Month: June 2015

PaleoNews #15

New Findings 

Meet Mystacina miocenalis, the earliest known species of Mystacina, and also the largest. At 40 grams, this bat was 3 times as heavy as its modern relatives. The fossil material of this animal was collected from Lake Manuherikia, which was once surrounded by rainforest around 17 million years ago. The size of this animal suggests that it was doing less in the air and more on the ground, preying on larger animals and eating larger fruits and seeds then its modern relatives. Flightless bats (albeit ones way larger then M. miocenalis) have been the subject of much speculation (i. e. Dixon’s “Night Stalker”, Primeaval’s “Future Predator” , etc.), so the presence of a possible ground-based bat in the fossil record seems to be less of a surprise.

Turtles (or at least their ancestors) are in the news too! The newly-described Pappochelys sheds light on how the turtle shell evolved. In this animal’s case, rod-like bones, some of which fused to each other, coated the underbelly. In life, the animal was around 8 inches long. The animal lived in a tropical lacustrine environment.

 Archelon, a giant protostegid turtle from the Late Cretaceous of North America,  evolved from  a small, lizard-like animal similar to Pappochelys

Archelon, a giant protostegid turtle from the Late Cretaceous of North America, evolved from a small, lizard-like animal similar to Pappochelys. Photo by the author, 2014.

There’s a new prosauropodomorph in town, and its name is Sefapanosaurus. At one point this dinosaur was mistaken for Aardonyx , but Otero et. al. (2015) has concluded that the holotype of Sefapanosaurus is a new species. The animal was collected from the Elliot Formation of Southern Africa many years ago, and, although the specimen is far from complete, the presence of this dinosaur furthers our understanding of Upper Triassic and Lower Jurassic ecosystems.

Prosauropodomorphs, like this Plateosaurus at the AMNH, were very successful during the Late Triassic but started to decline by the earliest Jurassic. Photo by the author, 2015.

Prosauropodomorphs, like this Plateosaurus at the AMNH, were very successful during the Late Triassic but started to decline by the earliest Jurassic. Photo by the author, 2015.

THE INTERNET AND PALEONTOLOGY 

Jaime Headden discusses the new classification  of Balaur blondoc as a basal avalian. Jaime has also created a skeletal of the animal based on this new placement, which he has included in his new article on Balaur. You can find that article here.

Heinrich Mallison brings us an update on his digiS project. Photogrammetry is pretty cool, indeed! Check out his post here.

At Letters from Gondwana, the life and times of part-time paleobotanist and dedicated feminist Marie Stopes. She challenged the societal norms of her time, and her story is one that should be remembered. You can go check out that post here.

Mark Witton discusses speculative behaviors and events pertaining to dromaeosaurs. He also showcases some of his beautiful artwork. You can find that post here.

FEATURED ARTWORK/ PHOTOGRAPH 

This week we have my photo of the Connecticut’s Petrified Forest display at the Yale Peabody Museum. These fossils come from the middle of the state, usually somewhere in the vicinity of South Britain. It’s quite surprising to see how well-preserved these fossil plants are!

IMG_2128Thanks for reading, and I hope you enjoyed!

Advertisements

The Home of Some Antediluvian Beasts of the East : Ramanessin Brook

The coastal seas surrounding Appalachia left behind some of the best preserved fossil specimens in all of the East Coast. One state in particular is famous for its Cretaceous Marine fossils: New Jersey. Every year, private collectors and museum paleontologists alike flock to New Jersey to uncover ancient bones left behind by creatures which lived around 70 million years ago. One of the most famous site is Ramanessin Brook, where not only Cretaceous marine fossils but also Pleistocene fossils can be found.

Commonly, fossils from the Navesink and Wenonah/ Mt. Laurel Formations are found in the brook, providing a glimpse into the ancient past of New Jersey. Fossils dating from the Pleistocene Ice Age are also found in the brook, giving this site a bit of variation in its fossil contents. Ramanessin Brook is known for one thing in particular: shark teeth. Exquisitely preserved shark teeth are a dime-a-dozen when it comes to this place. Although seemingly nothing compared to localities in the west, sites like Ramanessin brook offer us a lot of information on the ancient sea life of the Western Atlantic Ocean.

Scapanorhynchus texanus teeth collected Ramanessin Brook, NJ.  Photo by the author, 2015.

Check out these pretty chompers! Scapanorhynchus texanus teeth collected Ramanessin Brook, NJ. Photo by the author, 2015.

Invertebrate fossils are also found in the sediments of the brook. Partial ammonite shells, belemnite guards, and even giant oyster shells are pretty common at the brook. Here are a selection of invertebrate fossils:

An ammonite carapace collected at Ramanessin Brook. Note that this is a sliver of the whole shell of the ammonite. This carapace fragment most likely belongs to Placenticeras sp. (meeki?), but might also be that of a Sphenodiscus sp. Photo by the author, 2015.

An ammonite carapace collected at Ramanessin Brook. Note that this is a sliver of the whole shell of the ammonite. This carapace fragment most likely belongs to Placenticeras sp. (meeki?), but might also be that of a Sphenodiscus sp. Photo by the author, 2015.

Here is a piece of matrix with some miscellaneous shell fragments and shell imprints. Boy was this tricky to prep! Photo by the author, 2015.

Here is a piece of matrix with some miscellaneous shell fragments and shell imprints. Boy was this tricky to prep! Photo by the author, 2015.

Vertebrate body fossils are even more common then those of invertebrates at Ramanessin Brook. By far the most common are shark teeth. During this trip, shark teeth from at least 5 different species of shark were collected. Common teeth include those of Archaeolamna kopingensis kopingensis Squalicorax kaupi, and Scapanorhynchus texanus. What’s especially interesting is that S. texanus, unlike its modern relative, lived in coastal waters. S. texanus is also the largest known species of Scapanorhynchus. 

Scapanorhynchus texanus lateral tooth. Photo by the author, 2015.

Scapanorhynchus texanus lateral tooth. Photo by the author, 2015.

Porbeagle sharks are represented by a couple genera, namely Archaeolamna kopingensis kopingensis and Cretodus borodini. These were both mid-sized sharks, with A. kopingensis kopingensis reaching 10 feet in length and C. borodini peaking at 7 feet from snout to tail.

Archaeolamna kopingensis kopingensis teeth. Photo by the author, 2015.

Archaeolamna kopingensis kopingensis teeth. Photo by the author, 2015.

The largest sharks in these waters were Squalicorax pristodontus. Only one tooth of this shark was found during my trip. These guys could reach up to 20 feet in length. Even these sharks, however, weren’t the largest predators in the sea, with large mosasaurs like Mosasaurus and Prognathodon also calling the west Atlantic home (Gallagher, 2005).

The ecosystem the Navesink and Mt. Laurel/ Wenonah Formations represent is a coastal sea. As evidenced by the shark teeth above, there was a high diversity of sharks in the Western Atlantic during the Late Campanian/ Early Maastrichtian.

These fossils are also a tricky task to identify in some circumstances. Not much has been published recently on Eastern US deposits (one of the reasons I started the series Antediluvian Beasts) , and so to accurately identify these fossils, we must look at the old literature (I’m taking literature by Joseph Leidy) and the new(ish). I will have much more to say about this site in the future, but for now I wanted to give a brief introduction. For a little more on the animals of Ramanessin Brook, refer to these past articles:

Antediluvian Beasts of The East: Scapanorhynchus texanus 

References 

1.Gallagher, W. B. . 2005. “Recent mosasaur discoveries from New Jersey and Delaware, USA: stratigraphy, taphonomy and implications for mosasaur extinction.”  Netherlands Journal of Geosciences 84(3):241-245

Antediluvian Beasts of the East: Hypsibema crassicauda

The sun distorts the woodland, drying the earth and leaving trees with a greedy countenance. It’s migration season, and the herd marches across the parched landscape with the might of an army. The animals themselves are primarily Hadrosaurus, which bellow to ward off unwanted attention. Then there are the nodosaurs. Nodosaurs aren’t doing very well on Laramidia during the Campanian Stage of the Late Cretaceous, but on Appalachia, they thrive. Armed to the eyelids with spikes and scutes, they pose quite a challenge for predators. Lophorhothon, another type of hadrosaur, is also found within the herd, but these animals are few and far between. None of these dinosaurs, however, are as impressive as Hypsibema crassicauda. The larger of the two species of HypsibemaH. crassicauda can attain lengths of around 50 feet, making the species one of the largest hadrosaur genera, and certainly the largest species of dinosaur present on Appalachia. One of the largest individuals in the herd is a fourteen year old female, who measures 45 feet from beak to tail. Alongside her is another female who is only slightly smaller at 42 feet in length. They triumphantly lead the herd of dinosaurs across the plain, pridefully stomping across the cracked earth below them, as if they were untouchable. The continent of Appalachia, however, is a very dangerous place for a herbivore, and much danger awaits the heard.

To reach a new browsing location, the herd must first cross a thin strip of beach. But there’s death in the water. The lone carcass of a Claosaurus is spotted among the waves, alarming the already-weary herd. They know, however, that they must march on, and they forget about the rotting body.

A few hours pass, and the herd is almost to the forest. Suddenly, a giant Deinosuchus rugosus rushes out of the water, catching a subadult Hadrosaurus between its jaws. Another Hadrosaurus, startled at the sight of the crocodile, bellows to alarm the rest of the herd. A large Hadrosaurus bellows back, trying to scare away the Deinosuchus, which pulls the juvenile hadrosaur down into the abyss.

The Hypsibema are also on guard, but for a different reason. They’ve spotted a lone male Dryptosaurus, and, although he poses little threat, they are weary of him, grunting and snorting to scare the tyrannosaur away. Undaunted, the Dryptosaurus goes about on his patrol, leaving the hadrosauroid giants to browse on the vast expanses of Spruce and Redwood trees which make up the forest behind them.

Hypsibema crassicauda is one of the largest known hadrosaurs. At an estimated 49.2 feet in length (Holtz and Rey, 2007), this member of the hadrosauridae (Horner et. al., 2004) was most likely the largest herbivore in its ecosystem. The holotype, a fragmentary specimen discovered at the King James marl pits in North Carolina, consists of a caudal vertebra, a humerus, a tibia and a metatarsal (Cope, 1869).

The material belongs to a huge hadrosaur. When we look at this Smithsonian specimen of a caudal vertebrae of the animal (which is slightly smaller then the caudal vertebrae included in the holotype), we find the vertebra’s length is approximately 10 centimeters (3.9 inches for the metric-system impaired). If we compare that size with that of a large Edmontosaurus annectens caudal centrum (sadly in private hands), we realize that the Hypsibema crassicauda caudal centrum is approximately 25% larger than that of the Edmontosaurus. Knowing that large E. annectens could reach around 11.9 meters (Sues, 1997), we can estimate the size of H. crassicauda. To do this, we find 25% of 11.9 meters (2.975 meters) and add that to the original 11.9 meters. We end up with 14.875 meters, or 48.8025 feet. Based on the estimated weight of related animals, I also estimate H. crassicauda to have weighed around 17-20 tons. That’s one large hadrosaur!

However, the size estimation method I used is certainly flawed. As Hypsibema crassicauda was a way more basal hadrosaurid than E. annectens, scaling the former from the latter is faulty, due to each of the animal’s different morphological features. Another issue to this method is that scaling an animal from a single bone gives inaccurate answers. Yet Holtz and Rey (2007) also found H. crassicauda to be around 50 feet long and 17 tons (they found it to be 49.2 feet long and “two Elephants” (=14 tons) in weight). If Hypsibema crassicauda did attain this size, it wasn’t just a large hadrosaur, but one of the largest.

I only know of two other non-dubious hadrosaurid taxa which have been estimated to be larger then 49.2 feet in length and 14 tons in weight: Shantungosaurus giganteus at an estimated 54 feet in length (Zhao et. al., 2007)(if Ji et. al., 2011 were right in there analysis that Zuchengosaurus maximus is a junior synonym of s. giganteus) and 18 tons in weight (Horner et. al., 2004), and Magnapaulia laticaudus at between 49.2 and 54.1 feet in length with a weight of up to 25 tons (Morris, 1981). A more recent study, however, has estimated the latter dinosaur to be around 41 feet in length (Prieto-Márquez et. al., 2012). If Prieto-Márquez et. al. (2012) are correct in their size estimate of MagnapauliaHypsibema may be the longest known North American hadrosaurid, and possibly rivals Shantungosaurus giganteus as the longest hadrosaur known to science.

Like other hadrosaurids, H. crassicauda was designed to be an efficient eater. It has even been suggested that hadrosaurids could browse for food sources up to 4 meters above the ground (Mallon & Anderson, 2013). This would make sense for a giant hadrosaurid such as Hypsibema crassicauda, whose body would require an ample daily food supply. I imagine H. crassicauda as the elephant of Appalachia, browsing on anything it could get its beak around. The habitat of this dinosaur would have been woodland, where it would have had a food supply to match its appetite.

The habitat of Hypsibema crassicauda may have been similar to this. Beaver Lake, Colorado. Photo by the author, 2015.

The habitat of Hypsibema crassicauda may have been similar to this. Beaver Lake, Colorado. Photo by the author, 2015.

The size of Hypsibema crassicauda also interests me for another reason. Along with Hypsibema crassicauda, two other species of gigantic basal hadrosaurid are known from the Eastern United States. These are the gigantic Hypsibema (=Parrosaurus) missouriensis from Missouri (estimated at around 50 feet and 14 tons as well (Holtz and Rey, 2007), although this animal seems to be smaller then H. crassicauda) and Ornithotarsus immanis from New Jersey, a possible synonym for Hadrosaurus foulkii (Prieto-Marquez, A., Weishampel, D. B. & Horner, J. R., 2006) (which is estimated to be 39.6 feet in length and 7 tons in weight (Holtz, 2012). The location of these animals (did I mention Hypsibema crassicauda material is reported to have been found in NJ?) shows that gigantic hadrosaurids in the 40-50 foot, 10-20 ton size range were very widespread across Appalachia during the Late Cretaceous, whereas on Laramidia, only one hadrosaur taxa has been estimated to be around that size range, the lambeosaurine Magnapaulia laticaudus. And even these lambeosaurine giants had competition. The morphological similarities of lambeosaurine and ceratopsid dinosaurs might have been the reason that they weren’t able to coexist for long periods of time due to competitive exclusion (Mallon & Anderson, 2013).

So why were there so many gigantic basal hadrosaurids on Appalachia? I believe the reason was the lack of the ceratopsids and highly derived hadrosaurids. Ceratopsids were most likely low-level browsers, using their strong beaks to ingest tough plant matter (Mallon & Anderson, 2013), and lambeosaurines probably occupied similar regions of morphospace (Mallon & Anderson, 2013). The possible scarcity of these groups on Appalachia (so far, we haven’t found any ceratopsian remains on the East Coast, and lambeosaurine remains, though present (Gallagher, 2002) are seldom found, and only from Maastrichtian deposits) might have allowed more basal forms to thrive.

Could the absence Ceratopsid and derived hadrosaurid dinosaurs on Appalachia allow basal hadrosaurids to thrive and grow to gigantic size? Photo: Skull of a Triceratops. Photo by the author, 2015.

Could the absence of ceratopsid and derived hadrosaurid dinosaurs on Appalachia allow basal hadrosaurids to thrive and grow to gigantic size?
Pictured: Skull of a Triceratops, a ceratopsid dinosaur. Photo by the author, 2015.

And yes, I know what you are thinking:

So what about saurolophinae? You said derived hadrosaurs earlier, not just lambeosaurines.

A couple of possible saurolophine dinosaurs are known from Appalachia. I have heard that the Alabama taxon Lophorhothon atopus was suggested to be a saurolophine, but only as a juvenile Prosaurolophus. More recent analyses have concluded that L. atopus is a basal hadrosauroid (Prieto-Marquez & Salinas, 2010). Although some have suggested the presence of Edmontosaurus sp. at the Ellisdale site (Gallagher, 1993), a Marshalltown Formation exposure which is around 72 million years old, this dinosaur’s presence at Ellisdale is tentative at best, and the reported  “Edmontosaurus sp.” remains are probably just those of a Hadrosaurus or of an indeterminate hadrosaur.

The skeleton of Edmontosaurus, a saurolophine dinosaur, at the Yale Peabody Museum. Photo by the author, 2014.

The skeleton of an Edmontosaurus, a saurolophine dinosaur, at the Yale Peabody Museum. Note the featherless Deinonychus photobombing. Photo by the author, 2014.

Another question might be about competitive exclusion between East Coast nodosaurs and giant hadrosaurids. Mallon & Anderson (2013) also covers this for us. Their analysis concluded that ankylosaurs were the least likely to compete with other large herbivores.

If the lack of ceratopsids and derived hadrosaurs is what allowed the large basal hadrosaurids of the East Coast to thrive, then the presence of these groups might have also caused the downfall of hadrosaurian giants like Hypsibema crassicauda. The Navesink Formation, a Maastrichtian-age deposit, bears both the remains of (possible) lambeosaurines (Gallagher, 2002) and smaller, more basal hadrosaurids, such as Hadrosaurus (Gallagher et. al., 1986), found on Appalachia prior to the closing of the Western Interior Seaway (AMNH 7626, attributed to Hadrosaurus, from the Campanian, for example). It seems to me that the immigration of west-originating dinosaur groups to the Eastern US is correlated with the disappearance of large basal hadrosaurids on Appalachia. The giant basal hadrosaurids of Appalachia were simply out-competed. If lambeosaurines were indeed migrating to the Eastern US, it might also have been the case that native East US forms headed westward. The end result would be the odd giant basal hadrosaur in a western Maastrichtian deposit, like Hell Creek. Others have also speculated about the presence of these animals in the west.  These animals must have been very rare occurrences, though, as I do not know of any dryptosaur and/or giant basal hadrosaurid remains reported from Hell Creek or any other western Maastrichtian deposits. If ACDs (Alien Coast Dinosaurs is what we will call these migrants from now on) existed in both the west and the east, we would be looking at a cross-continental dinosaur migration occurring in the time range of 2-3 million years. I will talk more about this concept in later installments of Antediluvian Beasts, so for now, keep this idea in mind.

Many other types of animals uncommon or absent in the west coexisted with Hypsibema crassicauda. On Appalachia, the dryptosaurs were among the top terrestrial predators, whereas in the west, derived tyrannosaurids ruled the roost. We know H. crassicauda existed alongside dryptosaurs due to the presence of H. crassicauda at Ellisdale (Grandstaff et. al., 1992) alongside Dryptosaurus sp. (Grandstaff et. al.,1992). It’s possible that the gargantuan hadrosaur might have even fallen prey to the dryptosaurs present in its environment.

So what were the dynamics of Hypsibema crassicauda’s environment, exactly? In the southern part of H. crassicauda’s known range, it would have co-existed with other hadrosaurs, such as Hadrosaurus minor (Lull & Wright, 1942), and theropods such as Ornithomimus antiquus (Baird & Horner, 1979). At Ellisdale, the gigantic hadrosaurid would have shared the woodland with Hadrosaurus (Grandstaff et. al, 1992), Ornithomimus (=Coelosaurus)(Denton & Gallagher, 1989), and the predatory theropod Dryptosaurus (Grandstaff et. al., 1992).  The variation of sizes among the hadrosaurs present in the environments mentioned above (Hypsibema crassicauda grew to 48.8 feet in length, whereas a Hadrosaurus would reach 26 feet in length (Holtz, 2012)) suggests that niche partitioning might have evolved between these dinosaur genera. Hadrosaurus could have been the low-browsing deer to Hypsibema’s variety-browsing elephant. So many hadrosaur species of varying sizes from the Late Campanian and Early Maastrichtian of the East Coast are known (i.e. Hadrosaurus foulkii, Hadrosaurus cavatus, Ornithotarsus immanis, Hadrosaurus minor, etc.), that it is hard to imagine the absence of niche partitioning among these dinosaurs.

Hypsibema crassicauda‘s kind would survive until the end of the Cretaceous, with forms like Hadrosaurus minor surviving into the Maastrichtian, their remains deposited in the Navesink Formation (Gallagher et. al.,  1986). The giant basal hadrosaurids, however, would decrease in number, being replaced by the lambeosaurines and edmontosaurinines which were able to arrive from the west as the Western Interior Seaway had closed. The KT extinction event finally sealed the giant hadrosaurs’ fate, their bones left to dry in the hot, crackling dirt.

Hypsibema crassicauda by the author. Colored pencils on paper, 2015.

Hypsibema crassicauda by the author. Colored pencils on paper, 2015.

 References 

1. Holtz, T. R. Jr.; Rey, L. V. .2007. Dinosaurs: The Most Complete, Up-to-Date Encyclopedia for Dinosaur Lovers of All Ages. New York: Random House. p. 409. 

2. Horner, J. R.; Weishampel, D. B.; Forster, C. A. .2004. “Hadrosauridae”. In Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.). The Dinosauria(2nd ed.). Berkeley: University of California Press. pp. 438–463.

3. Cope, E. D. .1869. “Remarks on Eschrichtius polyporus, Hypsibema crassicauda, Hadrosaurus tripos, and Polydectes biturgidus.” Proceedings of the Academy of Natural Sciences of Philadelphia 21: 191-192.

4. “Hypsibema crassicauda” Collections Search Center, Smithsonian Institution. Smithsonian Institution. URL: http://collections.si.edu/search/results.htm?q=Hypsibema+crassicauda . Accessed June 10, 2015.

5. Sues, H-D. (1997). “Ornithopods”. In Farlow, James O., and Brett-Surman, Michael K. (eds.). The Complete Dinosaur. Bloomington: Indiana University Press. p. 338.

6. Zhao, X.; Li, D.; Han, G.; Hao, H.; Liu, F.; Li, L.; Fang, X. .2007. “Zhuchengosaurus maximus from Shandong Province.” Acta Geoscientia Sinica 28 (2): 111–122.

7. Ji, Y., Wang, X., Liu, Y., and Ji, Q. .2011. “Systematics, behavior and living environment of Shantungosaurus giganteus (Dinosauria: Hadrosauridae).” Acta Geologica Sinica 85(1): 58-65.

8. Morris, W. J. .1981. “A new species of hadrosaurian dinosaur from the Upper Cretaceous of Baja California: ?Lambeosaurus laticaudus.” Journal of Paleontology 55(2): 453–462.

9. Prieto-Márquez, A.; Chiappe, L. M.; Joshi, S. H. .2012. Dodson, Peter, ed. “The lambeosaurine dinosaur Magnapaulia laticaudus from the Late Cretaceous of Baja California, Northwestern Mexico.” PLoS ONE 7 (6): e38207.

10. Mallon, J. C.; Anderson, J. S. .2013. “Skull Ecomorphology of Megaherbivorous Dinosaurs from the Dinosaur Park Formation (Upper Campanian) of Alberta, Canada.” PLoS ONE 8(7): e67182.

11. Prieto-Marquez, A.; Weishampel, D. B.; Horner, J. R. .2006. “The dinosaur Hadrosaurus foulkii, from the Campanian of the East Coast of North America, with a reevaluation of the genus.” Acta Palaeontologica Polonica 51: 77-98.

12. Holtz, T. R. Jr; Rey, L. V. .2007. Dinosaurs: the most complete, up-to-date encyclopedia for dinosaur lovers of all ages. New York: Random House. (Updated during 2012) link: PDF .

13. Gallagher, W. B. .2002. “Faunal changes across the Cretaceous-Tertiary (K-T) boundary in the Atlantic coastal plain of New Jersey: restructuring the marine community after the K-T mass-extinction event.” Catastrophic Events and Mass Extinctions: Impacts and beyond. GSA Special Paper 356:291-301.

14. Prieto-Marquez, A.;  Salinas, G. C. .2010. “A re-evaluation of Secernosaurus koerneri and Kritosaurus australis (Dinosauria, Hadrosauridae) from the Late Cretaceous of Argentina.” Journal of Vertebrate Paleontology 30(3): 813-837.

15. Gallagher, W. B. .1993. “The Cretaceous/Tertiary mass extinction event in the North Atlantic coastal plain.” The Mosasaur 5:75-154.

16. Grandstaff, B. S.; Parris, D. C.; Denton, R. K. Jr.; Gallagher, W. B. .1992. “Alphadon (Marsupialia) and Multituberculata (Allotheria) in the Cretaceous of Eastern North America.”  Journal of Vertebrate Paleontology 12(2): 217-222.

18. Lull, S; Wright, N. E. .1942. “Hadrosaurian dinosaurs of North America.” Geological Society of America Special Paper 40:1-242.

19. Baird, D.; Horner, J. R. .1979. “Cretaceous dinosaurs of North Carolina.” Brimleyana 2:1-28.

20. Denton, R. K.; Gallagher, W. .1989. “Dinosaurs of the Ellisdale site, Late Cretaceous (Campanian) of New Jersey.” Journal of Vertebrate Paleontology 9(3, suppl.):18A.

21. Gallagher, W. B.;  Parris, D. C.; Spamer, E. E. .1986. “Paleontology, biostratigraphy, and depositional environments of the Cretaceous-Tertiary transition in the New Jersey coastal plain.” The Mosasaur 3:1-35.

EDIT: The remains of a leptoceratopsid have been reported from the Tar Heel Formation of Cretaceous North Carolina. This shows that ceratopsians were present on Appalachia. However, the presence of leptoceratopsids on Appalachia does not automatically imply that the generally larger ceratopsids were present as well.

Terrific Tetanurae #11 Pyroraptor olympius

During the Late Cretaceous, what is now the continent of Europe was split into a multitude of islands, where both flora and fauna evolved into weird and wonderful forms. Unlike anywhere else in the northern hemisphere during the Late Cretaceous, these islands were home to abelisaurids, like the french form Arcovenator, which most likely took up the niche of top predators in their ecosystems (that is, if they weren’t in competition with island-hopping azhdarchids).

The skull of Majungasaurus crenatissimus, an abelisaurid. Photo by the author, 2015.

The skull of Majungasaurus crenatissimus, an abelisaurid. Relatives of M. crenatissimus existed where France is now during the Late Cretaceous. Photo by the author, 2015.

Dromaeosaurids are also present on these islands. Among their ranks is the obscure dinosaur Pyroraptor olympius, a Maastrichtian form native to where France is today. 

Giant Azdarchids, similar in size to the North American Quetzalcoatlus, also called Late Cretaceous Europe home. Quetzalcoatlus humerus replica at the AMNH. Photo by the author, 2014.

Giant Azdarchids, similar in size to the North American Quetzalcoatlus, also called Late Cretaceous Europe home. Quetzalcoatlus humerus replica at the AMNH. Photo by the author, 2014.

Pyroraptor is known from fragmentary remains which were described by Allain and Taquet in 2000. Because of the fragmentary nature of the specimen, it is hard to estimate the size of this animal, but the bones indicate an animal of around 1.5 meters in length. Since the awesomebro dromaeosaurid stocky dragon has been recently reclassified as a basal avalian (Cau, Brougham, & Naish, 2015), Pyroraptor once again is one of only two known dromaeosaurids from the Late Cretaceous of Europe. The other dromaeosaurid is Variraptor, dromeosaurid which varies in its validity. Some have suggested that Variraptor and Pyroraptor represent the same animal, which would mean, by the laws of nomenclature, that Variraptor, the older of the two scientific names, would take priority. However, Chanthasit & Buffetaut (2009) argued that Variraptor indeed is a distinct taxon, and that the presence of two morphologically different types of ulna would assure that both of these dromeosaurid taxa are valid.

P. olympius would have probably coexisted with rhabodont and titanosauriform genera, both of which were present in Europe during the Late Cretaceous. The small size of Pyroraptor suggests that it would not have gone after full grown individuals of either group. Rather, it would stick to smaller prey, such as fish, small squamates and amphibians, eggs, and possibly infant dinosaurs.

Dinosaur eggs, a favorite snake of Pyroraptor's. Unfortunately, the eggs pictured come from Mongolia, and so Pyroraptor would never get a chance to eat them.

Dinosaur eggs, a favorite snake of Pyroraptor’s. Unfortunately, the eggs pictured come from Mongolia, and so Pyroraptor would never get a chance to eat them.

While abelisaurids and azhdarchids ruled the roost as top predators, Pyroraptor would be much more at home scurrying across the forest floor, perusing the leaf litter for its next potential meal.

Pyroraptor with prey by the author. Pencils on paper, 2015.

Pyroraptor with prey by the author. Pencils on paper, 2015.

References 

1. Allain, R.; Taquet, P. .2000. “A new genus of Dromaeosauridae (Dinosauria, Theropoda) from the Upper Cretaceous of France.” Journal of Vertebrate Paleontology 20: 404-407.

2. Cau, A; Brougham, T; Naish, D. .2015. “The phylogenetic affinities of the bizarre Late Cretaceous Romanian theropod Balaur bondoc (Dinosauria, Maniraptora): dromaeosaurid or flightless bird?” PeerJ 3: e1032. 

3. Chanthasit, P.; Buffetaut, E.  .2009. “New data on the Dromaeosauridae (Dinosauria: Theropoda) from the Late Cretaceous of southern France.” Bulletin de la Société Géologique de France 180(2):145-154

Jurassic World: A Fun Monster Movie

For starters, this is the nicest review I could come up with. I hated the sexism and cheesy acting in the movie, and I was actually rooting for the monsters and not the humans. Running in high heels? Really? I will restrain my anger for now, though.

I had the opportunity to see World with a couple of my good friends. Although the movie has really inaccurate depictions of dinosaurs, it isn’t (hopefully) supposed to be factual. The movie really ends up being about respect for the natural world. Indominus rex was created in order for the park to reap in cash, and is treated by many of the characters as just an “asset”. The animal escapes its cage, killing much anything it can get its hands on. During this process, the Jurassic World staff learn that the genetically modified animals they call dinosaurs are living, breathing animals, and not just money making attractions. Indominus rex is the manifestation of the insatiable greed of humanity, a theme common in all of the Jurassic Park movies.

There is one scene in the movie which I found particularly well-shot. At one point, the main geneticist and the owner of the park are conversing in the genetics lab while the I. rex is causing chaos on the island. The geneticist tells the owner that the animals in the park aren’t real dinosaurs, but just genetic hodgepodges made to reap in cash. He touched my paleontology-lovin’ heart when he said that real dinosaurs would look very different. Another one of the geneticist’s lines during the scene was fantastic as well. “To a canary, a cat is a monster. We are just used to playing the cat”. That line perfectly delivers the danger of human arrogance, capturing the central idea of Jurassic Park and its sequels.

I found the movie itself pretty fun to watch, and, though not as good as the original, better then the second and third sequels. Even though World isn’t factual, it definitely hits upon some important issues coming up in modern society. World isn’t meant to be an all-around-science-based movie, – Jurassic Park wasn’t either – but it is good that we paleontologists and paleo-enthusiasts point out its inaccuracies. The common person, I’m afraid, most likely does not understand the magnitude in which the JW monsters differ from their real counterparts. Some people are just hooked on to the Jurassic Park portrayals of dinosaurs, arguing against actual scientists in order to keep their mental images of scaly, hand-pronating dinosaurs the same. Jurassic World, though not meant to be a science-based film, would be greatly improved with accurate depictions of dinosaurs, surprising us just as the original surprised us with the most up-to-date dinosaurs on the big screen in 1993.

Growl!

Growl!

PaleoNews #14

Hello everyone! This is PaleoNews, where I showcase the latest in paleontological discoveries! 

NEW FINDINGS 

A new horned dinosaur showing signs of convergent evolution has been described! Regaliceratops was a large ceratopsian, up to 6 meters long, which was closely related to Triceratops, and shows features found in chasmosaurines as well as centrosaurines. This is strikingly odd, as the animal itself was a chasmosaurine. The centrosaurine features found present in Regaliceratops might be convergent evolution among the ornaments of horned dinosaurs. Regaliceratops itself is known from a mostly complete skull, which bears an impressive nose horn, two minuscule orbital horns, and large, stegosaur-plate-shaped epoccipitals. The genus name Regaliceratops pays homage to these large epoccipitals, translating to “Royal horned face”. The animal was excavated from the St. Mary River Formation, a Maastrichtian deposit. Other ceratopsids also are found in this formation, as well as the large tyrannosaurid Albertosaurus. 

Regaliceratops by the author. Pencils on paper, 2015.

Regaliceratops by the author. Pencils on paper, 2015.

New vertabral centra reveal that giant Cretaceous sharks might have been more common then expected.Leptostyrax macrorhiza is the Cretaceous shark these remains have been thought to be, and if so, Leptostyrax might have attained a length of up to 20 feet in length. This is important as it adds to our understanding of Early Cretaceous marine environments.

A new species of reptile has been described. Clevosaurus sectumsemper is an extinct sphenodont from the Triassic period, and it is named after a spell in that popular book series which I am sick of hearing about (it’s my unpopular opinion). As always, animals like this new taxa show the ancient diversity of a now dwindling group of animals.

A new enantiornithine bird from Gondwana has been discovered. This small avian dinosaur lived around 115 million years ago and is a rare discovery in a land filled with the bones of giant saurischian dinosaurs. The bird is as yet not described, but, as always, I’d rather the authors do a good job with the description then put out a rushed paper.

Soft tissue from dinosaur bones has been discovered. An examination of fragmentary dinosaur bone remains seems to have found preserved tissues and structures. This, if true, would be a landmark find in paleontology and help us understand the paleobiology of dinosaurs much better. I can only imagine what we could find out from looking at the cells of dinosaurs.

THE INTERNET AND PALEONTOLOGY 

On his blog, Mark Witton discusses Dimorphodon’s awesomeness. It’s quite an interesting post, which you can view here.

At SV-POW!, Mike discusses the reasons we might never find the largest dinosaurs. He brings up some very good points, and I definitely recommend you check it out here. Also check out this great post on Haestasaurus. 

At Extinct Monsters, Ben discusses the history of 3 very iconic tyrannosaurs, some of which are now hidden behind the presently mounted AMNH Tyrannosaurus rex. The post can be viewed here, and it’s quite an interesting read.

Twilight Beasts discusses camels, camels, and more camels. Camel over here to read the post.

FEATURED ARTWORK/ PHOTOGRAPH 

This week we have my photo of the famous AMNH Deinocheirus arms:

Photo by the author, 2015.

Photo by the author, 2015.

I hope you enjoyed PaleoNews #14. Thanks as always for reading!

Terrific Tetanurae #10 The Wealden Tetanuran

Yay! We have reached the tenth addition of Terrific Tetanurae! 300 views in May and now this! That’s awesome! Thanks everyone for your continuous support, and enjoy the article! 

Remember the post on Mark Witton’s blog I linked to in the last addition of PaleoNews? Well, the second addition of that art showcase has since come out and got me wondering with Mark’s mention of the presence of basal tetanurans in the supergroup. I’ve done some snooping, and it turns out the subject of basal tetanurans in the Wealden Supergroup is quite interesting, and deserves to be discussed on this blog.

Now I am no expert on Wealden fauna, but the supergroup holds a special place in my heart for a reason. Like the Cretaceous fauna of the East Coast, which, as I’ve mentioned, is one of my primary research areas (that and the paleobiology of carcharodontosaurid dinosaurs), much of what we know about the fauna of the Wealden Supergroup is based on highly fragmentary remains. Sure, the occasional gems like the partial and mostly complete specimens of animals like Neovenator, Baryonyx, Eotyrannus, Iguanodon, and various iguanodonts are incredibly important to our understanding of the paleoecology of the environment the supergroup represents, but more fragmentary specimens like that of the “Ashdown Maniraptoran” also tell us a good amount about the Wealden ecosystem.

Today, the tetanuran we will be talking about was described by Benson et. al. in 2009, and from what we can tell, it was pretty big. This animal hails from the Wessex Formation (Benson et. al., 2009) where it coexisted with such theropods as the tyrannosauroid Eotyrannus (Hutt et. al., 2001). This theropod is classified as a basal tetanuran (Benson et. al., 2009), but you would probably hypothesize this animal an allosaurid if you only heard “Large Basal Tetanuran from Wessex Formation”. Yet, the specimen differs a good amount even from Neovenator (see this post by Darren Naish for more not-contained-within-a-scientific-paper information on the differences between this theropod and Neovenator),supporting the animals status as a basal tetanuran outside of allosauroidea. The presence of this animal is quite unique among the terrestrial ecosystems of the Early Cretaceous, as, during this time, allosaurids, such as Acrocanthosaurus, were the most common large predators on land.

Allosaurids, like the carcharodontosaurid Mapusaurus, were the more common large predators of the Early and mid-Cretaceous. Artwork by the author, 2015.

Allosaurids, like the carcharodontosaurid Mapusaurus, were the more common large predators of the Early and mid-Cretaceous. Artwork by the author, 2015.

The presence of this theropod in the Wessex Formation shows that that environment could support multiple medium-sized and large predators, as Eotyrannus  and Neovenator are also present in the Wessex Formation (Benson et. al, 2009, Hutt et. al., 1996). This has implications for understanding the biomass of prey fauna in the Wessex Formation, but also might have something to do with niche partitioning.

The Wealden Tetanuran by the author. Colored pencils on paper, 2015.

The Wessex Formation Basal Tetanuran by the author. Colored pencils on paper, 2015.

Overall, this tetanuran shows how much we can learn about the paleoecology of a formation from fragmentary specimens. This theropod, at its heyday, would have taken up a predatory niche, hunting the various ornithopods and sauropods of the formation. The Early Cretaceous, however, would be the only time this animal would thrive. Along with the giant allosaurids of the Early and mid-Cretaceous (~145-90 MYA), this tetanuran would be replaced by the larger abelisaurids and tyrannosauroids of the Late Cretaceous, such as Carnotaurus sastrei and Tyrannosaurus rex. 

Large tyrannosauroids, like T. rex, replaced the large basal tetanurans and allosaurids of the Early and mid-Cretaceous as top predators during the Late Cretaceous. Photo by the author, 2015.

Large tyrannosauroids, like T. rex, replaced the large basal tetanurans and allosaurids of the Early and mid-Cretaceous as top predators during the Late Cretaceous. Photo by the author, 2015.

References 

1. Benson, R. B. J.; Brusatte, S. L.; Hutt, S.; Naish, D. 2009. “A new large basal tetanuran (Dinosauria: Theropoda) from the Wessex Formation (Barremian) of the Isle of Wight, England.” Journal of Vertebrate Paleontology 29: 612-615.

2. Hutt, S.; Naish, D.; Martill, D.M.; Barker, M.J.; Newbery, P. .2001. “A preliminary account of a new tyrannosauroid theropod from the Wessex Formation (Cretaceous) of southern England.” Cretaceous Research 22: 227–242.

3. S. Hutt; D. M. Martill; M. J. Barker. 1996. “The first European allosauroid dinosaur (Lower Cretaceous, Wealden Group, England).” Neues Jahrbuch für Geologie und Paläontologie Monatshefte 1996(10):635-644.