, there was this one species of modern-style shark called Charcharodon megalodon that got pretty big.  Its extinct now though, despite what a fictional documentary aired on the Discovery Channel may have misled some people to believe.

I made another meme!

No, seriously there is zero chance megalodons are alive still.  No,they couldn't be hiding in the dark parts of the ocean we haven't explored yet.  If they were still out there they probably would be migrating around the world, eating whales and junk all near the surface of the water so...yeah somebody would have seen them.  Sorry.

megalodon life reconstruction by Christopher DiPiazza.

So what is it about sharks that made them stand the test of time since the Devonian?  Well. they certainly have a number of unique characteristics like denticles for scales and skeletons almost entirely made of cartilage (stuff inside our noses and ears) which aids in them being light and flexible.  Some sharks can even thermo-regulate their own bodies thanks to muscle friction despite being cold-blooded animals.  I really think they are successful because they managed to diversify into so many different forms and fill so many aquatic niches early on though.  Keep in mind many sharks have gone extinct over the millennia but since they were so diverse, there were always successful species to survive when others died.  Lets hope they continue to flourish to fascinate us for years to come! 

Sit tight.  I'll have a prehistoric shark in store for you to check out this Sunday as a farewell to shark week.  Remember, just because the official week is coming to an end doesn't mean you should stop loving and learning about sharks!

References

Bruner, J. C. (Sept.-Oct. 1997). "The Megatooth shark, Carcharodon megalodon: Rough toothed, huge toothed". Mundo Marino Revista Internacional de Vida (non-refereed) (Marina) 5: 6–11

Egerton, Philip De Malpas Grey. "XLII.—Pleuracanthus, DiplodusXenacanthus,Xenacanthus Decheni ()." Journal of Natural History Series 2 20.120 (1857): 423-24. Print.

Everhart, Mike. "A GIANT GINSU SHARK (Cretoxyrhina mantelli Agassiz) From Late CRETACEOUS Chalk of KANSAS"

Haven, Kendall (1997). 100 Greatest Science Discoveries of All Time. Libraries Unlimited. pp. 25–26. ISBN 1-59158-265-2.

Miller, Randall F., Richard Cloutier, and Susan Turner. "The Oldest Articulated Chondrichthyan from the Early Devonian Period." Nature 425.6957 (2003): 501-04. Print.

Pimiento, Catalina; Dana J. Ehret, Bruce J. MacFadden, and Gordon Hubbell (May 10, 2010). Stepanova, Anna. ed. "Ancient Nursery Area for the Extinct Giant Shark Megalodon from the Miocene of Panama"


Thursday, August 1, 2013

Field Work in New Mexico 2013

Finally I am getting around to sharing with you Gary and I's trip to New Mexico a few weeks ago!  My apologies for the delay but we both needed to take time after getting back to organize ourselves in addition to doing our regular jobs.

Tucumcari, New Mexico, is about an hour and a half long drive from Amarillo, Texas, with nothing but plains and desert on either side of the road. Then you find the town itself which centers around one road (Rt 66) consisting of a few miles of buildings, about half of which are abandoned.  It's interesting because this place was probably booming during the 50s.





No wonder this one was abandoned.  Its hard to avoid getting roasted just by standing outside.

Oh did I mention it's hot?  REALLY hot.  Don't get me wrong we have our share of heat waves in New Jersey but out there, not only was it brutally hot, but also extremely dry which was something I wasn't used to.  Despite the heat the land is really beautiful.


Hi cows!


Hundreds of windmills which is the main source of power there.


If you know me and my interests at all you would also know that I make it a point to at least find a few reptiles in a place like this.  In my short eight day stay I only was able to see three species of lizard, two of which I got pictures of.

A Whiptail Lizard.  Possibly Cnemidophorus marmoratus?

Southern Fence Lizard, Sceloporus cowlesi

 There was also no shortage of Invertebrates.

American Cockroach

A dead solifugae I found in the trash at the museum lab.  Yes, I garbage pick for dead arachnids.



I also was lucky to see some Mule Deer, a Pronghorn Antelope, and a Swift Fox off the road.  Unfortunately I wasn't fast enough with my camera.  Dang mammals.

The Mesalands Dinosaur Museum, which we were working with for this trip, is awesome and had many great specimens both on display and hidden away in its lab.  Here are just a few of their exhibits.

Gary checks out some fossils that he collected and prepped in years past that are now on display.

There are few things sexier than gazing upon a man's face through the other side of a Triceratops naris hole.

Torvosaurus skeletal mount.

Look out for that Acrocanthosaurus model!

Now that we have the lay of the land lets get familiar with the actual work.  The site we were working on is called the Redonda Formation, and is from the late Triassic Period, about 200 million years ago.  It is from the same time as the nearby, more famous, Ghost Ranch site where the hundreds of Coelophysis skeletons were unearthed.  The environment 200 million years ago wasn't an arid desert but a network of streams and lakes thick with horsetails and ferns.  The reason why this site has so many animal remains is because animals would come to a river (perhaps the same one from Ghost Ranch) to drink during the dry season and die of thirst when there was no water.  Then their remains would have washed downstream when the water did arrive and eventually settle at the bottom of a lake.  That lake is now the site we were digging on.  Because of this there aren't any complete skeletons, just lots of random bones all densely packed in a relatively small area from a wide variety of different animals of that time.   Lets meet the animals they belonged to, shall we?

Redondasaurus

Life reconstruction by Christopher DiPiazza.

Redondasaurus was the most common animal we were finding.  It belongs to a now extinct group of reptiles called the phytosaurs.  Phytosaurs looked a lot like modern crocodiles but this resemblance was the result of convergent evolution and filling a similar niche, not an actual close family relationship.  In fact, when phytosaurs were alive, the true crocodilians were actually small land animals and didn't start to evolve into what we know them to be today until after the phytosaurs went extinct at the end of the Triassic.  One easy way to tell the difference between a phytosaur and a crocodilian is the nostril placement.  Crocodilians have their nostrils on the tip of their snouts while phytosaur nostrils are farther back, closer to their eyes.  Phytosaurs also had a variety of different kinds of teeth in their mouths which is unusual for a reptile (some are long and cone-shaped for snagging prey and some are flattened and blade-like for slicing meat).  Some of the Redondasaurus skulls that were being collected were over four feet in length.  The biggest adults could have grown to measure over twenty feet long from snout to tail, making them the most formidable predators of their time.  There were plenty of bones from their bodies as well as their teeth to be found. 

Typothorax

Life reconstruction by Christopher DiPiazza.

Typothorax belongs to another now extinct group of reptiles called the aetosaurs.  They were likely mostly plant eaters, had odd upturned snouts possibly for rooting in the earth, and sported wide bony armor plates down their backs and even on their bellies and legs.  They look like armadillos, turtles, and ankylosaurs, but were more closely related to crocodiles.  If you remember I actually reviewed another aetosaur, Desmatosuchus, for a "Prehistoric Animal of the Week" while I was in New Mexico. Although many Typothorax bones were found from this site, the most common fossils from them were their rectangle-shaped armor plates.


Coelophysis

Life reconstruction by Christopher DiPiazza.

Coelophysis was the only actual dinosaur known from this area.  It was a bird-like meat-eater and only measured about nine feet long (most of that length would be skinny neck and tail).  Keep in mind that during the Triassic, dinosaurs weren't the dominant land animals yet and still were competing with a lot of other kinds of large reptiles.  It wouldn't be until later, in the early Jurassic, that dinosaurs would evolve into larger, what some consider more familiar, forms.  Coelophysis bones are hollow (like a bird's) and are therefore very easy to accidentally break in the field if one isn't careful.  They are also much smaller than the bones from adult phytosaurs and aetosaurs.

Shuvosaurus


Reconstruction by Christopher DiPiazza.

 The plant-eating Shuvosaurus was a very interesting little reptile.  At first glance it looks exactly like a dinosaur.  It walked upright on its hind legs, had a long neck, a beak, and it even had hollow bones!  However, because of the shape of its hips and the fact that it had a rotating ankle instead of just a simple hinge ankle, it was actually not a dinosaur, but a closer relative of crocodiles that evolved to look just like an ornithomimid dinosaur. (which didn't actually evolve until millions of years later)  It is unclear if the bones from this site are actually from Shuvosaurus or from a possible new kind within the same group.

You may notice that all of the animals I mentioned are reptiles, specifically archosaurs.  Archosaur is the clade of reptiles that includes modern crocodilans and birds.  Dinosaurs are the most famous members, but during the Triassic, the world was full of all different kinds!  I consider the Triassic the age of archosaur diversity.  Another thing you may notice about the Triassic is that several of the archosaur forms are evolving very similar body plans.  Dinosaurs like Coelophysis, poposauroids, and the rauisuchians (family that Postosuchus belongs to) all walked fully upright on their hind limbs and had hollow bones.  In fact, it was probably getting to the point where a lot of these archosaurs were competing with one another because they were becoming so similar.  Then a little after 200 million years ago a huge extinction hit the planet and wiped out a LOT of land animals, including the rauisuchians, shuvosaurids, aetosaurs, and the phytosaurs.  That's a lot of dead archosaurs!  For some reason only the dinosuars, crocodilians, and pterosaurs slipped through.  (note how the survivors are not similar to one another)  One could say that the reptilian bipedal style was quite popular back then but the dinosaurs wore it best!

This is basically the end of the Triassic as far as archosaurs go.

So we went out there at the buttcrack of dawn to start digging.  We all piled into a monster truck from the 1980s and drove over terrain that we probably shouldn't have but somehow we survived every morning.

We are happy in this photo because we just realized we weren't going to fall off a cliff and die.

Luckily where we were working is a known fossil spot and finding bones wasn't hard at all.  In fact while we were digging out certain bones we had found, we would accidentally find more!  In the movies they always show paleontologists actors effortlessly brushing off a layer of dust to reveal a perfect specimen...yeah not happening here.  We were using chisels and hammers to break off chunks of rock to get to pieces of skeletons.

Our mentor, Dr. Axel Hungerbuehler, is basically telling us not to do anything idiotic while out in the desert, hours away from civilization.

That white thing is a Coelophysis vertebrae.

Luckily Gary and I both found notable specimens from Redondasaurus.  Gary found a huge rib and I almost demolished excavated a hip.   In addition, several Coelophyis and shuvosaurid bones were found as well as a HUGE Typothorax armor plate.


 Another common misconception about fossil hunting is that all the bones are excavated and cleaned off perfectly out in the field.  In reality doing that is a bad idea because it would be too easy to damage the fossils.  Instead we break out the chunk of rock that the fossil is in and wrap it up in plaster to protect it.

I make wide hats, purple gloves, and sunburn sexy.

Gary likes to go out and get plastered.  He also gets wet plaster on his hands while working with fossils.

Once the specimen is back at the lab we do what is called prep work.  This involves very carefully separating the fossil from the rock.  We use a variety of tools to do this depending on the situation.

There are three small bones in those three giant chunks of rock.  Gary looks excited because he knows he has to get them out with dental tools and wet Q-tips.

Here is a Redondasaurus tooth in the rock.
Finally got it out after a while of electric drilling.
After getting the last few bits of earth off with Q-tips it's ready to display!
 Also check out my dirty fingernail.  Ew.

So that is the short version of what went down in Tucumcari, New Mexico in  the summer of 2013!  Hopefully when we go next year we will find even more amazing discoveries!  Would you like to work with fossils?  What do you think would be more fun, field work or lab work?  We would love to hear your thoughts!


References

Chatterjee, S. (1991) An unusual toothless archosaur from the Triassic of Texas: the world's oldest ostrich dinosaur? Abstract, Journal of Vertebrate Paleontology, 8(3): 11A.

Cope, E.D. 1875. The geology of New Mexico. Philadelphia Academy of Natural Sciences Proceedings, pp. 263-267.

Hungerbühler A. 2002. The Late Triassic phytosaur Mystriosuchus westphali, with a revision of the genus. Palaeontology 45 (2): 377-418

Martz, J.W. 2002. The morphology and ontogeny of Typothorax coccinarum (Archosauria, Stagonolepididae) from the Upper Triassic of the American southwest. M.S. thesis, Geosciences, Texas Tech University, Lubbock, 279 pp.

Nesbitt, S. (2007). "The anatomy of Effigia okeeffeae (Archosauria, Suchia), theropod-like convergence, and the distribution of related taxa." Bulletin of the American Museum of Natural History, 302: 84 pp.

Nesbitt, Irmis and Parker (2007). A critical re-evaluation of the Late Triassic dinosaur taxa of North America. Journal of Palaeontology, 5(2): 209-243.

Rinehart, L. F., Lucas, S. G., Heckert, A. B., Spielmann, J. A., and Celesky, M. D., 2009, The paleobiology of Coelophysis bauri (Cope) from the Upper Triassic (Apachean) Whitaker quarry, New Mexico, with detailed analysis of a single quarry block: New Mexico Museum of Natural History & Science, a division of the Department of Cultural Affairs, Bulletin, 45, 260pp.