Friday, March 30, 2018

Prehistoric Beast of the Week Visits the Canadian Museum of Nature

This past winter my wife and I took a road trip up to Canada.  It was really cold.  I left my pillow in the car over night and in the morning it was frozen solid.  I mean it was a literal ice brick.  Anyway, part of our visit involved checking out the Canadian Museum of Nature in Ottowa, Ontario.  There were fossils.  It was awesome.  Let's look at some photos together!

So many Natural History Museums are in old, beautiful buildings with interesting architecture.  If you know me well, you'll know I have a penchant for gargoyles. (or grotesques as they're called if they're not the kind that barfs water when it rains.)  The Museum of Nature sported a stone Moose's face over each major doorway.  A charming welcome to set the mood for anyone coming in.


Because I am actually a large child, my wife knew the smartest thing to do was see the dinosaurs first, because otherwise I'd be really annoying and on edge until we did.  Fossil exhibit it was!

The Museum of Nature's dinosaur hall is jam packed with specimens for the space that it provides.  The focal point of the dinosaur room is a skeletal mount of the tyrannosaurid, Daspletosaurus.  This museum does not have a T. rex on display.  I'm actually cool with that.  It's refreshing to see other, less widely known, meat-eaters get center stage sometimes.  The Daspletosaurus greets you as soon as you walk in the door with wide jaws.  A good intro of what is to come.



Another big theropod in this room that I was really happy to see was Carnotaurus.  This was actually the first proper Carnotaurus skeleton I'd ever seen in person. (Before this I had only seen the one in Disney World, which has an inaccurate skull.)



The Museum of Nature has a cool little section acknowledging feathered dinosaurs and the connection to modern birds.  This features a relief specimen of the ornithomimid, Dromiciomimus, a cast of Sinosauropteryx, which preserved feathers visible to the naked eye, and a 3D life reconstruction of Sinornithosaurus, which I believe I have seen on television and/or magazines before.

Dromiciomimus. (Can't not say that in Strong Bad's voice.)
Sinosauropteryx  cast.  Note the visible banded feathers on the tail.
Sinornithosaurus model with real feathers. 

The Canadian Museum of Nature is particularly awesome if you are a ceratopsian fan, like me.  They devoted a LOT of space to a myriad of genera from the horns and frills clade.  The most impressive, perhaps, is the relatively recently discovered ceratopsian, Spiclypeus, a skull of which is on display in the corner.  Paleontologists from the Canadian Museum of Nature helped describe and name this dinosaur, which had a unique frill ornamentation, and was discovered having had an infected, arthritic forelimb when it died.  The actual fossils of Spiclypeus are also in the Museum of Nature's collection.

The Spiclypeus skull was hard to get a decent photo of because it was behind glass and right next to a sunny window.

Other ceratopsians on display in this hall include Triceratops, Styracosaurus, Vagaceratops (mounted skull and articulated skeleton as it was found), Anchiceratops, and two Leptoceratops.

Styracosaurus skeleton.  Different specimen from the one I'm used to seeing in New York.
Vagaceratops skull.
Leptoceratops skeletons.

As I was leaving the hall of dinosaur fossils, I was pleasantly surprised to stumble right into the middle of an entire reconstructed scene from the late Cretaceous!  This walk-through features life-size, beautifully detailed models of a family of Vagaceratops, a nesting troodontid, and two Daspletosaurus.  This sections also makes for great photo opportunities since the Daspletosaurus totally look like they're smiling.

Troodontid with eggs.
Adult Vagaceratops photo op
Baby Vagaceratops.  Also look at how the feet are muddy, really driving home that they're part of the environment.  I've seen lots of life-size dinosaur models that appear to just be plopped down.
Daspletosaurus singing.

As any good paleoartist who also works with living reptiles would, I made a point to check out the Daspletosaurus' cloaca.   The model's was a vertical opening, like that of a crocdilian, not horizontal like that of a lizard...in case you were wondering.  You're welcome.

The cloaca.  Such a magical body part.  Poop, pee, and sex all from the same hole!
I thought it was cool how the scales on the bottom of the pubis were larger than the other scales on the underside.  Implying that this surface, armed with larger scales, was more resistant to the wear of being sat on when the animal was resting.
Dinosaur scene from the balcony.

After the dinosaurs, we were led into another floor that featured prehistoric animals from the cenozoic.  The focal point of this exhibit was another 3D life reconstruction of a family of Megacerops, as well as a Dinictis and Archeotherium.  The Megacerops were life-like, possessing super wrinkly skin.  I like how the artist made a point not to simply modify the look of a modern rhino for them, since they weren't as closely related to rhinos as one might think, despite  their appearence.

I was always interested at how far forward the eyes were on this animal.
Megacerops skeletal mounts across from the life models.

The Archaeotherium looks to be based off the modern Red River Pig, color wise.  It's teeth are all fully visible and not covered by any sort of soft tissue that might be expected for a mammal, making it that much more terrifying.

Mammals are scary.

I also appreciated the skeletons of prehistoric whales that were on display, showing the known fossil history of their evolution into the modern whales we know today.

Ambulocetus, one of the prehistoric whales that could walk on land was featured.

There were plenty more fossils to see on display at the Canadian Museum of Nature that I did not include.  That being said if you're ever in the area, I encourage you to go visit and see for yourself!  I will leave you with another one of its amazing exhibits that was not prehistoric, but just as fascinating. They had an almost complete, real Blue Whale skeleton!  I am familiar with the 3D life-size model of this species on display at the American Museum of Natural History in New York, but it was just as awesome seeing the real bones of this incredible mammal so close.  I love how the skeleton was at visitor level, not suspended from the ceiling, so we could get a really good look at it from the sides, which is not something I'm used to seeing in whale exhibits.

Almost complete  REAL blue whale skeleton.  Wife for scale.

Tuesday, March 20, 2018

Jinyunpelta: Beast of the Week

This week we will be checking out a newly discovered dinosaur that gives us interesting insight on the evolution of the armored ankylosaurids.  Check out Jinyunpelta sinensis!

Jinyunpelta was a plant-eating dinosaur that lived in what is now China during the Cretaceous period, between 106 and 96 million years ago.  The genus name translates to "Jinyun Shield" in reference to the part of China its bones were unearthed in.  Jinyunpelta was a member of the ankylosaurid family, charcterized by having bony armor  and a bony tail club.  More famous members of this family are the later Euoplocephalus and Ankylosaurus.


Life reconstruction of Jinyunpelta in watercolors by Christopher DiPiazza

Jinyunpelta is currently the oldest example of an ankylosaur that had a tail club.  That being said, its tail club is actually just as developed as much later members of its family.  The club, itself, was somewhat hexagonal when viewed from above, and widens towards the tip.  The tail vertebrae just behind the club are stiffened by bony rods, which would have added extra support in life.   The fact that Jinunpelta's club is so advanced tells us that ankylosaurs evolved tail clubs much earlier than the the time of Jinyunpelta.  So far no intermediate, smaller, less fortified tail club has ever been found on an older dinosaur.  The purpose of the tail club, as is the case with all ankylosaurids, is somewhat of a mystery.  However, it would have made for an effective weapon, by swinging it against the legs of predatory dinosaurs, or possibly even at the heads or flanks of members of the same species if they practiced any sort of intraspecies combat for dominance.

Jinyunpelta's tail club.  Image from Zheng's 2018 paper.

Jinyunpelta's skull was discovered, luckily.  Like all ankylosaurids, it had a flat beak, which was a bit more narrow than the beaks of known later ankylosaurids, but wider than the beaks of earlier armored dinosaurs.  The back of Jinyunpelta's mouth housed small teeth ideal for shredding plants.  Jinyunpelta would have had bony armor on the top of its head, and short horns over each eye, and growing from its cheek bones. (called jugals)

Jinyunpelta's skull.  Image from Zheng's 2018 paper.

Jintunpelta is an important scientific discovery because it proves that heavily armored, club-tailed ankylosaurs developed much earlier in history than previously thought.  This not only gives us answers, but also brings up more questions.  What were the environmental pressures causing these features to pop up at that time?  Maybe one day we'll find out.

References

Wenjie Zheng; Xingsheng Jin; Yoichi Azuma; Qiongying Wang; Kazunori Miyata; Xing Xu (2018). "The most basal ankylosaurine dinosaur from the Albian–Cenomanian of China, with implications for the evolution of the tail club". Scientific Reports8: Article number 3711.

Tuesday, March 13, 2018

Shringasaurus: Beast of the Week

Today we will be looking at a relatively recently discovered creature that was utilizing adaptations famous in different groups of dinosaurs...but wasn't a dinosaur.  Check out Shringasaurus!

Shringasaurus was a plant-eating archosauromorph reptile that lived in what is now India, during the Middle Triassic period, between 247 and 242 million years ago.  It measured a little over ten feet long from snout to tail and would have walked on four short, but robust limbs when alive.  The genus name translates to "Horned Reptile" because this animal possessed two, forward-curving horns on the top of its head.

Male Shringasaurus basking.  If I told you I wasn't a little inspired by Chuckwallas while painting this...I'd be lying.
 
Shringasaurus belonged to an interesting group of prehistoric reptiles, called allokotosauria.  These early archosauromorphs are characterized by having proportionally small skulls, semi-sprawling quadrupedal posture, and teeth and jaws that suggest they were herbivores in life.  During the middle Triassic, when many of these animals were alive, plant-eating animals are so far relatively rare on the fossil record.  So the more fossils that are discovered from these interesting creatures, the more we can paint an accurate picture of their environment!

Shringasaurus has a number of unique characteristics that set it apart as a beautifully unique animal.  Most notable are those horns.  Lots of reptiles have horns, but few groups of reptiles have forward-curved horns growing over the eyes.  Ceratopsians, the successful group of dinosaurs that includes Triceratops, are the most notable. Many species of modern chameleons also have horns like this.  Shringasaurus seems to have convergntly evolved similar horns, being only distantly related to both of these groups.  The real purpose for evolving these horns is somewhat of a mystery.  But there are clues!  Shringasaurus is known in the fossil record from several individuals.  Among these are smaller, younger individuals, that show smaller horns.  This means that the baby Shringasaurus started off with small, or perhaps no horns, and did not develop them until later in life, probably when they were sexually mature.  This supports the idea that the horns were some kind of an intraspecies display.  Further, there is one individual Shringasaurus skull that had no horns, but was otherwise the same size as other Shringasaurus skulls that had horns.  This strongly points to Shringasaurus having been sexually dimorphic, when the males and females are visibly different.  It is highly possible that Shringasaurus males used their horns to visually intimidate each other, maybe incorporating some kind of "dance" like many modern reptiles will do today, like bobbing their heads around to compete for mating rights.  They may have even used their horns to physically compete with each other, like shoving, or jousting, which is also observable in modern horned animals.

Graphic from Sengupta's 2017 paper describing Shringasaurus.  This image is showing a comparison between Shringasaurus' skull (top left) and the skull of the convergently evolved Arrhinoceratops (top right).  Below, letters d-g and h-k, show the  top and side views of the skulls from various Shringasaurus individuals.  Note how specimen g/k has no horns but is otherwise the same size as specimen f/j.

Another cool characteristic about Shringasaurus is its nostril holes.  They were connected, forming one hole, instead of two, in the front of the snout.  This kind of nose hole opening is not really known in reptiles until Shringasaurus, but is something seen in modern mammals.  Shringasaurus, for whatever reason convergently evolved an external nasal passage more similar to those of mammals from millions of years later!

Shringasaurus had small, leaf-shaped teeth in its mouth, probably for eating plants.  It also had a proportionally small head at the end of a very long neck.  This long neck is often compared to those of sauropod dinosaurs, but it reminds me a lot of Galapagos Tortoise necks too.  Shringasaurus probably used this neck for the same reasons sauropods and tortoises do, too, to help it reach more leaves to eat without moving its body.  Plants provide less energy to the consumer than meat, so plant-eating animals need to conserve as much energy as possible, being able to get as much food for the littlest amount of work is important.

References

Sengupta, S.; Ezcurra, M.D.; Bandyopadhyay, S. (2017). "A new horned and long-necked herbivorous stem-archosaur from the Middle Triassic of India". Scientific Reports. 7: 8366.

Sunday, March 4, 2018

Lesothosaurus: Beast of the Week

Lets look at an early dinosaur that gives us important insight on how dinosaurs evolved.  Check out Lesothosaurus diagnosticus!

Lesothosaurus was a small, probably omnivorous dinosaur that lived in what is now southern Africa during the early Jurassic Period, between 199 and 189 million years ago.  From snout to tail it measured a little over six feet long.  The genus name translates to "Lesetho Lizard" in reference to Lesotho, the country in Africa in which the first fossils of this dinosaur were found.

Lesothosaurus life reconstruction.  The hair-like feathers are entirely speculative.  However, preserved feathers have been found in other basal onrnithischian dinosaurs that fossilized under different conditions.

Lesothosaurus was originally considered a very early ornithopod dinosaur.  However, as time has passed and more fossils have been found, it has become more likely that this little dinosaur was something even more basal, predating not just ornithopods, but all ornithischian dinosaurs, including the armored thyreophorans (stegosaurs and ankylosaurs) and the horned marginocephalians (ceratopsians and pachycephalosaurs)

Lesothosaururs had interesting dentition that has led paleontologists to believe it was an omnivore in life.  In the front of the jaws it would have had a small beak, probably ideal for picking at leaves to eat.  The jaws, themselves, had mostly small, leaf-shaped teeth that were probably for cutting up plants, but it also had long, pointed teeth growing from the front of its top jaw.  These long teeth may have been an adaptation to help strip leaves off stems and branches, but they also could have been effective at processing animal-based food.  When paleontologists compared the teeth of Lesothosaurus to similarly-shaped teeth of other dinosaurs that were more primarily plant-eaters, Lesothosaurus showed notable less ware on its teeth.  Since processing plants is tougher on teeth than meat, this suggested that it was not eating as much plants as these other dinosaurs, and likely was a meat-eater, too.  Lesothosaurus probably wasn't going after large prey, since its teeth weren't blade-like for shearing off chunks of flesh from carcasses, like those of most primarily meat-eating dinosaurs, but it very well could have gone after small prey, like invertebrates, or any other creature that could be eaten in one or two bites.

Lower jaw of Lesothosaurus showing the teeth that were likely best ad processing plants.  Image from Sciscio's 2017 paper, referenced below.


Lesothosaurus had proportionally very long legs and a long tail that was slightly stiffened in life.  This means that it was a fast and agile runner when alive.  Its primary defense against predators of its time was probably to run away given its anatomy.

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

References

Barrett, P. M., Butler, R. J., Yates, A. M., Baron, M. G., & Choiniere, J. N. (2016). New specimens of the basal ornithischian dinosaur Lesothosaurus diagnosticus Galton, 1978 from the Early Jurassic of South Africa.

Butler, Richard J.; Upchurch, Paul; Norman, David B. (2008). "The phylogeny of the ornithischian dinosaurs". Journal of Systematic Palaeontology. 6 (1): 1–40.

Butler, R.J. (2005). "The 'fabrosaurid' ornithischian dinosaurs of the Upper Elliot Formation (Lower Jurassic) of South Africa and Lesotho". Zoological Journal of the Linnean Society. 145 (2): 175–218.

Matthew G. Baron; David B. Norman; Paul M. Barrett (2016). "Postcranial anatomy of Lesothosaurus diagnosticus (Dinosauria: Ornithischia) from the Lower Jurassic of southern Africa: implications for basal ornithischian taxonomy and systematics". Zoological Journal of the Linnean Society. in press.

Matthew G. Baron; David B. Norman; Paul M. Barrett (2016). "Postcranial anatomy of Lesothosaurus diagnosticus (Dinosauria: Ornithischia) from the Lower Jurassic of southern Africa: implications for basal ornithischian taxonomy and systematics". Zoological Journal of the Linnean Society. in press.

Sciscio L, Knoll F, Bordy EM, de Kock MO, Redelstorff R. (2017). Digital reconstruction of the mandible of an adult Lesothosaurus diagnosticus with insight into the tooth replacement process and diet. PeerJ, 5:

Saturday, March 3, 2018

Interview with Paleontologist: Jason Poole


Jason C. Poole is a professor at Drexel University and the Dinosaur Hall Coordinator at the Academy of Natural Sciences of Drexel University. Jason has excavated dinosaurs on three continents, Africa, South and North America. Paralititan, Dreadnoughtus and Suuwassea are three dinosaurs worked on by Poole which are new to science, two of which are super massive titanosaurs. Jason can often be
found in the Academy of Natural Sciences Dinosaur Hall Fossil Lab preparing newly found fossils which will spend the rest of their afterlife in museum collections. Mr. Poole is also a Paleo Artist who has published in National Geographic and whose art work appears in many museum and private collections.



Question 1: Let’s start from the beginning.  What was your earliest sign of interest in paleontology that you can remember?   

JP: I collected modern bones and fossils as a kid.

Question 2: Did you have any professionals or family members who served as role models when you were younger?  Do you still have any now? 

JP: My folks loved to be outside when we had free time so I got my love of that from them. But I have to say that Dr. Peter Dodson was and still is a huge reason that I am still doing what I do.

Question 3: Was there anything you did or learned as you were on your way to your current career that you feel got you to where you are?  By this I mean any sort of field experience, a class, networking with the right people, or possibly something different or all three? 

JP: I surrounded myself with people who love science and the outdoors.

Question 4: Is the field of paleontology different now than from when you started as far as you can tell?  What would your advice be to anyone trying to make a career in paleontology (or science in general for that matter) now?  

JP: Now as always I recommend that students who want to become paleontologists become obsessed with science in general and new trends in what new tech can help to explain.

Question 5: What was or is your favorite project so far?  Would you be able to tell us about some of your current projects? 

JP: I love working on Jurassic dinosaurs with the Bighorn Basin Paleontology Institute and the Academy of Natural Sciences! This cooperation gives me the opportunity to educate about paleo in the field to students and volunteers in one of the most beautiful places in the world.   

Question 6: You have traveled to a lot of interesting places digging for dinosaurs.  Do you have a favorite destination when it comes to fossils?  Why? 

JP: I love Montana. My first dinosaur was from there.

Question 7: A popular image of paleontologists is that they are constantly out in the field digging up fossils, which is true to an extent.  What people don’t realize sometimes is that a lot of paleontology work is conducted in a lab as well.  In your experience, how much of your projects (in general) take place in the field, and how much are in the lab?  

JP: My job in Philly is as a preparator and teacher. So 10 months of the year are spent in lab.

Question 8: When it comes to your art, how often are you able to utilize it for paleontology?  

JP: Every day.  It is part of the way I communicate and take notes.

Question 9: What is your favorite medium to use when creating art?  Why?  

JP: Ball Point Pen. It travels well and gives a great line for sketching. 

Jason's reconstruction of the sauropod, Suuwassea.
Question 10: Do you ever get criticized on any of your work? How do you handle it?

JP: I am constantly criticized buy people, the harshest remarks are my own. It is how we grow as artists. Constant pushing and tweaking of our craft due to feedback from people and our own mistakes. I think I handle it well… I have not killed anyone yet.   

Question 11: One of my pet peeves is when people assume paleontology doesn’t really do any real good in the grand scheme of things and is just a “for fun” science.  Do you think paleontology has a bigger part to than this?  How?  

JP: You cannot know the future so you better know the past if you are going to make any informed plans for the future. Evolution and understanding how species react to natural pressures exerted by a changing world is key especially now when we should be looking to science to direct thinking about our future.

Question 12: Who was the first paleontologist you met?  How was that interaction?  

JP: Bill Gallagher. He is a great guy!

Question 13: What is your favorite prehistoric animal?  Was it different when you were younger?  

JP: Ceratosaurus. Nope.

Ceratosaurus skeleton on display at the National Museum in Washington, D.C.
Question 14: If you could use a time machine to go back and pick only one prehistoric animal to bring back from history and observe alive and in person, which would it be and why?  

JP: T. rex. T. rex gets so much attention and we think we know tones about it. I would love to see how far off we might be. I think it would be a great test of how far off we should expect to be off on other animals. Here is the rub though, When you take an animal out of its ecosystem or habitat you will not know how it naturally behaves.

Question 15: Which is your favorite museum? Why? The Academy of Natural Sciences of Drexel U. in Philadelphia.  

JP: We started this paleo thing in the Americas and we are still going. I am most excited for our future as a public museum and a research institution! Come see why.  

Question 16: What hobbies do you have?  (Don’t have to be paleo-related.)  

JP: Not a lot of time for hobbies. Love to build model kits and skateboard. Family fills most of the free time now.