Tuesday, June 19, 2018

Sinoceratops: Beast of the Week

This week we'll be checking out a large ceratopsian that truly stands out from its relatives.  Enter Sinoceratops zhuchengensis!

Sinoceratops was a ceratopsian dinosaur that lived in what is now China during the late Cretaceous, between 72 and 66 million years ago.  From beak to tail tip it measured just under twenty feet long and like all its relatives, it would have eaten plants when alive.  The genus name translates to "Chinese Horned Face" and the species name is in reference to Zhucheng, the city its remains were discovered in.

Sinoceratops reconstruction in watercolors by Christopher DiPiazza

There were lots of ceratopsian dinosaurs that flourished throughout the Cretaceous.  Sinoceratops is particularly special because it is so far the only known ceratopsid, the family that includes the large kinds of ceratopsians with prominent horns and frill ornamentation, that lived in what is now Asia.  All other known ceratopsids lived in North America.  There are lots of small ceratopsian species known from China from the early Cretaceous, and even the early Jurassic.  It is possible most ceratopsians migrated into North America via a land bridge that existed at the time, called Beringia, and a few stayed back to give rise to Sinoceratops. However, it is also possible, given Sinoceratops' similarities to North American taxa, that some large ceratopsids could have migrated back to China, reslutling in Sinoceratops.

Within ceratopsids there are two major varieties.  The chasmosaurines, are the ones with long frills, and generally have long brow horns and short nose horns. (although exceptions exist).  Triceratops, Chasmosaurus, and Pentaceratops are all examples of chasmosaurines.  Sinoceratops belongs to the other group, the centrosaurines.  Centrosaurines had proportionally taller snouts and generally had large nose horns and small brow horns.  Styracosaurus and Pachyrhinosaurus are both examples from this group.  That being said some older forms of this group had long brow horns and short nosehorns, like Nasutoceratops and Machairoceratops, suggesting that long brow horns were ancestral to ceratopsids before chasmosaurines and centrosaurines split. Sinoceratops is more similar to the later centrosaurines, with a long nose horn and short brow horns, supporting the idea that it shared a more recent common ancestor with the later forms, and therefore was more likely a result of migration back to Asia from North America, instead of being from a lineage that just stayed in Asia the whole time.

Very rough info-graph I put together showing how Sinoceratops ended up in China from North American centrosaurine ancestors.

Sinoceratops is known from a few skulls that show us really interesting horn ornamentation.  The long nose horn and small, basically nonexistent, brow horns are not unheard of in this kind of dinosaur.  However, Sinoceratops had what appears to be knobby structures above its nostrils just in front of the nose horn on either side.  Unfortunately the fossilized skull that has these isn't that well preserved and as far as I know, the texture of the fossil doesn't tell us if these were smaller horn structures, or just the shape of the underlying skull.  This leads to some variation in reconstructions by paleoartists.

Section of Sinoceratops' snout, showing the unusual bony knob just infront of the nose horn.  Photo courtesy of Dr. Andy Farke.

The frill sported a series of narrow horns at its top that grew forwards and curved downwards at the tips.  In addition, the frill, itself, had a series of bumpy knobs along the top and down its center which may have had a layer of keratin, forming shallow horns, in life.     

Close up of the top of Sinoceratops' frill.  In addition to the forward facing horns on the top, you can also see the raised areas on the frame of the frill that may have been shallow horns in life.  Photo courtesy of Dr. Andy Farke.

As usual, the exact purpose of these horns is unknown, but it is possible they were for display within the species, maybe for attracting mates and/or intimidating rivals.  The nose horn could have been a stabbing weapon against predators and the frill horns could possibly have helped by deterring hungry jaws away from the neck. That being said, if defense was the primary purpose for ceratopsid horns, we'd see more uniformity over the millions of years that this branch of dinosaurs evolved.  Display adaptations, however, evolve and change more rapidly.

Portion of Sinoceratops' skull, featuring the eye socket, nose horn, and the little bony knobs over the nostrils.  Photo courtesy of Dr. Andy Farke.

Sinoceratops is featured in the newest installment of the Jurassic Park franchise, Jurassic World Fallen Kingdom.  In the movie it is depicted with two holes in its frill.  Let it be known this isn't backed up by any evidence and almost certainly wasn't the case for the  real animal.  While there were two holes in the skull, like there are in most ceratopsians, they were almost certainly covered up by skin in life.

That is all for this week!  As always feel free to comment below or on the  facebook page.  Special thank you to Dr. Andy Farke for kindly providing the amazing photographs of Sinoceratops' fossil material used in this post.

References

Xu, X., Wang, K., Zhao, X. & Li, D. (2010). "First ceratopsid dinosaur from China and its biogeographical implications". Chinese Science Bulletin55 (16): 1631–1635. 

Wednesday, June 13, 2018

Beast of the Week Reviews Jurassic World Alive

Jurassic World has jumped on the wave caused by the mobile game sensation started by Pokemon Go.  "Jurassic World Alive" uses your phone's GPS to generate a map of your neighborhood (or wherever else you are at the time) with dinosaurs and other  prehistoric animals hanging out in various places.  You walk around until you are close enough to one to collect its DNA (which involves a target-shooting mini game) and then you use that DNA to generate your own specimen of that creature.  You can collect as many of these beasts as you like, make them stronger with more DNA, and even battle them, turn-based style, against other players.  (Although I'm not entirely sure you're really fighting other players.  The last Jurassic World game had a battle system they advertised as player vs player that turned out to be really against a computer once it was noticed how predictable everyone's opponent was.)

I've always seen dinosaurs walking around my neighborhood.  Good to confirm it wasn't just all in my head.  For a second there I thought I might be crazy!

Of course it also wouldn't be a Jurassic World game without freaky hybrids.  In this game you can use the DNA of two creatures to make monstrous hybrids.  Unlike in the last game where you sacrificed your two original creatures to make a hybrid, now you don't lose your original parent creatures when you create a hybrid.  (This is nice since I became rather attached to my Einiosaurus.)  Sometimes you can even combine hybrids you already made to create even weirder hybrids that are a combination of three creatures, instead of two.  To be fair, Indominous rex, from Jurassic World, was a combination of a Tyrannsoaurus, Velociraptor, Majungasaurus, cuddlefish, and a frog.  So think of that before you start whining about triple hybrids in this game.  Science Fiction!

Here's what comes out when you combine a ceratopsian with a pseudosuchian.  That's a thing you know now!

That's all well and good, but what about something for the pure of heart paleontology lovers?  Is this a game for them, too, or just casual Jurassic World fans?  Well I downloaded the game, have been playing it for a bit over a week now, and kept this question in mind the whole time.  Let's dive in!

First thing I want to bring up right off the bat that is that all the prehistoric animals in this game are referred to as a whole as "creatures" in this game, and not "dinosaurs".  This is appreciated since there are more than just dinosaurs to collect in this game, including plenty of pseudosuchians, synapsids, and amphibians.  It's a subtle detail, but it's also one that makes an impact on me.  Countless times I have seen games, toys, shows, movies, and any other kind of entertainment about dinosaurs and other prehistoric life refer to to the whole pool of subjects as "dinosaurs".  This is because the term, "dinosaur" is more charismatic and fun than "prehistoric animals".  I suppose Jurassic World has enough popularity going for it that it can afford to tell it like it is in this regard and not lose any downloads.  Good on them.

So how about the accuracy of the creatures?  The Jurassic Park/World franchise is notorious for making mistakes on accuracy, and sometime straight up actively choosing less accurate designs for the sake of what hey think is better entertainment.  With that in mind I will say up front that any creature that has been featured in any of the films appears in this game true to the way it did on the big screen, accurate or not.  So Dilophosaurus has a frill and spits poison, Velociraptor is featherless, Apatosaurus' neck is too thin...all the same inaccuracies in the movies that paleontology nerds, like myself, have been pointing out at nausea for the past twenty five years, are also in this game.  They do attempt to acknowledge the fact the Velociraptors are over-sized in the flavor text...that's something!  Right?

This fixes everything.  All you nerds can stop whining now.

THAT BEING SAID....when it comes to animals that are not featured in the films, and therefore don't need to uphold any sort of image for recognition sake...some (not all) are actually pretty darn good!  I said something similar in my review of the last mobile game about Jurassic World, two years ago.  This game has actually improved further, having significantly more passable models in this newest game.

Let's start with the most popular instigator of accuracy debates, feathers.  Almost every theropod, specifically coelurosaurians, that we know almost certainly had feathers in life, have feathers in this game.  I'm not talking about the lazy half-attempt few feathers on the head or arms either.  We're talking fully feathered dinosaurs here.  Creatures like Deinocheirus, Proceratosaurus, Utahraptor, and even some of the tyrannosaurids (on which feathers are debatable even scientifically speaking), like Lythronax, sport full coats of plumage.

Plenty of dinosaurs in this game have feathers. 

Frustratingly enough, like I said above, Velociraptor, which has possibly the strongest evidence for feathers in life, is portrayed just like it is in the films in all its naked glory.  I find this particularly amusing when you look at it next to other dromaeosaurids in the game that are portrayed fully feathered.

(top) Utahraptor is appropriately feathered (with a few minor detail mistakes) but sacred Velociraptor (bottom) is the same old naked it's been since the 1993.  Sigh.

In general their large theropods have improved.  Dinosaurs like Suchumimus (which is based on paleoartist, Julius Cstonyi's artwork for the Jurassic World website over two years ago), Megalosaurus, Majungasaurus, and Gorgosaurus are almost totally safe from criticism from me.   The only really glaring problem is that all their wrists are still wrong, with their palms facing down, instead of inwards.  But the the models of these large meat-eaters, especially when compared to those of the same taxa in the last Jurassic World game, are much more accurate.

(top) The pretty terrible excuse for a Megalosaurus from the Jurassic World mobile game, released in 2015, which looks like a warped Tyrannosaurus model.  Compare it to (bottom) the significantly better Megalosaurus in the new Jurassic World Alive game, which is much more accurate.  This is just one example.  Many of the large theropods are much more accurate compared to the last game.

Some of the ornithopod dinosaurs are also really well done.  The one that I was impressed the most by was Edmontosaurus.  I love how the beak actually angles down beyond where the skull's beak would end, which is consistent which what we now know based on a nicely preserved specimen of this dinosaur, now on display in Los Angeles, that shows the keratin beak on top of the bone, proving that it didn't have simply a flat "duck bill".  This is something lots of portrayals of this animal (even scientific ones) get wrong. The Edmontosaurus in this game also has the row of raised scallop-pattern scales running down the back which is also consistent with known hadrosaur fossils.  Nice!

That's a decent hadrosaur!

Of course there are still some models that are just as bad as they were in the last game...or just bad on their own.  The amphibians, like Diplocaulus and Koolasuchus, or some of the pseudosuchians, like Nundasuchus and Postosuchus, come to mind.  The sauropods, ceratopsians, and thyreophorans, while not flat out horrible, all suffer from somewhat subtle inaccuracies in their general anatomies.

At the end of the day, despite how frustrating it is, Jurassic World isn't trying to be scientifically accurate, especially if it gets in the way of what they think will get them better ratings and more money.  That being said, after looking at this game, it is evident that at least some people on creative design team definitely did their homework about these animals and applied what they learned where they could.  This attention to detail is a refreshing oasis of fleeting scientific accuracy in a desert of ignorance.  This game isn't going to fix everything, but it has its positive aspects that the latest movies don't.  Just like with Pokemon Go, it encourages people to go outside and interact with their surroundings, plus it can also help some newer paleontology fans of all ages learn the names of some creatures they may not have known about before. 


Sunday, June 10, 2018

Dilophosaurus: Beast of the Week

This week we will check out a dinosaur that is unfortunately, despite its popularity, is very poorly understood by the general public.  Make way for Dilophosaurus wetherilli!

Dilophosaurus was a meat-eating dinosaur that lived in what is now Arizona, in western North America, during the early Jurassic Period, 193 million years ago.  Trace fossils, like footprints and even a belly imprint of a dinosaur sitting down from the east coast of the United States have also been associated with Dilophosaurus. (or a dinosaur very similar to Dilophosaurus from what we can tell)  The largest specimen measures about twenty three feet long from snout to tail.  The genus name translates to "Two Crested Lizard/Reptile" in reference to the fact that this dinosaur had two, parallel, half-disc-shaped crests on the top of its snout.  The species name is in honor of John Wetherill, a Navajo councilor from near where Dilophosaurus' bones were first found.

Dilophosaurus wetherilli temporarily being startled by a Protosuchus.  The inner monologue here is something like "GAH!...OH, YUM!"

Dilophosaurus was the largest known member of the coelophysoid family of theropod dinosaurs.  Coelophysoids were meat-eating dinosaurs that were highly successful during the late Triassic and early Jurassic periods.  They all were relatively lightly built, had low, narrow snouts, long necks, tails, and legs, hollow bones, and three clawed fingers and one vestigial finger on each hand.  Other examples of coelophysoids are Coelophysis and Liliensternus.

Dilophosaurus' skull is striking.  The first thing you notice are those two crests that grew from the top of the snout.  These crests were made of very thin bone, and probably were too delicate to be used as any sort of weaponry in life.  That being said, they were most likely a kind of display adaptation within the species.  Unfortunately we don't have a large enough pool of complete Dilophosurus skulls to say if they were present in both sexes or not, but they are present in all the complete adult Dilophosaurus skulls on the fossil record so far.

Partially reconstructed Dilophosaurus skull mount on display at the American Museum of Natural History in New York.

Dilophosaurus had a long, slender snout with long, curved teeth that were compressed laterally.  They appear to have been great at slashing and puncturing, but not ideal for crushing or taking any sort of hard impact.  This doesn't seem to have been too much of an issue for Dilophosaurus when you think about its known environment, however.  It was the largest known predator in its environment.  All its prey consisted of much smaller animals, including small, early crocodilians, amphibians, mammals, and sauropodomorph dinosaurs that were about half Dilophosaurus' size.  So Dilophosaurus wouldn't have needed to have had bone-crushing jaws to tackle large prey, because everything it would have been hunting that we know of could have been overpowered with relatively little effort once caught.  In fact, the shape of Dilophosaurus' upper jaw has a deep notch just before the nostril.  This jaw has convergent evolved in other dinosaurs, like spinosaurs, which we know were eating fish in life.  There is a strong possibility that Dilophosaurus was a fisher as well.

Dilophosaurus holotype specimen.  Photo by of Eduard Sola.

One specimen of Dilophosaurus shows multiple injuries that had healed in life.  These include fractures, bony tumors, and even a deformed finger on the right hand.   All of these injuries were concentrated on the arms, hands, and shoulders.  This supports the idea that Dilophosaurus may have used its arms and front claws the most for fighting or subduing prey.  Or maybe it just took a nasty fall or ran into a tree?  Regardless, the point is Dilophosaurus was capable of taking a beating and shaking it off to survive years later!

Oh, and one more thing.  Dilophosaurus was one of the main dinosaurs in the original Jurassic Park.  Its being featured in this movie was sort of a double-edged sword.  On the one hand, an obscure dinosaur, that not many people were familiar with outside the paleontology community, suddenly became insanely popular amongst the general public, and is still highly regarded to this day.  On the other hand, it was portrayed horribly inaccurately, sporting a retractable frill, similar to that of a modern Frilled Lizard, and had the ability to spit venom.  Neither of these features are supported by any fossil evidence whatsoever and were completely made up in the name of showbiz.

References

Milner, A. R. C.; Harris, J. D.; Lockley, M. G.; Kirkland, J. I.; Matthews, N. A.; Harpending, H. (2009). "Bird-like anatomy, posture, and behavior revealed by an Early Jurassic theropod dinosaur resting trace". PLOS One. 4 (3): e4591.

Rothschild, B.; Tanke, D. H.; Ford, T. L. (2001). "Theropod stress fractures and tendon avulsions as a clue to activity". In Tanke, D. H.; Carpenter, K. Mesozoic Vertebrate Life. Bloomington: Indiana University Press. pp. 331–336.

Senter, P.; Juengst, S. L.; Heymann, D. (2016). "Record-breaking pain: the largest number and variety of forelimb bone maladies in a theropod dinosaur". PLOS One.

Welles, S. P. (1984). "Dilophosaurus wetherilli (Dinosauria, Theropoda), osteology and comparisons". Palaeontographica Abteilung A. 185: 85–180.