Hadrosaurus: Beast of the week

Today we honor a very special dinosaur.  A dinosaur that not only has roots in New Jersey, but holds significance to American paleontology as a whole.  Enter Hadrosaurus foulkii!  Hadrosaurus was a plant-eating dinosaur that lived in what is now New Jersey, USA, during the Late Cretaceous about 79 million years ago.  It is known from the majority of a skeleton, minus the skull (bummer), and would have been about twenty five feet long from beak to tail.  Since it was the first of its kind to be discovered, Hadrosaurus' name is used as the family name, hadrosauridae, for the entire group of duckbill-dinosaurs, like Anatotitan, Maiasaura, Parasaurolophus, and Tsintaosaurus.  Its genus name translates to "Bulky Lizard" and the species name is in honor of William Parker Foulke, who took part in its discovery.

Life reconstruction of Hadrosaurus foulkii by Christopher DiPiazza.

Hadrosaurus is a very important dinosaur not just because it was found in New Jersey, but because it was actually the first scientifically recognized dinosaur ever dug up in all of the United States!  This dinosaur's bones were found in what is now Haddonfield, New Jersey, in 1838.  The man who discovered the first of its bones actually used them as decorations on his house until they were noticed by William Parker Foulke.  Foulke was intrigued by these bones and ended up digging out more of them from where the original specimens were unearthed.  Paleontologist, Joseph Leidy, correctly identified the bones as belonging to a dinosaur because of their similarity to those of Iguanodon, which had been discovered during the 1820s in England.

Known skeleton of Hadrosaurus foulkii on display at the Academy of Natural Sciences in Philadelphia, PA.

In 1868, a skeletal mount of Hadrosaurus was erected at the Philadelphia Academy of Natural Sciences, making it the first dinosaur skeleton to be mounted in the world.  Since the skull was never found, a skull was sculpted based somewhat on modern iguanas, since dinosaurs were thought to be more closely related to lizards during that time, given the little information that was known.  It was also, however, posed standing on its hind legs which was previously unheard of for reptiles, let alone dinosaurs.  We now know that Hadrosaurus would have definitely been able to stand and walk on its hind limbs and despite the fact that a skull was never actually found, it almost certainly had a broad, flattened beak of some sort like the rest of its hadrosaur kin.

Photograph of the original Hadrosaurus skeletal mount.  Note the lizard-like skull.

Exactly how the beak and the shape Hadrosaurus' skull would have looked is somewhat of a mystery, but according to the most recent studies done on the hadrosaurid family, Hadrosaurus appears to be one of the more basal of the "true duck-billed" dinosaurs, called the hadrosaurines.  This means that it was less related to the lambeosaurine hadrosaurs, which are known for having elaborate crests, like Parasaurolophus, and was closer to the more broad-billed hadrosaurs, like Edmontosaurus.  The dinosaurs most closely related Hadrosaurus within this group have slightly downturned snouts, like that of Maiasaura, which lived a few million years after Hadrosaurus, so Hadrosaurus' skull may have looked similar.

Hadrosaurus skeletal mount on display at the Academy of Natural Sciences.  Skull is a cast of a relative, Maiasaura.

When the subject of paleontology comes up in a casual conversation (because when you hang out with dorks like me it does a lot) most envision people digging in deserts out west in states like Utah, New Mexico, or the Dakotas.  While this is true in a lot of cases, ground zero for American dinosaur fossil sites is actually in a wooded area in little old New Jersey.  Because of this, New Jersey was the first state to give itself an official state fossil, Hadrosaurus.  This means that we have two state dinosaurs, because our state bird, the Goldfinch, is a dinosaur...because birds are dinosaurs.

A dinosaur.

References

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.

Prieto-Márquez, A. (2011). "Revised diagnoses of Hadrosaurus foulkii Leidy, 1858 (the type genus and species of Hadrosauridae Cope, 1869) and Claosaurus agilis Marsh, 1872 (Dinosauria: Ornithopoda) from the Late Cretaceous of North America". Zootaxa 2765: 61–68.

Prieto-Marquez, A., Weishampel, D.B. and 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(1): 77–98.

Xing, Hai, et al. “Supplementary Cranial Description of the Types of Edmontosaurus Regalis (Ornithischia: Hadrosauridae), with Comments on the Phylogenetics and Biogeography of Hadrosaurinae.” Plos One, vol. 12, no. 4, 2017, doi:10.1371/journal.pone.0175253.

Prehistoric New Jersey: Woodbury Formation

I am proud to have been born and raised in New Jersey.  Not because our bagels are the best, or because our pizza is just as good as New York's (it's true). I never really listened to Sinatra that much nor did I ever watch more than a few episodes of The Sopranos.  I'm proud to be from New Jersey because it is the site of the first scientifically-recognized fossil dinosaur.  Furthermore, New Jersey was the first state to adopt that dinosaur, Hadrosaurus foulkii, as its official state fossil.  As a dinosaur-crazed kid, of course I knew all the staples, like Tyrannosaurus and Triceratops, but Hadrosaurus and Dryptosaurus (second fossil dinosaur found in New Jersey), were also part of my off the cuff repertoire.

All this being said, it wasn't until recently that I finally made the pilgrimage to the site where Hadrosaurus was found.  I don't really have a good excuse why it didn't happen earlier.  I suppose it was one of those situations where I kept putting it off because I knew it was always going to be there.  Regardless, today, we are going to recap the site and what it has to offer for anyone who chooses to visit.

The site is called the Woodbury Formation and is located in Central New Jersey, in a town called Haddonfield.  The town is named after Elizabeth Haddon, one of its earliest settlers.  Hadrosaurus' genus name translates to "bulky reptile" however.  I don't know if the similarity between the dinosaur's name and the town's name was a coincidence or not to be honest.

In the middle of downtown Haddonfield, an almost-life-size statue was erected in the early 2000s of Hadrosaurus.  The statue is reasonably accurate for its time, although there are a few glaring inaccuracies.  It's lacking a defined beak, which Hadrosaurus, and all members of its family would have had in life, being most notable.  I was told the artist was inspired by horse mouths when sculpting the Hadrosaurus, which explains the fleshy lip-like look.  The nostrils are a bit too far to the sides and don't really reflect where the nostril holes would have been on a real hadrosaur skull.  The overall body shape is clearly based on the actual skeleton, but also is a bit too skinny, exemplifying the "shrinkwrapped" look many dinosaur reconstructions of the 90s and early 2000s had.  We now know these kinds of dinosaurs would have been much meatier in life especially in the neck and tail regions.  Overall, however, the statue is pretty awesome.  I like the skin texture that was put into it, including the scallop-shaped ridges going down the back and the folds where the neck meets the shoulders.  I also like its sense of movement.  It's not too crazy, but it doesn't look like it's just sitting there doing nothing either.  Despite its inaccuracies, it's very lifelike.

Hadrosaurus statue in the middle of downtown Haddonfield.  A bit outdated by today's standards, it is still a decent representation of the animal.

You can tell from the proportions and even by the fingers and toes that a real hadrosaur skeleton was carefully referenced when this statue was being made.  I just wish it had an actual beak.

My next stop was only about a mile away down the road to the actual site where the Hadrosaurus bones were discovered.  When most people envision a paleontology dig site, they picture an arid desert.  America's first dinosaur, however, was discovered in a heavily forested riverbed.  Since its discovery in the 1800s, the area was taken over by suburbs, but the actual site is still there and marked at the end of a quiet dead end flanked by houses.   When you first pull up, there is a picnic table with an army of plastic dinosaur toys which I'm assuming are for the public to steal play with.  There is a large information sign with a diagram of Hadrosaurus' known skeleton, some information about its discovery, and a beautiful little plaque on a rock commemorating the area.  Then there is a steep, ivy-covered hill that leads into a shallow creek bed where the bones were found!

The site as you pull up at the end of a quiet residential culdesac.

There is a picnic table with toy dinosaurs for me kids to play with at the site.  I recognized the Brontosaurus from Tyco's 1990s Definitely Dinosaurs line, as well as "Bruton", the Iguanodon from Disney's movie from 2000, Dinosaur.  

The plaque on the rock in the middle of the site has what looks like a tiny version of the statue in the downtown area.

It's a far shot from the big scorching desert sites we are used to imagining today, but this is how dinosaur paleontology in the United States began.  I think the memorials reflect it perfectly: peaceful, quiet, modest, but nevertheless an extremely important moment in history that would forever change the way we look at our earth's past, and the animals that lived there.

Just past the plaque there is a steep hill that leads down into a creek in the forest below, where the Hadrosaurus bones were discovered in the 1800s that would spark the American Dinosaur craze that persists to this day.

If you're ever in central New Jersey, come visit Haddy's site.  It's a quiet, peaceful pilgrimage every dinosaur fan should make!

Metriacanthosaurus: Beast of the Week

This week we will be checking out a mysterious European meat-eater, Metriacanthosaurus parkeri!

Metriacanthosaurus was a meat-eating dinosaur that lived in what is now England, during the middle Jurassic Period, about 160 million years ago.  Unfortunately this dinosaur is only known from scant remains, but its overall adult size would have been somewhere between twenty five and thirty feet from snout to tail, judging by the bones we do have.  The genus name translates to "Moderately-spined reptile".  This is because its back vertebra were taller than most other theropods known at the time, but still shorter than those of certain other dinosaurs, like Acrocanthosaurus or Spinosaurus.  As it turns out, The neural arches on Metriacanthosaurus weren't really that unusually tall for a theropod as more different kinds of dinosaurs were unearthed over the years. 

Life reconstruction of Metriacanthosaurus in watercolors by Christopher DiPiazza.  This is mostly speculation.

Sadly, Metriacanthosaurus is only known from a partial skeleton, including part of the pelvis, some vertebra, and part of the leg.  However, this was certainly enough for paleontologists to identify it as a kind of large carnivorous dinosaur.  At the time, in the 1920s, Megalosaurus was the closest known relative so Metriacanthosaurus was lumped with it.  As years went on, and a greater variety of theropod dinosaurs was found and there were more specific anatomical characteristics to compare, Metriacanthosaurus was placed in its own family.

Drawings of Metriacanthosaurus' vertebra and hip bones from Walker's 1964 paper.

Sadly, Metriacanthosaurus' skull was never found, but based on the bones we do have of it, as of now it is considered most closely related to other large meat-eating dinosaurs within its family, called metriacanthosauridae. Most notable are two Chinese dinosaurs, called Yangchuanosaurus and Sinraptor.  If it was anything like its closest relatives, Metriacanthosaurus would have had a relatively short and deep skull, with proportionally long, backwards-curving teeth, ideal for tackling large prey, like other kinds of dinosaurs.

References

Walker, Alick D. (1964). "Triassic reptiles from the Elgin area: Ornithosuchus and the origin of carnosaurs". Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences. 248: 53–134. 

von Huene, F. (1923). "Carnivorous Saurischia in Europe since the Triassic". Bulletin of the Geological Society of America. 34: 449–458.

Naish, Darren; Martill, David M. (2007). "Dinosaurs of Great Britain and the role of the Geological Society of London in their discovery: basal Dinosauria and Saurischia". Quarterly Journal of the Geological Society. 164: 493–510.

Vaderlimulus: Beast of the Week

Today we will be looking at an invertebrate who's lineage is ancient even compared to the dinosaurs.  Let's check out Vaderlimulus tricki!

Vaderlimulus was a prehistoric horseshoe crab that lived in what is now Idaho, USA, during the early Triassic Period, about 245 million years ago. (But I should note that horseshoe crabs in general go back over 400 million years!) The specimen on the fossil record measured about four inches long, and like horseshoe crabs today, was likely a scavenger, feeding on dead organic material that sinks to the bottom of whatever watery habitat it was living in.  The genus name translates to "Vader horsehoe crab" after Darth Vader from the Star Wars franchise.  It was named this way because the unique shape of the creature's shell resembles the sides of Darth Vader's famous helmet.

Vaderlimulus tricki life reconstruction by Christopher DiPiazza.

Vaderlimulus' claim to fame is its amazingly-shaped front portion of its shell, which was extremely wide and tapered into a backwards-facing point on each side.  It's uncertain why the animal evolved this way?  Horseshoe crabs today use their wide, rounded front shells to help stabilize themselves as they trek muddy or gravelly bottoms of the brackish and salt water habitats they live in.  The wide shells make them less likely to flip over if a strong current hits them or if they bump into a rock or something too hard.  Even if they do get flipped, they can arch their backs and use their stiff tails (which are not weapons by the way) to help them flip back over.  We know Vaderlimulus lived in what was at the time a partially freshwater environment, so maybe there was a more consistent or stronger current that would have required it to be more stabilized with the wider shellgear.

Like all horseshoe crabs, Vadelimulus had two compound eyes on the top of its shell, and likely had a series of tiny, barely noticeable eyes around the perimeter of the front of its shell.  Under that first body segment, it had ten legs, armed with small pinchers for picking up tiny morsels to eat.  In the center of those legs it would have had a small mouth.  The segment following the front part housed the shingle-like gills on the ventral side, followed by the stiff tail.  Horsehoe crab tails, like stated earlier, are primarily for stabilization, and are not dangerous at all.

Specimen of Vaderlimulus tricki currenly housed at the New Mexico Museum of Natural History and Science.

Like its modern relatives, Vaderlimulus, probably walked onto land to breed.  When modern horseshoe crabs do this today, the females lay their tiny green eggs in the sand and the males fertilize them.  Males often grab hold of the back end of the females with specialized front legs that look like boxing gloves with hooks, in an effort to fertilize the eggs as soon as they are released.  Because of this, females are larger than the males so they can be strong enough to carry their smaller partners as they move around in the surf.  It also helps to have a larger body to produce as many eggs as possible.

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


References

Allan J. Lerner et al. 2017. First fossil horseshoe crab (Xiphosurida) from the Triassic of North America. Neues Jahrbuch für Geologie und Paläontologie 286 (3): 289-302; doi: 10.1127/njgpa/2017/0702