Tuesday, December 30, 2014

Spinosaurus: Beast of the Week

2014 was a good year for paleontology.  We saw many new species published, like Changyuraptor, Mercuriceratops, Rhinorex, Dreadnaughtus and Aquilops.  We also witnessed discoveries that completely changed the way we look at already-known species such as Deinocheirus or...the beast I'm about to talk to you about right now.  Make way (lots of room...back up more...keep going...keep going...backbackbackback) for the mighty Spinosaurus Aegyptiacus!  Out of all the discoveries in paleontology made this year, I feel that the new information unearthed about Spinosaurus is the most dramatic.

Spinosaurus was a meat-eating dinosaur that lived in what is now Africa, including Egypt and Morocco, during the late Cretaceous Period, about 97 million years ago.  It was a massive animal, measuring about forty nine feet long from snout to tail as an adult, making it the largest meat-eating dinosaur known to science.  The genus name, Spinosaurus, translates to "Spined lizard/reptile" in reference to the extremely long neural arches on it's back vertebrae. (We have neural arches too, just smaller.  If you run your finger down your spine, you can feel them.) Some of these spines were almost six feet tall, giving the animal a very striking profile in life.

Life reconstruction of a Spinosaurus aegyptiacus ambush hunting a crocodile while underwater by Christopher DiPiazza.

Spinosaurus has one of the richest histories behind its discovery.  It was first unearthed back in 1912 and published in 1915 by German Paleontologist, Ernst Stromer.  Back then all he had to work with was very fragmented remains including a part of a lower jaw, some vertebrae, and a few ribs, not enough to know for sure what the whole animal looked like, but certainly enough to tell it was something new and exciting.  For decades the remains of Spinosaurus remained in a museum in Munich, Germany, on display.  During World War II, allied forces bombed the area where this museum was.  Luckily some small fossils, including the first discovered Pterodactylus, and arguably the most valuable fossil in the world, Archaeopteryx, were able to be evacuated ahead of time but the poor bones of Spinosaurus were destroyed.  For decades the world had no real Spinosaurus fossils to study beyond the photographs and drawings left behind of the originals and small bits and pieces that didn't give any real new information found here and there every so often.  In fact, Spinosaurus teeth are actually quite common and are frequently sold in fossil and mineral stores.

Illustration of the original fossils found of Spinosaurus from Ernst Stromer's 1915 publication.  You can see three of the vertebrae with the tall neural arches on the left and the lower jaw piece on the lower right.  The straight, cone-shaped teeth are illustrated larger above the jaw.

It wasn't until the year 2005 that another big piece of Spinosaurus was found.  Italian Scientists digging in Morocco found pieces of a Spinosaurus skull, including most of the snout and the nostrils.  This showed that Spinosaurus had a much narrower snout than previously thought.  Then, this past year in 2014, paleontologist, Nizar Ibrahim, published a paper about even more material from this amazing animal, which included more of the spine and the hind legs that he and his team had uncovered in Morocco.  It was this discovery that changed Spinosaurus' image from unique to something that looks more at home in mythology. (Yes, even by dinosaur standards.)

Spinosaurus had many unique features about it that pretty much break all the rules of what we thought we knew about theropod dinosaurs.  We will start with the head and work our way back.  Spinosaurus belongs to a family of dinosaurs called spinosauridae (named after it, the first known member) which are all characterized by having very long, narrow snouts, similar to that of a crocodile.  In these snouts they all had straight, pointed teeth, and their nostrils were not at the tip of the snout, but higher up towards the middle.  These characteristics led scientists to believe that spinosaurids were adapted to hunting fish.  Their arms were powerful and possessed three fingers on each hand.  Digit one of each hand had an enormous, hooked claw on it, much larger than the other two.  This was probably another adaptation to hunting since hook-shaped weapons are common adaptations in predatory animals.

Spinosaurus skeletal mount on display at the National Geographic Museum.

As stated before, Spinosaurus had extremely long neural arches on its back that ould have been covered in skin and other living tissue when the dinosaur was alive, giving it a sail-like appearance in life.  This is not completely unlike the sail of the also famous mammal-like reptile (and totally not a dinosaur), Dimetrodon, which lived millions of years earlier.  Despite the similarities, these two animals are not directly related to each other and is just another beautiful example of convergent evolution.  The function of the sail on Spinosaurus is something nobody can quite agree on.  There are always those who will say an adaptation like that was for display within the species.  Others believe it was to help regulate the animal's body temperature, having possibly been rich in blood vessels in life and easier to heat up in the sun.  This is a good hypothesis especially if Spinosaurus was spending a lot of its time near or in the water to hunt.  Bodies of water always cool an area down and being in or near it can lower an animal's body temperature to the point where it needs to leave the area to warm up again.  Those that don't leave the water have special adaptations to help them stay warmer longer.  Think about ducks and geese (which produce their own heat, being endothermic) and how they have a layer down feathers against their bodies.  Also think about modern Marine Iguanas (cannot produce their own body heat as ectothermic) and how they can only stay in the ocean for a few minutes at a time until they need to haul out on shore to absorb more warmth from the sun.  A good way to experience this is going out on a boat during the summer, it may be hot on the land but trust me, you will want to bring a jacket if you are out on the water for a long while!  The sail on Spinosaurus may have been a way for it to increase its surface area to warm itself up in the sun as efficiently as possibly while still being able to hang out in places with lots of water for long periods of time.  The shape of Spinosaurus' sail has changed over the years with new discoveries.  The newest information about it suggests the sail was somewhat rectangular, with a shallow dip in the middle.

Finally we have the legs which is where this dinosaur gets really strange-looking. (That's right.  The strangest part is still coming.)  For decades nobody really knew what the legs looked like.  We just assumed they were the same as those of its close relatives like Suchomimus and Baryonyx, fellow spinosaurids which scientists had more complete skeletons of and were typical for theropods, long and powerful, supporting an obligatory bipedal posture.  The discovery that was published this year changed all that, however.  According to what was unearthed,  Spinosaurus had short legs...like really short legs.  So short that it would have had a rough time even standing on two legs.  Some scientists have even proposed Spinosaurus may have been a quadroped, possibly walking on its knuckles to keep its claws sharp.  (Keep in mind that up to this point all known theropod dinosaurs were obligatory bipeds.)  Right after this publication was released many people thought that perhaps the paleontologists suggesting these odd proportions had not considered maybe their new leg material was from a juvenile specimen and was not scaled up to the other already-known material which was from adults.  The problem with that argument is that the new leg material was found with other bones that were almost certainly all from the same individual, including some of the long spine vertebrae, which were big just like the other adult-sized material already on the fossil record from Spinosaurus.  The mighty Spinosaurus really did have the proportions close to that of a dachshund mythical Asian Dragon!

My sketch of how a Spinosaurus may have moved on land.  If the tail was heavy enough (and if it was a swimmer with a muscular tail anything like those of modern crocodilans, it may very well have been) it may have been able to pull off bipedal locomotion.

The new discoveries didn't end there.  Spinosaurus' feet were unique in that the toes were flatter and wider than what is typically seen in theropod dinosaurs, except for certain birds that have webbed toes for paddling like penguins and ducks, suggesting Spinosaurus had webbed toes as well.   Spinosaurus' bones were also not hollow like those of most other theropods.  Instead they were dense and solid.  Penguins are another kind of theropod with solid bones so that they can swim under water more easily.  These two amazing discoveries, combined with what we already knew about Spinosaurus' snout and teeth, lead us to believe that this dinosaur was specially adapted for a life in the water.  Even having short legs makes more sense.  Think of the legs of hippos and otters.  These are animals that, although pretty good at getting around on land, really move best when under the water.  Also, if Spinosaurus was under the water a lot, having a large sail on its back which may have been more often poking above the surface to soak up some warmth from the sun, it would have been able to help prevent its body from getting too cold.  All of these strange adaptations which confused scientists for many years all start to come together a little more with the help of just a few more new (yet strange) discoveries!

Spinosaurus running under the water like a boss...or a hippo.  I have my doubts if this dinosaur was actually good at swimming, through the water like a crocodile, but walking/running around under it, sure, given its anatomy.

Finally, if Spinosaurus was an aquatic dinosaur, it would also make more sense of what we know about its environment.  The areas that Spinosaurus bones have been discovered in have a lot of other fossils in them too, most notably lots of other species of meat-eating dinosaur, and also lots of aquatic creatures like fish, turtles, and crocodiles.  Before this year, it was assumed that Spinosaurus was so large because it was competing with other predatory dinosaurs, like the slightly smaller allosauroid, called Carcharadontosaurus, and various ceratosaurs.  Despite this, it still always seemed strange to have that many predators but not so many plant-eating dinosaurs in the community.  Now we know that Spinosaurus probably evolved in a completely different direction to avoid competition altogether.  It was more likely an aquatic predator, spending more of its time in the water hunting fish and other aquatic prey.  This way it wasn't occupying the same space, nor was it competing for the same food as its fellow theropods.  Since it was the only dinosaur to exploit such a unique niche, it could have evolved to be extremely large without any competition.

As you can now see, 2014 was a big year for Spinosaurus.  It holds many titles as a dinosaur.  Not only was it the largest known meat-eater, it was also the only known non-avian dinosaur to have actually been aquatic. That is all for this week!  Join us next year for more Prehistoric Animals of the Week!  As always feel free to comment below or on our facebook page

References

dal Sasso, C.; Maganuco, S.; Buffetaut, E.; Mendez, M.A. (2005). "New information on the skull of the enigmatic theropod Spinosaurus, with remarks on its sizes and affinities". Journal of Vertebrate Paleontology 25 (4): 888–896. doi:10.1671/0272-4634(2005)025[0888:NIOTSO]2.0.CO;2. ISSN 0272-4634.

Ibrahim, N.; Sereno, P. C.; Dal Sasso, C.; Maganuco, S.; Fabbri, M.; Martill, D. M.; Zouhri, S.; Myhrvold, N.; Iurino, D. A. (2014). "Semiaquatic adaptations in a giant predatory dinosaur". Science. doi:10.1126/science.1258750.

Smith, J.B.; Lamanna, M.C.; Mayr, H.; and Lacovara, K.J. (2006). "New information regarding the holotype of Spinosaurus aegyptiacus Stromer, 1915". Journal of Paleontology 80 (2): 400–406. doi:10.1666/0022-3360(2006)080[0400:NIRTHO]2.0.CO;2. ISSN 0022-3360.

Stromer, E. (1915). "Ergebnisse der Forschungsreisen Prof. E. Stromers in den Wüsten Ägyptens. II. Wirbeltier-Reste der Baharije-Stufe (unterstes Cenoman). 3. Das Original des Theropoden Spinosaurus aegyptiacus nov. gen., nov. spec". Abhandlungen der Königlich Bayerischen Akademie der Wissenschaften, Mathematisch-physikalische Klasse (in German) 28 (3): 1–32.

Sunday, December 21, 2014

Aquilops: Prehistoric Animal of the Week


Today we will be learning about a newly discovered kind of dinosaur that sets the record for oldest ceratopsian (beaks and frills) ever discovered in North America!  Check out Aquilops americanus!  

Aquilops was a plant-eating dinosaur that lived in what is now Montana, USA, during the Early Cretaceous Period, between 104 and 108 million years ago.  It was tiny, only two feet long from beak to tail, but was a very early member of the ceratopsian group of dinosaurs, which includes the very famous, Triceratops.  The genus name, Aquilops, translates to “eagle face” in reference to the dinosaur’s hooked beak.  The species name, americanus, is because it lived...in America.

Aquilops life reconstruction by Christopher DiPiazza.

 Even though Aquilopsis only known from a single skull, it is a very important find that provides a lot of information about dinosaur evolution.  Never before has a ceratopsian fossil as old as Aquilops been discovered in North America.  The next oldest in the continent is Zuniceratops, at 90 million years old.  Aquilops proves that ceratopsian dinosaurs migrated to North America from Asia (where Yinlong, the oldest known member of the group was found) earlier than previously thought.  

Skull of Aquilops americanus.  Photo provided by Andrew Farke.

Aquilops has a few interesting features about it physically.  Most noticeable is the small bump (called a boss) that appears at the front of its beak.  In life, when the beak was covered in a layer of keratin, there may have been a point there, like a horn, or maybe extended keeled edge to it.  The beak itself curved downwards and ended in a sharp point which may have aided the animal in selectively feeding on vegetation.  Inside its mouth, it had three long teeth coming from the top which may have helped the little fellow to strip soft leaves off of plants.  Some people hypothesize that ceratopsians like Aquilops may have been omnivorous as well, supplementing their diets with meat from time to time, possibly insects or carrion.  In the back of its mouth, Aquilops had rows of small teeth that appear to have been good for crushing plant material.  It also had proportionally huge, round eye sockets and when alive, may have been crepuscular, most active at dawn and dusk, or maybe even nocturnal, most active at night, to help avoid predation.  On the back of the skull Aquilops had a small frill and pointed jugal bones (cheek bones) on either side of its face behind the eyes.  It was probably able to walk on its hind legs or on all fours if it wanted to.  We can hypothesize this based on the limb proportions we see in other early ceratopids like Yinlong and Archaeoceratops.

That is all for this week!  Also special thanks to paleontologist, Andrew Farke, for lending his expert input on my painting and review of this amazing little dinosaur.  Stay tuned for next week when I review the last prehistoric animal of 2014! (It's going to be a big one.) If you have any requests for the upcoming beasties please do not hesitate to comment below or on our facebook page

References

 Farke, Andrew A.; Maxwell, W. Desmond; Cifelli, Richard L.; Wedel, Mathew J. (2014-12-10). "A Ceratopsian Dinosaur from the Lower Cretaceous of Western North America, and the Biogeography of Neoceratopsia". PLoS ONE 9 (12). doi:10.1371/journal.pone.0112055.

Monday, December 1, 2014

Pampaphoneus: Prehistoric Animal of the Week

This week, as requested by one of our fans on facebook, we will be looking at a truly intimidating carnivore that has distant ties with us humans.  Make way for Pampaphoneus biccaiPampaphoneus lived in what is now Brazil during the middle Permian Era, about 260 million years ago, tens of millions of years earlier than the first dinosaurs.  When alive, because of its teeth, scientists believe Pampaphoneus was a meat-eater, possibly hunting other reptiles it coexisted with.  Pampaphoneus is only known from one skull but by comparing its proportions to more complete relatives on the fossil record, its snout to tail length can be estimated somewhere between four and six feet long.  The name, Pampaphoneus, translates to "killer from the Pampas" in reference to the area of Brazil in which the fossil was discovered.

Life reconstruction of two Pampaphoneus getting up from a snooze by Christopher DiPiazza.

 Visually, Pampaphoneus is difficult to place compared to animals that are alive today.  It was clearly reptilian but it has some striking mammalian features as well, especially in its teeth.  This is because Pampaphoneus was a kind of dinocephalian.  Dinocephalians are considered "mammal-like reptiles" and illustrate one of the branches of the reptilian family tree that was on its way to becoming mammals.  These peculiar creatures came in a variety of sizes and shapes during the middle Permian.  Some ate plants, others ate meat, most had some sort of knobby protrusions on their skulls, and many of them had long teeth.  By human standards they were pretty ugly, not gonna lie.  Ugly in a beautifully fascinating way, though!  Sadly, dinocephalians never actually made it that far, however, having disappeared from the fossil record pretty abruptly around 260 million years ago, but the Permian Era was full of other mammal-like reptiles, which would eventually give rise to true mammals like us hundreds of millions of years later.  The very famous, Dimetrodon, is another kind of mammal-like reptile, but is not a dinocephalian.

Pampaphoneus biccai skull


Pampaphoneus is interesting because it is the only dinocephalian found in South America.  All other known dinocephalians are from either South Africa or Russia.  This tells us that during the Permian era, these mammal-like reptiles had to have had a way to disperse from continent to continent.  They were able to do this quite easily because back then, the seven continents we have now were actually joined to form one massive land mass, called Pangea.  Finding similar fossils on different continents helps scientists map out closely how the continents at one point were joined together and how long ago they separated.

That is all for this week!  Join us next time for another Prehistoric Animal of the Week!  As always feel free to comment below or on our facebook page

References

Angielczyk, K. D. (2009). "Dimetrodon is Not a Dinosaur: Using Tree Thinking to Understand the Ancient Relatives of Mammals and their Evolution". Evolution: Education and Outreach 2 (2): 257–271. doi:10.1007/s12052-009-0117-4.

Cisneros, J.C.; Abdala, F.; Atayman-Güven, S.; Rubidge, B.S.; Şengör, A.M.C.; Schultz, C.L. (2012). "Carnivorous dinocephalian from the Middle Permian of Brazil and tetrapod dispersal in Pangaea". Proceedings of the National Academy of Sciences of the United States of America 109 (5): 1584–1588. doi:10.1073/pnas.1115975109.

Tuesday, November 25, 2014

Jurassic World Trailer: Thoughts

Today the trailer for the latest installment of the Jurassic Park franchise, Jurassic World, was released.  If you have not seen it already, check it out below!



I would rather not go and start nitpicking every anatomical inaccuracy about the dinosaurs in this trailer.  I have long ago accepted the fact that Jurassic Park in no way is aiming to be accurate in its renderings. Yes, the theropods don't have feathers, and the sauropod appears to have too many toes, but why are so many of my fellow paleontology nerds acting so surprised?  Jurassic Park was never supposed to be a scientific educational franchise.  Do I wish the dinosaurs looked more realistic to what science tells us so the masses wouldn't continue to get the wrong impressions about paleontology?  Of course.  The reality, however, is this idea isn't Jurassic Park's game and hasn't been since the first two movies.  (which also had flaws)  I get more upset when i see inaccuracies on shows that are supposed to be educational like on the Discovery Channel, for instance.  There is less of an excuse for error there and people watch those programs with the intent to learn facts. 

I'm still excited about this movie.  Honestly, what dinosaur fan wouldn't be?  I know Jurassic Park fans have wanted a marine reptile in a film for a long time.  There was even a plesiosaur metal figure that went with the first line of Jurassic Park toys back in the 1990s (still have mine) but nothing else ever came of it. Now, twenty years later, there is a gigantic mosasaur in Jurassic Park!

nom

May we also please notice how there appears to be trained Velociraptors?  I wonder how long it would take to condition one of them, let alone get it to do what I wanted.  As a zookeeper i can say it takes a lot of work training modern dinosaurs.  I can only imagine what it could be like work with a large dromaeosaur!

Wonder if they used clicker-training... yeah, it was probably clicker training.

 Let's not forget about that mysterious, genetic hybrid that is no-doubt set to be this film's main antagonist.  It isn't seen in the trailer, beyond its feet and front claws a bit.  However, images of some of the upcoming lego toys to go with this movie have been released on the internet and one of them is most likely this new dinosaur.

You have no idea how many times parts of movies have been spoiled by toy companies releasing products and adds before the film hits theaters.

 That's all I really have to say about this trailer.  I may touch on it more in the future.  What are your thoughts on the trailer?  Are you going to see it?  What things are you hoping to see?  Are you disappointed the dinosaurs in the latest film are still scientifically inaccurate?  Do YOU think the Velociraptors were clicker-trained? (Cuz I do.) Let me know in the comments below!

UPDATE: I saw a tweet from one of the writers of the movie.


If I were to nitpick on what the original tweeter said I would say domesticated is not the same as trained but I get the message.  This just solidifies for me that clicker training doesn't always work, especially with Velociraptors.


Thursday, November 20, 2014

Katrina Van Grouw comes to New Jersey

If you have not already please go back and check out my interview with Katrina Van Grouw, former curator of ornithology at the London Museum of Natural History, and revered author and illustrator of the amazing book, The Unfeathered Bird.  These past few weeks Katrina was traveled to the eastern United States all the way from England to give talks about her book.  I was delighted when she contacted me and told me she was going to be in the area and invited her to the Bergen County Zoo where I work to give one of her talks.  Even though I have read her book, hung out with her in person and heard the amazing story of this book's production (which took most of her adult life to do), her talk was nothing less than wildly entertaining and educational too!

We had a room packed with zoo staff, zoo volunteers, local birders, and anyone else in the area with a love and appreciation for ornithology.  Honestly, I think a person not previously interested in birds would be converted having seen this presentation, though.


One of Katrina's main points to her book was that there is so much more to be fascinated by in birds than just feathers.  We tend to focus on the plumage because it is flashy and colorful but there is so much more going on in a bird's body that is just plain fun to learn about.  Below, Katrina explains all the unique adaptations of a woodpecker that allow It to the do what it does without having its eyeballs fly out the back of its little noggin every time it smashes its bill into a tree.


 Katrina's book took so long to publish because neither science publishers nor art publishers were completely sure what to make of the idea.  The science publishers thought it was too art focused and the art publishers thought it was too scientific.  Neither was sure the book would appear to a wide enough audience.  It wasn't until a fateful night in a pub that she got a deal with Princeton University Press.  Smart move, Princeton.

This is true.

Domestic birds are just as strange.  Crested ducks actually have a hole in their craniums where the fluffy crest grows.  This crest ALWAYS matches the color of the duck's flanks, not the rest of its head.  Also, in a genetically confused attempt to make up for the hole in the skull, the duck's skull has a strange hook-shaped horn-like structure growing out of a different part of its skull.  Selective breeding is weird.


In order to get a dead pigeon to appear as if it is inflating its throat sack, sometimes you need to get creative...

Why didn't I think of that!


Thank you again to Katrina for coming down to share your incredible story with us!  If you have not already, definitely grab a copy of Katrina's book, The Unfeathered Bird.

Sunday, November 16, 2014

Dawndraco: Prehistoric Animal of the Week

This week we will be checking out a new discovered species of pterosaur that was discovered way back in the 1970s.  Let's celebrate Dawndraco kanzai!

Dawndraco was a large pterosaur that sported a twenty foot wingspan and soared over the oceans that once covered what is now Kansas, USA, during the Late Cretaceous, 86 million years ago.  Back then a shallow body of salt water covered much of the mid-western United States, called the Western Interior Seaway.  During this time, Dawndraco coexisted with many marine creatures including sharks, like Scapanorhyncus, turtles, plesiosaurs, mosasaurs, like Tylosaurus, and its close relative, Geosternbergia.  Its genus and species name translates to "Dawn Dragon from Kansas".

Fossil remains of Dawndraco kanzai at the American Museum of Natural History in New York.

The discovery and naming of Dawndraco is an interesting story that really starts in 1974 when scientists discovered a beautifully preserved pterosaur skeleton they identified as a Pteranodon sternbergi.  At the time, the genus Pteranodon included two species; Pteranodon longiceps, which had the pointed crests and is the most common pterosaur image in popular culture, and Pteranodon sternbergi, which possessed a wide, triangular-shaped crest.  Fast forward to 2010 and paleontologists are revisiting the Pteranodon genus.  They decided that since Pteranodon longiceps and Pteranodon sternbergi really lived a few million years apart and had very different crests, that Pteranodon sternbergi should get its own genus and so it was renamed Geosternbergia sternbergi.  While they were conducting this research, they realized that the specimen found in the 70s was actually different from both Pteranodon and Geosternbergia.  Its beak was broader longitudinally and the base of its skull was more narrow.  They quickly realized that they had yet another new genus on their hands that had been lying in the museum for decades and never realized it, and thus Dawndraco was born.

Sketch showcasing the three pterosaurs formerly all belonging to the genus, Pteranodon by Christopher DiPiazza.

Dawndraco's wings were exceptionally long and narrow, perfect for soaring over long distances.  This idea is reinforced by the fact that where it was discovered was in the middle of a sea, miles away from any shores at the time that it was alive.  It may have behaved similarly to modern seabirds that also fly long distances over the ocean like Albatross.  Dandraco's beak was extremely long, and possessed no teeth.  Some scientists suggest it hunted prey like small fish and mollusks by plucking them from the ocean's surface as it flew overhead.  Others believe it was more suited to diving into the water and using its long bill and body like a missile to ambush fast-swimming prey.  Dawndraco's skull sadly only preserved the base of the crest so the exact shape of its head ornamentation is somewhat of a mystery.

Life reconstruction of Dawndraco kanzai by Christopher DiPiazza.

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

References

Kellner, A.W.A. (2010). "Comments on the Pteranodontidae (Pterosauria, Pterodactyloidea) with the description of two new species". Anais da Academia Brasileira de Ciências 82 (4): 1063–1084. doi:10.1590/S0001-37652010000400025.

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

Sunday, November 9, 2014

Castoroides: Prehistoric Animal of the Week

This week we shall be checking out yet another R.O.U.S..  Make way for Castoroides ohioensisCastoroides was a kind of beaver that lived from the late Pliocene, about three million years ago, to late Pleistocene epoch, about ten thousand years ago.  Castroides was amongst one of the largest rodents in history, measuring as much as eight feet long from head to tail and weighing almost three hundred pounds in the largest specimens.  During the Ice Age, these bear-sized rodents would have occupied marshes and rivers all over the Western United States, Florida, and parts of Canada. In life, Castoroides would have coexisted with other prehistoric mammals like mammoths, sabre-toothed cats, Glyptodon, giant ground sloths, giant bison, and early humans.  The genus and species name of this animal translate to "beaver from Ohio"...which makes sense!

Castoroides life reconstruction by Christopher DiPiazza.  I made a slight mistake in basing the tail off that of a modern beaver's.  Many scientists believe Castoroides had a more narrow tail, more similar to that of a modern muskrat's.

Castoroides has many physical characteristics in common with modern beavers.  Like its modern relatives, Castoroides had eyes placed on the top and sides of its head.  This would have given it the ability to see in all directions except directly behind it at any one time while still staying mostly submerged in water.  Because of this it could also be assumed that Castoroides probably had webbed digits to help it swim.  Unlike it's modern cousins, Castoroides had proportionally larger feet, shorter legs, a longer tail, and longer, broader incisor teeth, whereas those of modern beavers tend to be short and chisel-shaped.  The molars were also different in Castoroides than in modern beavers.  This implies that Castoroides was not specialized for chewing trees, and would have sustained itself on a different, softer food source, like water plants.  In fact, the teeth of Castoroides, despite being a beaver, in some ways resemble those of other rodents, like Capybaras, which do eat water plants. There is also no evidence on the fossil record that suggests Castoroides ever built dams. 

Castoroides skeletal mount on display at the North American Museum of Ancient Life.

For a long time Castoroides was one of the most successful large mammals in North America, since its fossils have been found in so many different areas.  It is uncertain why they went extinct, but it may have had to do with drastic climate change at the end of the Ice Age.  Large animals, being more specialized and requiring more food and other resources in order to survive, are usually hit hardest and commonly go extinct first, when their habitat changes too rapidly.  Some also suggest that Castoroides may have been hunted too much by early humans for meat and their pelts but so far no evidence has been discovered that proves this. 

That is all for this week!  As always feel free to comment below or on our facebook page!  Have a Request?  Give me a shout out on either of those two places and i will make it happen!

References

Kurtén, B. and E. Anderson (1980). Pleistocene Mammals of North America. Columbia University Press. pp. 236–237. 

Korth, William W (1994). The Tertiary record of rodents in North America. Springer. p. 145. ISBN 978-0-306-44696-2.

 "Giant Beaver: Natural History Notebooks". Canadian Museum of Nature. 2011-05-02.

Friday, November 7, 2014

Olorotitan in Venice

Back in June I attended my friend's birthday celebration at a place called ArteVino in Hoboken, New Jersey.  The place takes private groups and an art instructor guides the group through creating a painting together.  You are even allowed to eat snacks and drink wine!  My friend chose for us to make our own versions of Claude Monet's famous "Sunset in Venice" piece with acrylic paints.  Below is my initial painting just before we finished.


I don't feel like I will ever really be able to compare to Monet's original painting, though.  I needed to add something personal to the painting so it would be different.  Oh, I know...


That's better!  I'm sure an Olorotitan would enjoy Venice if one ever was alive to see it.  That's it for this week, folks!  Stay tuned for this weekend for another prehistoric animal of the week!

Sunday, November 2, 2014

Deinocheirus: Prehistoric Animal of the Week

This week we will be looking at an amazing dinosaur who's remains were discovered almost fifty years ago, but nobody really knew what it looked like truly until this past year.  Make way for Deinocheirus mirificus!  Deinocheirus was a large, feathered dinosaur that measured about thirty six feet long from beak to tail.  It lived in what is now Mongolia, during the late Cretaceous era, between 71 and 69 million years ago. When alive, Deinocheirus was an omnivore, feeding on plants and small animals, like fish.

Deinocheirus mirifacus life reconstruction.

Deinocheirus is a great example of how paleontology is a field where scientists are always learning new things.  This dinosaur, like I stated, was discovered almost fifty years ago, in 1965, in the form of arms.  That's it.  Just a set of huge, eight foot long arms, each tipped with three roughly equally long fingers, armed with curved claws.  It's full name, Deinocheirus mirificus, even translates to "unusual horrible hand" because that is mainly what paleontologists had to study from this animal for a very long time.  These huge mysterious hands and arms were by themselves very impressive.  They were the longest forelimbs from a theropod dinosaur ever discovered!  This caused the imaginations of many people to run wild with visions of a colossal superpredator, using these claws to tear apart any other dinosaur it coexisted with.  When examining the claws and the hands more closely, however, it was discovered that they were most similar to the shape of the arms and hands of ornithomimosaur theropods, like Struthiomimus.  Ornithomimosaurs are characterized by having long, bird-like necks, small heads, and beaks with very small teeth, or in some species, no teeth at all!  Deinocheirus, although big, was most likely not a monster-sized terror if it was anything like its closest relatives.  This is all anyone knew about this dinosaur for many years.  Deinocheirus was just a big set of arms that was often reconstructed as some sort of extra bulky ornithomimosaur...until the mid 2000s when the rest of it was found, and ultimately published this year.  It was revealed that the mysterious Deinocheirus was stranger in appearance than anyone could have ever imagined!

Casts of the Deinocheirus arms found in the 1960s on display at the American Museum of Natural History in New York.

Two, nearly complete between the both of them and what is already known, specimens were unearthed in Mongolia during the mid-2000s.  Amidst their discoveries, poachers actually stole some of the bones and sold them to illegal markets.  These bones were resold a few times in different countries before someone got a hold of them and donated them to the Royal Belgium Museum of Natural Sciences, which in turn, finally returned them to Mongolia with the rest of the skeleton.  What a journey!

So what did these bones tell us about the rest of Deinocheirus?  Where to begin?  Oh!  It had a hump on it's back.  Yes, the neural arches (top portion of the vertebrae) on the back were extremely long and formed a triangular, almost shark-fin shape over the animal's mid-section.  It is believed that these structures would have anchored more muscle for the animal's thighs, sort of like the hump on a modern bison's neck, which attach muscles to the shoulders.

Diagram showing the bones found from Deinocheirus from the journal, Nature, published 10/22/14

Deinocheirus also had a toothless beak, which was narrow near the eyes, then flattened laterally at the tip, which was wide and almost squared off.  The stomach contents found in these new specimens showed the remains of fish and plants.  If we look at modern dinosaurs with similarly shaped beaks, like ducks and spoonbills, we may be able to guess what Deinocheirus was using its beak for.  Interestingly, both ducks and spoonbills also eat small fish and plants.  They use their flat bills to sift through mud and water until they find something suitable to eat, at which point they swallow it whole.  Deinocheirus' stomach also contained over a thousand  gastroliths.  Gastroliths are small rocks swallowed by an animal that doesn't chew its food, to help grind food inside the animal's body.  Gastroliths have been found in many other prehistoric dinosaurs, and are even used today by birds and other reptiles.

Photograph of Deinocheirus' skull and foot bones, as they return to their home country.  Photo is from Mongolia's news site, infomongolia.com

Lastly, Deinocheirus possessed a special bone at the tip of its tail called a pygostyle.  Pygostyles have been discovered on a variety of other dinosaurs, including oviraptorosaurs.  They are mostly seen, however, on birds, and are the site for tail feathers to attach.  This means that Deinocheirus would have had feathers, forming a fan-like shape on its tail, similar to those on a bird.  It is likely Deinocheirus had more feathers on the rest of its body as well. 

That is all for this week!  Deinocheirus is an amazing, fifty-year long story about how paleontologists are always learning new things and how science, although a fact-based field, can certainly change pretty drastically as new data is obtained.  As always feel free to comment below or on our facebook page!

References

Lee, Yuong-Nam; Barsbold, Rinchen; Currie, Philip J.; Kobayashi, Yoshitsugu; Lee, Hang-Jae; Godefroit, Pascal; Escuillié, François & Chinzorig, Tsogtbaatar (2014). "Resolving the Long-Standing Enigmas of the Giant Ornithomimosaur Deinocheirus mirificus". Nature (22 October 2014): 1–4. doi:10.1038/nature13874. PMID 25337880.

Osmólska, Halszka; Roniewicz, Ewa (1970). "Deinocheiridae, a new family of theropod dinosaurs". Palaeontologia Polonica (21): 5–19.

"The "horrible Hand" Deinocheirus Dinosaur's Fossils Are Repatriated to Its Home Country : InfoMongolia.com : News and Information about Mongolia

Thursday, October 30, 2014

Halloween 2014: Thirteen Monsters

Since today is Halloween I feel it would be appropriate to focus on something spooky...like monsters.  Monsters are cool since they can pretty much look like anything your imagination wants them to.  Many dinosaurs and other prehistoric animals are names after famous monsters, or have horror-themed aspects to their names.  Some are pretty obvious, others need to be translated in order to be understood.  Some of these names are featured in my post from 2013 about interesting dinosaur names.  I have illustrated a fun little painting of thirteen prehistoric animals all taking the physical forms of whichever monster or horror aspect they are named after.  Can you name them all?


Once you think you have been able to identify as many as you can I put the answers below, starting with the monsters at the top of the page, working down from left to right.



This plant-eating dinosaur's name means "dragon king from Hogwarts" because its skull resembles that of what a dragon from the Harry Potter universe's could look like.



This small ceratopid's name translates to "gryphon horn face".  Gryphons were creatures from folklore of various ancient Middle Eastern and Mediterranean cultures which were half eagle and half lion.  The first ceratopid fossils found by people thousands of years ago are believed to have sparked the myth of the gryphon. 




Name means "gargoyle reptile".  This was an armored dinosaur that reminded the paleontologists who named it of a stone gargoyle. 

Anthracosuchus balrogus 


This crocodile's genus and species name translates to coal crocodile balrog.  A balrog is a demon, often associated with fire that wields a whip made of flames, from the Lord of the Rings universe.  The character, Gandalf, the grey wizard, battles one in The Fellowship of the Ring.   



Name means "devil horn face" because this ceratopian's horns bear a resemblance to those of demons in pop culture.

Beelzebufo 


Name means "devil frog".  This prehistoric amphibian was the largest frog known to science.



Name means "monstrous murderer".  This was a tyrannosaurid and therefore was likely survived by killing other animals for food...therefore it was a murderer and a monster.  The name is really cool-sounding, okay?



Name means "gore king".  This was another tyrannosaurid predator that, since it also ate meat, was probably exposed to some gore now and again.  Is the name obvious?  Yes.  Is it cool enough to make this fact excusable?  I'd say so.

Minotaurosaurus 


Name means "minotaur reptile" this was an armored dinosaur which was named after the minotaur, a monster from Greek Mythology with the head of a bull and body of a human, because of it's horns.



Name means "Medusa horn face".  This ceratopsian dinosaur was named after Medusa, a monster from Greek mythology called a Gorgon.  Gorgons had snakes for hair, the source of inspiration for this dinosaur's name since its horns were particularly curved and almost wavy like snakes.

Styxosaurus


Name means "Styx reptile".  This plesiosaur was named in honor of the River Styx from Greek mythology, which separates the land of the living from the underworld.

Charonosaurus 


Name means "Charon reptile".  This duck-billed dinosaur was named after Charon, the being from Greek mythology who carries the dead across the Styx to the underworld.



Name means "demon from the river Styx".  Named because its impressive horn arrangement makes it resemble a demon that might lurk in the river of death in a Greek myth.

Hope you enjoyed my little monster-dinosaur fusion!  Happy Halloween!