Eukritta- Beast of the Week

 This week we will be checking out a beast that is named after one of the most iconic movie monsters.  Watch out for Eucritta melanolimnetes!

Eucritta was an early tetrapod (animal with four limbs or that evolved from a four limbed ancestor...basically any vertebrate that's not a fish) that lived in what is now Scotland during the Carboniforous period, between 344 and 331 million years ago.  It measured about 10 inches (25.4cm) long from snout to tail and would have been a meat-eater when alive.  The genus and species name together, Eucritta melanolimnetes, translates to "True Creature from the Black Lagoon", after the famous 1954 monster movie.  This is in reference to how, like the movie monster, Eukritta exhibited features from multiple different kinds of other animals and would have spent time on both land and in the water when alive.

Life reconstruction of Eucritta in watercolors by Christopher DiPiazza.

When Eucritta was alive, none of the land vertebrates we are familiar with today were around yet.  The ones that did exist would have had the most in common with modern amphibians but were still pretty different even from them.  Eucritta stands out among these ancient animals because it possessed a number of features associated with multiple different varieties of early land creatures that were evolving around that time, placing it somewhere between the early ancestors of the first reptiles and the amphibian-like temnospondyls.  

Eucritta is known from several skeletons so we actually know quite a bit about its anatomy.  It possessed a wide, semi-circular skull and its eye sockets were proportionally large and round, suggesting it had good vision in life, and it possessed many small pointed teeth, ideal for grabbing and swallowing small prey.  The top of its mouth also possessed small tooth-like protrusions, which would have helped ensure live prey did not escape once grabbed.  Despite its amphibian-like skull, it also possessed a bony pallet on the roof of its mouth separating its mouth from its nose, which is something amphibians do not have, but an ancestral trait to the group of animals that would become the first reptiles.  It's arms were short and robust, and its legs were proportionally longer and also powerfully built, suggesting that Eucritta could have spent considerable time walking around outside the water.  Sadly its tail was never found so we do not know if it was stubby or longer and possibly paddle-shaped to aid in swimming. 

Photograph of the skull and shoulder girdle of Eucritta from the paper by Clack et. al. referenced below.

Eukritta's low flat skull and short, straight ribs, give us clues as to how it breathed.  Modern ampbibians, like frogs and salamanders have the same traits and get their oxygen by buccal pumping, which is when they use muscles in their throat to pump air into their bodies. (Ever notice how the skin under a frog's chin is always moving up and down? that's buccal pumping in action.)  This is because they do not have a diaphragm, a muscle which other land animals (including us) use to breathe instead. Animals with diaphragms also have longer ribs that curve around their torso to better support their organs. 

References

Clack, J. A. (March 2001). "Eucritta melanolimnetes from the Early Carboniferous of Scotland, a stem tetrapod showing a mosaic of characteristics". Earth and Environmental Science Transactions of the Royal Society of Edinburgh. 92 (1): 75–95.

Clack, Jennifer A. (2 July 1998). "A new Early Carboniferous tetrapod with a mélange of crown-group characters". Nature. 394 (6688): 66–69.

Garudimimus: Beast of the Week

This week we're checking out a feathered dinosaur that helps us understand the evolution of the "bird mimic" family of dinosaurs.  Enter Garudimimus brevipes!

Garudimimus was a theropod dinosaur that lived in what is now Mongolia during the Cretaceous period, between 96 and 89 million years ago.  From beak to tail it would have measured about 11.5 feet (3.5 meters) long and it likely would have been an omnivore when alive.  The genus name translates to "Garuda Mimic", in reference to Garuda, the half bird half human Hindu deity.  The species name, brevipes, translates to "short foot".

Watercolor life reconstruction of Garudimimus by Christopher DiPiazza.

Garudimimus was a member of the ornithomimosaur family of theropod dinosaurs that are famous for resembling ostriches while not being directly related to them, rather evolving a similar body plan independently millions of years prior.  Garudamimus is interesting because it can be considered a transition fossil, possessing characteristics of both older and more recent relatives of this family, and thus helping us understand how this group evolved.  Earlier members of the ornithomimosaur family, like Harpymimus, are known for having teeth and still possessing four toes on each foot, the first of which was very short and probably had no purpose, like the dewclaw on a dog.  Later living members, like Ornithomimus and Struthiomimus, had much longer, more slender limbs, with only three toes per foot and toothless beaks.  Garudimimus possesses a mix of these traits, having a stockier build with the vestigial fourth toe on each foot, but also a toothless beak.  Many paleontologists currently believe that Garudimimus is actually more closely related to the extremely large and unusual member of the ornithomimosaur family, Deinocheirus.    

Skull of Garudimimus on display at the Mongolian Natural History Museum.

Garudimimus' skull had a relatively narrow beak with a weak bite force, even compared to other ornithomimosaurs, suggesting it was more specialized to eating plants.  The sides of its beak had a sharper edge which may have helped it cut bite-sized pieces of leaves as it ate.  Its eye sockets were proportionally huge and round, implying it had a strong sense of sight and its neck would have been long and flexible, which would have been helpful for looking out for potential predators.  Some experts have suggested Garudimimus would have been active at night, but having large eyes doesn't always reflect a nocturnal lifestyle. (modern ostriches are a good example of this)

Garudimimus' legs were proportionally shorter and stockier than those of its later relatives, but it still would have been comparably fast, especially compared to other dinosaurs in its environment, likely relying on speed to avoid predation.  Like all members of its family it likely would have had feathers in life, which would have aided in regulating its body temperature, caring for eggs and young, and possibly for display within its species.  

References

Barrett, P. M. (2005). "The diet of ostrich dinosaurs (Theropoda: Ornithomimosauria)". Palaeontology. 48 (2): 347−358.

Hughes, G. M.; Finarelli, J. A. (2019). "Olfactory receptor repertoire size in dinosaurs". Proceedings of the Royal Society B. 286 (1904) 20190909.

Kobayashi, Y.; Barsbold, R. (2005). "Reexamination of a primitive ornithomimosaur, Garudimimus brevipes Barsbold, 1981 (Dinosauria: Theropoda), from the Late Cretaceous of Mongolia" (PDF). Canadian Journal of Earth Sciences. 42 (9): 1501−1521.

Kurumada, Y.; Aoki, S.; Aoki, K.; Kato, D.; Saneyoshi, M.; Tsogtbaatar, K.; Windley, B. F.; Ishigaki, S. (2020). "Calcite U–Pb age of the Cretaceous vertebrate-bearing Bayn Shire Formation in the Eastern Gobi Desert of Mongolia: usefulness of caliche for age determination". Terra Nova. 32 (4): 246−252.

Schmitz, L.; Motani, R. (2011). "Nocturnality in Dinosaurs Inferred from Scleral Ring and Orbit Morphology". Science. 332 (6030): 705−708.

Muttaburrasaurus: Beast of the Week

 This week we will be checking out a mysterious plant-eating dinosaur that called what was once Australia home.  Enter Muttaburrasaurus langdoni!

Muttaburrasaurus was a plant-eating dinosaur that lived in what is now Northern Australia during the early to middle Cretaceous period, between 103 and 113 million years ago.  From snout to tail it measured about 23 feet (7m) long.  Its name translates to "Muttaburra Reptile/Lizard" in reference to the part of Queensland in Australia where its fossils were first found. 

Muttaburrasaurus life reconstrucion in watercolors by Christopher DiPiazza.

Muttaburrasaurus would have stood on powerful hind legs, and possessed short but strong arms. It likely normally walked on two legs but would have been capable of dropping down to all fours at times if it wanted.  Scientists were able to predict this not only based on the proportions of its limbs, but also the shape of it's inner ear bones, which often can indicate an animal's posture and preferred head orientation.  

Skeletal mount of Muttaburrasaurus on display at the National Museum of Australia.

Muttaburrasaurus had a relatively long neck and proportionally small head with a snout was originally thought to have ended in a tall crest, similar to those of some hadrosaurs, but it was more recently found, thanks to finding additional missing parts of its skull, that it actually had a rather pointed, narrow snout with a bony bulge midway up the nose, making it much more unique looking.  We still don't know the exact purpose of this feature.  It probably had something to do with display within the species.  Others have suggested it perhaps had something to do with the dinosaur possessing salt glands to help it eat plants that grew in ocean water near where it lived.

Remember putting a plastic cup over your mouth as a kid?  It looks like that.

The back of Muttaburrasaurus' jaws were lined with leaf-shaped teeth for slicing through plants.  Unlike its distant relatives, the hadrosaurs, these teeth were arranged in a single row in each jaw with the new replacement teeth growing directly from below.  Muttaburrasaurus also possessed teeth at the very front of its snout, which is actually rare among ornithopod dinosaurs, notably also present in Thescelosaurus. (which it was also maybe closely related to?)  Like all ornithopods, the tip of its snout was a beak, which would have been for clipping vegetation. 

Skull of Muttaburrasaurus (missing the tip of the snout) (Photo courtesy of Alcharinga Journal of Paleontology.)

The environment Muttaburrasaurus would have lived in was near an ocean coast and would have been seasonally cold.  This is because during that part of the Cretaceous, Australia was much further south and still attached to Antarctica.  Some experts suggest Muttaburrasaurus may have even been adapted to eat plants and algae that grew in salt water, possibly as a food source during the colder months when other plants were more scarce.

Muttaburrasaurus was a member of the ornithopod group of dinosaurs, most famous for including distant relatives like Iguanodon and the "duck-billed" hadrosaurs.  Its identity within this group has proven to be more difficult to pin down.  It was originally considered a close relative of Iguanodon and was even reconstructed with thumb spikes to reflect this. Other experts have since suggested  it was more closely related to dinosaurs like Camptosaurus, and others more to the big-headed rhabdodontid family, like Zalmoxes. (The taxonomy of ornithopod dinosaurs is currently very complicated and tends to change as we discover more fossils.)

References

Bartholomai, Alan and Molnar, R.E. (1981). "Muttaburrasaurus: a new Iguanodontid (Ornithischia:Ornithopoda) dinosaur from the Lower Cretaceous of Queensland". Memoirs of the Queensland Museum. 20 (2): 319–349.

Herne, M. C.; Bevitt, J. J.; Milan, L.; Hocknull, S. A.; Tait, A. M.; Allen, C. M.; Rozefelds, A. C.; Molnar, R. E.; Weisbecker, V.; Bell, P. R. (2026). "Cranial anatomy, palaeoneurology, palaeobiology and stratigraphic age of the large-bodied ornithopod, Muttaburrasaurus langdoni Bartholomai and Molnar, 1981, from the mid-Cretaceous of Australia". PeerJ. 14 e20794.

Molnar, Ralph E. (1996). "Observations on the Australian ornithopod dinosaur, Muttaburrasaurus"". Memoirs of the Queensland Museum. 39 (3): 639–652.

Arundelconodon: Beast of the Week

 This week we will be looking at a unique mammal that lived alongside some of the largest dinosaurs!  Check out Arundelconodon hottoni.  

Arundelconodon was a small mammal that lived in what is now Maryland, in the United States, during the early Cretaceous Period, about 115 million years ago, making it one of the oldest known mammals from the east coast of the US.  It is estimated to have measured about eight to ten inches (20-25cm) long from nose to tail, roughly the same size as a rat.  Based on the teeth it would have been a meat-eater when alive.  It's genus name translates to "Arundel Cone Tooth" after the county in Maryland the location of its fossils is name after.  The species name is in honor of paleontologist, Nicholas Hotton.  

Despite its size Arundelconodon may have attacked larger animals, like this Aquilops, a roughly housecat-sized dinosaur.

Mesozoic mammal fossils are generally extremely difficult to find because the animals they would come from tended to be small and therefore delicate and unlikely to fossilize well.  When they do preserve, it is usually in the form of their teeth, which are made of more durable material, called enamel, than bones.  Luckily teeth are also extremely diagnostic for mammals, so scientists can deduct at least the group of mammals a tooth belongs to most of the time even with no other parts available. Based on teeth and jaws, Arundelconodon was identified as a member of the family of mammals called the triconidontids.  This was a now extinct group of mammals that flourished during the Jurassic and Cretaceous periods that are identified by having three distinct cone-like points on their molars. (The name even translates to "three cone tooth")  Triconidontids would have branched off the mammal family tree relatively early in their history, being more ancient than the first placental mammals but more recent than monotremes.  Because of this it is thought that they birthed live young instead of laying eggs, but little else is currently known about their reproduction, like if they kept their young in a pouch, like marsupials.  Like all mammals, however, they would have produced milk for their young.

Jaw and teeth of Arundelconodon.  This entire fossil is about 1cm long. Image from the Prince George County website.

The teeth of Arundelconodon were notably long compared to the jaw.  The three prongs on the molars were also arranged in a single line, and would have self-sharpened against the teeth of its upper jaw as it opened and closet its mouth.  It is because of this that we are almost certain it was a meat-eater in life.  It may have specialized in hunting small prey, like insects, but it also may have even been able to take down larger prey similar to how certain mammals, like weasels and shrews do today.  It is interesting to imagine Arundelconodon possibly attacking small or baby dinosaurs!

Like most mammals of the Mesozoic, it is likely Arundelconodon was nocturnal or crepuscular (active at dawn and dusk) to avoid predatory dinosaurs, many of which were likely diurnal.  During the day it may have spent time hiding and sleeping underground or maybe even in trees.  It would have needed to look out for predators like the sickle-clawed, Deinonychus and the several different kinds crocodilians that are known from the same fossil site.  The extremely large meat-eating dinosaur, Acrocanthosaurus, also probably would have posed a threat to Arundelconodon when it was a juvenile. (As an adult it may not have noticed it altogether.) Other dinosaurs Arundelconodon would have coexisted with were the small ceratopsian, Aquilops, the sauropod, Astrodon, and the extremely large armored dinosaur, Priconodon.   

References

Celik, Mélina A.; Phillips, Matthew J. (8 July 2020). "Conflict Resolution for Mesozoic Mammals: Reconciling Phylogenetic Incongruence Among Anatomical Regions". Frontiers in Genetics. 11: 0651.

Cifelli, Richard L.; Lipka, Thomas R.; Schaff, Charles R.; Rowe, Timothy B. (1999). "First Early Cretaceous Mammal from the Eastern Seaboard of the United States". Journal of Vertebrate Paleontology. 19 (2): 199–203.

Luo, Zhe-Xi; Kielan-Jaworowska, Zofia; Cifelli, Richard L. (2002). "In quest for a phylogeny of Mesozoic mammals". Acta Palaeontologica Polonica. 47 (1): 1–78.

Yi: Beast of the Week

 This week we will be checking out a dinosaur that was so unusual, it completely changed what we thought we knew about dinosaur evolution.  Check out Yi qi! (pronounced "EE-chee")

Yi was a small theropod dinosaur that lived in what is now Hebei, in Northeastern China during the late Jurassic period, about 159 million years ago.  From snout to tail it only measured about a foot (30 cm) long and its wingspan was about 2 feet (60cm) wide.  The genus came, "Yi" translates from Mandarin to "wing" and the species name, "qi", means "strange", which is totally appropriate as you are about to find out.  It also fun to note that Yi qi has the shortest full name of any dinosaur.

Watercolor reconstruction of Yi by Christopher DiPiazza.

Yi belonged to the family of theropod dinosaurs, called scansoriopterygidae, which are known for being relatively small, with short snouts and teeth in the front of their jaws that jutted forward, possibly an adaptation for grabbing insects.  They are also known for having feathers and extremely long fingers, often portrayed living in trees.  These traits alone make them stand out among dinosaurs, but what makes Yi even more unusual is the fact that it had a sheet of skin stretching from its fingers and down its arms, which was supported by an extra rodlike bone that grew out of its wrist, forming what can only be described as batlike wings.  Before this we only knew of animals evolving wings three times in vertebrates, bats, pterosaurs, and dinosaurs(feathered wings seen in birds).  Now it turns out that dinosaurs evolved a second completely different version of wings alongside the feathered ones thanks to Yi.  It should also be noted that modern gliding mammals, like flying squirrels possess an elongated piece of cartilage near their wrist, extremely similar to the bone growing out of Yi's.  All of these features suggests Yi was likely at least gliding around when it was alive.  The experts who originally described Yi suggested it may have even been capable of powered flight but more evidence is needed to prove it.  

Diagram showing the homologous parts of the wings of each kind of vertebrate.  Thanks to Yi we know dinosaurs evolved wings at least two separate times.

What makes Yi even more interesting is despite having batlike wings, its body was mostly covered in feathers. The feathers themselves were preserved enough to tell they each comprised of a quill with a little tuft at the top, essentially mini palm tree shaped.  They start almost at the tip of the dinosaur's nose and go down the head and neck, cover the torso extending to the arms, and also on the legs down the shins.  Scientists were also able to find melanosomes (organelles that determine pigment in hair, skin, and feathers) preserved in both the feathers and skin of Yi.  According to the melanosome shapes that preserved, Yi may have had reddish colored feathers on its head, gray or black feathers on its body, and dark gray or black colored skin on its wings. (Keep in mind this is only based on the melanosomes they were able to find.  Sometimes animals have a variety of different melanosomes that when together reflect different colors, some that maybe don't preserve well.)

The unusual appearance of Yi doesn't even there. A close relative of Yi's, called Epidexipteryx, was discovered with four long ribbon-like feathers growing out of its otherwise stumpy tail. Sadly Yi's tail wasn't found, but it is possible it also sported feathers like this.  We can't be sure what they would have been for, likely display of some kind if it was anything like its modern bird relatives. 

Photograph of the found fossils of Yi qi from the paper by Xu et al. referenced below.

All of these unusual traits lead most experts to think Yi was a tree dweller in life.  It could have used its strong arms and long fingers to climb, and probably was able to glide at least short distances between branches.  Its short face and small teeth would have been a good for eating insects, but it may have been omnivorous too, nibbling seeds or other plant matter.  The fossils of many other interesting creatures have been unearthed in the same area as Yi, including fellow dinosaurs, Anchiornis, Eosinopteryx, and Tianyulong, the pterosaur, Darwinopterus, as well as the salamander Chunerpeton, to name a handful. 

References

Dececchi, T. Alexander; Roy, Arindam; Pittman, Michael; Kaye, Thomas G.; Xu, Xing; Habib, Michael B.; Larsson, Hans C. E.; Wang, Xiaoli & Zheng, Xiaoting (2020). "Aerodynamics Show Membrane-Winged Theropods Were a Poor Gliding Dead-end". iScience. 23 (101574) 101574.

Xu, Xing; Zheng, Xiaoting; Sullivan, Corwin; Wang, Xiaoli; Xing, Lida; Wang, Yan; Zhang, Xiaomei; O'Connor, Jingmai K.; Zhang, Fucheng & Pan, Yanhong (7 May 2015). "A bizarre Jurassic maniraptoran theropod with preserved evidence of membranous wings". Nature. 521 (7550): 70–73.

Sauroposeidon: Beast of the Week

 This week we will be checking out a huge dinosaur with an equally impressive name.  Enter Sauroposeidon proteles!

Sauroposeidon was a sauropod dinosaur (long neck) that lived in what is now Oklahoma, Texas, and Wyoming, USA, during the early Cretaceous period, about 113 million years ago.  Its genus name translates to "Lizard Earthquake God" after the Greek god, Poseidon, who in addition to his more famous association with the ocean, was also the god of earthquakes in Greek mythology. Since not a full skeleton is known, it is difficult to tell exactly how long this dinosaur could get (because necks and tails vary so much in sauropods) but estimates range anywhere between 89 to 112 feet (27-34 m) long, making it one of the largest land animals to ever exist. 

Watercolor of two Sauroposeidon squaring up by Christopher DiPiazza.

Sauroposaidon was originally known from only a few neck vertebra.  That being said these neck vertebra were enormous, the longest of any dinosaur found in fact.  Just one vertebra alone measured 4.6 feet (1.4m)! Later on more bones, including limbs, more vertebra, and even parts of the skull, which were originally referred to as their own genus, Paluxysaurus, were found to actually the same as Sauroposeidon.  Probably the most interesting bit of information regarding this dinosaur's discovery is the fact that some of its limb bones were initially misidentified as fossilized tree trunks!

Photograph of three neck vertebra from Sauroposeidon. (Photo credit: Mathew Wedel)

Sauroposeidon's neck bones were hollow, like those of a bird, and therefore extremely light for their immense size.  This would allow the dinosaur to more easily move its head and neck around without exhausting itself.  This was likely an adaptation for being able to reach leaves at the tops of trees to eat, but also could have been a way for the dinosaur to access a wide range of food without moving its body, thus conserving energy.  Large sauropods, like Sauroposeidon, likely needed to be eating most of the time they were awake in order to fuel their bodies. 

As an adult, Sauroposeidon likely had not predators to worry about.  As a juvenile, however, it may have been preyed on by Acrocanthosaurus, and as babies, it would have needed to watch out for Deinonychus.  It also coexisted with the tiny ceratopsian, Aquilops, and the long-tailed ornithopod, Tenontosaurus.

References

Rose, Peter J. (2007). "A new titanosauriform sauropod (Dinosauria: Saurischia) from the Early Cretaceous of central Texas and its phylogenetic relationships" (web pages). Palaeontologia Electronica. 10 (2). 

Wedel, Mathew J.; Cifelli, R.L.; Sanders, R.K. (March 2000). "Sauroposeidon proteles, a new sauropod from the Early Cretaceous of Oklahoma" (PDF). Journal of Vertebrate Paleontology. 20 (1): 109–114.

Wedel, Mathew J.; Cifelli, R. L.; Sanders, R.. K. (2000). "Osteology, paleobiology, and relationships of the sauropod dinosaur Sauroposeidon" (PDF). Acta Palaeontologica Polonica. 45: 343–388.

Leptoceratops: Beast of the Week

 Today we will be looking at the small ceratopsian dinosaur, Leptoceratops gracilis!

Leptoceratops was a plant-eating ceratopsian dinosaur that lived in what is now Alberta, Canada, during the late Cretaceous period, between 68 and 66 million years ago.  From beak to tail it measured about 6.5 feet (about 2m) and would have been able to walk on four or two limbs when alive. The genus name translates to "small horned face". 

Leptoceratops life reconstruction in watercolors by Christopher DiPiazza.

Leptoceratops was a ceratopsian dinosaur, which means it possessed a strong parrot-like beak and a bony frill on the back of its skull.  Unlike a lot of its larger relatives it didn't have any horns on the nose or over the eyes, but it did have large pointed jugal (cheek) bones which likely supported horns of some kind in life on the tips.  Its lower jaw was extremely deep, implying there were huge muscles there in life, giving it a powerful bite.  In the jaws it sported leaf-shaped teeth which were proportionally the largest of any ceratopsian.  The wear on Leptoceratops' teeth is unique, suggesting its jaws would  have moved back and forth in a circular motion, similar to many herbivorous mammals, but unheard of in any other dinosaur. This unique feeding style, combined with the raw power of its jaws and the sharpness of the beak, may have allowed it exploit a wider range of plant foods since it did not have the height advantage of other larger plant-eaters it coexisted with.  

Diagram of the tooth ware and chewing motion of Leptoceratops from the paper by Varriale et al. referenced below.

Leptoceratops had proportionally shorter but powerful arms, each armed with five strong fingers, the first three of which had claws.  Its hind legs were longer and it was likely capable switching between quadrupedal and bipedal walking and running depending on what suited it.  The vertebra in its tail had long neural arches, forming a tall almost fin-like profile, which may have been an adaptation for display against rivals of the same species or possibly predators, distorting the animal's profile and making it look larger than it really was.  

Two Leptoceratops skeletons on display at the Canadian Museum of Nature

A paper published in 2019 suggests Leptoceratops may have lived underground, thanks to multiple skeletons of different aged individuals found in what appeared to have been a collapsed burrow.  This doesn't seem impossible since Leptoceratop's extremely short frill wouldn't have gotten in the way if it was moving around through tunnels in life.  Sleeping underground is also a great strategy for avoiding predators.  

Despite its size Leptoceratops may have been able to fend off predators by simply being a jerk.  (This is not backed up by any fossil evidence but behavior rarely is.)

When alive Leptoceratops would have shared its habitat with some of the most famous dinosaurs, like Edmontosaurus, Ankylosaurus, Pachycephalosaurus, and Triceratops. It would have needed to watch out for predators like Acheroraptor, Nanotyrannus, and Tyrannosaurus, plus all the crocodilians and large pterosaurs, like Quetzalcoatlus, that were around. (although Quetzalcoatlus may have only been able to prey on babies.)  At first it's easy to imagine little Leptoceratops as nothing more than fodder for these predators since it had no horns or armor, but keep in mind that beak backed up with all that jaw pressure was potentially a devastating weapon.  It's not supported by any true evidence, but I always imagined Leptoceratops as extremely foul tempered and aggressive, even towards animals that dwarfed it, as a defense strategy. Modern Honey Badgers, Wolverines, and even members of the pig family effectively exhibit this strategy today. Even mighty T. rex couldn't have wanted to endure a bite on the toe from a Leptoceratops beak! 

References

Brown, B. (1914). "Leptoceratops, a new genus of Ceratopsia from the Edmonton Cretaceous of Alberta". Bulletin of the American Museum of Natural History. 33 (36): 567–580.

Fowler, D.W.; Wilson, J.P.; Freedman Fowler, E.A.; Horner, J.R. (2019). "The Horned Dinosaur Leptoceratops (Ornithischia: Neoceratopsia) Raised its Young in Communal Nesting Burrows: Evidence from Three New Bonebeds in the Hell Creek Formation (Maastrichtian, Late Cretaceous), Montana" (PDF). Presented Abstracts. Cretaceous and Beyond: Paleontology of the Western Interior. A Symposium Focusing on Cretaceous and Paleogene Vertebrate Paleontology of the Western Interior. 94. North Dakota Geological Survey. Miscellaneous Series: 20.

Maiorino, L.; Farke, A.A.; Kotsakis, T.; Raia, P.; Piras, P. (2018). "Who is the most stressed? Morphological disparity and mechanical behavior of the feeding apparatus of ceratopsian dinosaurs (Ornithischia, Marginocephalia)". Cretaceous Research.

Ryan, M.J.; Currie, P.J. (1998). "First report of protoceratopsians (Neoceratopsia) from the Late Cretaceous Judith River Group, Alberta, Canada". Canadian Journal of Earth Sciences. 35 (7): 820–826.

Varriale, F.J. (2016). "Dental microwear reveals mammal-like chewing in the neoceratopsian dinosaur Leptoceratops gracilis". PeerJ. 4 e2132.