28 June 2016

It Came From Dinovember III: The Dinosaur Drawings That Would Not Die

Never fear, Raven Lunatics, Noah's Ravens is back from another totally unplanned and largely unnecessary hiatus. Before we dive into new material around these here parts, it's high time I finished up my Dinovember recap, a shameful seven months after the actual event. Without further ado...

Ugrunaaluk kuukpikensis doesn't seem to mind the snow.
[by the author]
Day 21: Ugrunaaluk kuukpikensis - A duckbill (hadrosaur) from the Late Cretaceous Alaskan Arctic, Ugrunaaluk was a close relative of the better-known Edmontosaurus and for a while was thought to be a northerly species of it. My drawing represents a juvenile nearing adulthood, as most specimens of this dinosaur are youngsters. I depicted it with the beginnings of a rounded soft-tissue 'cockscomb' head crest, recently identified in a specimen of Edmontosaurus regalis. However, I now think this was probably not a good decision, for reasons I will discuss in a near-future post. Stay tuned.

Brow horns? Vagaceratops irvinensis don't need no stinkin' brow horns!
[by the author]
Day 22: Vagaceratops irvinensis - Vagaceratops was part of the group of horned dinosaurs called Chasmosaurinae. This is the group containing most of the 'three-horn' type dinosaurs that had a horn on the nose and one over each eye. Not all of them had such an arrangement - Vagaceratops, as you can see, had only a nose horn. Its fancy head frill, however, had several downward-orientated spikes along the top edge. Very handsome, wouldn't you say? Not sure it's proportioned very well, sigh.

Wuerhosaurus homheni wonders if its plates are tall enough.
[by the author]
Day 23: Wuerhosaurus homheni - While most of the plate-backed, spike-tailed stegosaurs lived during the Jurassic Period, Chinese Wuerhosaurus was one of the very last of them, existing near the middlish part of the Cretaceous Period. Since Wuerhosaurus is one of only a handful of dinosaur genera to begin with 'W' it's often featured in kids' books; in those depictions it generally is shown with low, rectangular plates that are quite different to the famous kite-shaped plates of Stegosaurus. It turns out, this plate shape was misinterpreted from a broken fossil. While the plates had wide bases, their whole shape is a mystery - I went with largeish, rounded plates in my interpretation. 

Xiaotingia zhengi sits on a tree limb, content with being small and
feathery, regardless of its exact classification among Paraves.
[by the author]
Day 24: Xiaotingia zhengi - Exactly what sort of creature little Xiaotingia is has yet to be determined. It's some sort of small maniraptoran... but it's been variously proposed to be a dromaeosaur, a troodontid, a bird, or an early relative close to the ancestry of two or all three of these groups. This goes to show you just how birdy many non-bird dinosaurs are; sometimes it can be hard to tell if they are even non-bird dinosaurs.

Blood stains the jaws of a burly Yangchuanosaurus shangyouensis,
one of the biggest predators of the Jurassic Period.
[by the author]
Day 25: Yangchuanosaurus shangyouensis - A carnosaur from China, Yangchuanosaurus was one of the biggest killers of its time, growing up to 10.8 m (35.4 ft) in length. Like many of the big meat-eating dinosaurs, the skull of Yangchuanosaurus was ornamented by a median ridge on the snout and horns in front of the eye sockets. I wanted to focus on this impressive head. I additionally wanted to show what a menacing creature it must've been, and add a somewhat scary element that had a bit more quiet dignity than awesomebro roaring and gaping and slobbering everywhere, hence the drippy, blood-stained mouth as it just looks at you.

Nose horn? Zuniceratops christopheri don't need no stinkin' nose horn!
[by the author]
Day 26: Zuniceratops christopheri - One of the first horned dinosaurs to possess proper horns, Zuniceratops lived in New Mexico around 91 million years ago. It's an impressive-looking animal, with its big frill and long brow horns, but at only around 3 m (9.8 ft) long would be dwarfed by later relatives such as the giant Triceratops. Understanding the evolutionary origins and relationships of Zuniceratops will help scientists better understand the evolution and radiation of the Ceratopsidae, the 'advanced' horned dinosaurs, a group that is almost exclusive to Western North America during the last 15 or so million years of the Age of Reptiles.

Rapetosaurus krausei glances at the viewer as it makes
stately strides across the dry plains of Madagascar, which come
complete with an exceedingly Paulian low horizon line.
[by the author]
Day 27: Rapetosaurus krausei - Madagascar has always had a pretty interesting cast of ecological characters. Back during the end days of the Age of Reptiles, the sauropod Rapetosaurus was one of them. This sauropod lived in a climate that appears to have been very hot and prone to long droughts. It belonged to a group of sauropods called titanosaurs, which often sported chunks of bone called osteoderms on their skin. These osteoderms were generally thought of as being protective armour that covered a titanosaur's scaly hide, but the paucity of osteoderms in Madagascar, and the fact that many of them had hollow internal cavities that would have compromised their strength against a predator's jaws, suggest a different function, at least for some titanosaurs. 

Instead of covering the body like a suit of armour, these very large osteoderms appear to have been a resource store for Rapetosaurus, not unlike the humps of camels. To fuel their huge bodies' demand for the minerals necessary for skeletal growth and making eggshell during hard times of drought, the animals would draw from the mineral content of these big bony chunks. As Rapetosaurus aged, the osteoderms were hollowed out from this process, explaining the interior hollows observed in many of them. The rarity of osteoderms suggests that each individual may have only had a few big osteoderms instead of a covering; I've arranged them here along the top of the tail. In my drawing the big, round osteoderms are shown as the base of a larger conical spike, which is a hypothesis I recall reading about but now am unsure as to where... anyone?... 

Winter is coming, but Leaellynasaura amicagraphica is ready:
 it's got a built-in scarf in the form of its tail, and it also knows
that being extremely cute is helpful in any survival situation.
[by the author]
Day 28: Leaellynasaura amicagraphica - Having already featured two dinosaurs from the North Polar regions, Nanuqsaurus and Ugrunaaluk, I wanted to draw one from the South Pole too. Leaellynasaura is a small ornithopod plant-eater from Dinosaur Cove, in southern Australia which, about 110 million years ago, would have been situated well within the Antarctic Circle. Its big eyes helped it see in the dark and - if it was covered in fluffy feathers as it's shown here and in many other reconstructions - its really long, flexible tail would have been useful for wrapping up in to stay snuggly and warm. 

Well, that was all well and good until this morning, at least, when I found this paper which explains that a sedimentological reappraisal of the Dinosaur Cove site casts into doubt whether all of the material assigned to Leaellynasaura is, in fact, from that animal or actually represents a few different sorts of new ornithopods whose remains were merely deposited together over time, rather than being associated in life. Science marches on, as they say.

Zalmoxes robustus has eaten all the pies.
[by the author]
Day 29: Zalmoxes robustus - In the immortal words of swingin' (Tetzoo Pod)cat John Conway, rhabdodontids are 'little fatties' ('they ate all the pies, you just know it!') and I would have felt remiss if I did not include one of these peculiarly-shaped porkers in my Dinovember lineup. Relatives of the far bigger Iguanodon, rhabdodontids like Zalmoxes are predominantly smallish and European, although the weirdo Muttaburrasaurus langdoni appears to have a place either within or very near this group, and it's a 9 m (29.5 ft) giant and Australian! Zalmoxes here is from Romania, and at a much more manageable 2 m (6.6 ft) long, I can't help imagining that these tubby herbivores would have made for rather nice pets. Zalmoxes hails from an environment that would have, during the Late Cretaceous, been an island populated by 'dwarf' dinosaurs whose more compact body size was an adaptation to limited resources found in a smaller area. This fauna was famously discovered and studied by pioneering palaeontologist Franz Nopsca, the gay dinosaur baron of Transylvania, one of the most interesting characters in the annals of palaeontology. I'd love to write about Nopsca myself someday but until I can, take a look at this excellent piece by Asher Elbein over at Love In the Time of Chasmosaurs.

Plateosaurus engelhardti hopes you like its funny-shaped skull and
its spiny midline crest, which is both fetching
and speculative.
[by the author]
Day 30: Plateosaurus engelhardti - It was the final day of Dinovember, and panic set in. I'd drawn 29 dinosaurs. Some of the results I was very pleased with, and some (maybe a few too many) I thought fell a little short of my ambitions. But there was a major problem. All 29 dinosaurs were from either the Jurassic or Cretaceous Periods. I had one day left and hadn't done a single dinosaur from the Triassic, the period in which dinosaurs first appeared! 

To rectify this horrid crime, I drew a dinosaur I've always rather liked and have come to appreciate even more lately, Plateosaurus. This is a really well known animal, with thousands of specimens from all stages of life having been discovered across Europe. A bipedal relative of the later sauropods, Plateosaurus could grow as much as 10 m (33 ft) long, making it one of the biggest land animals ever to have lived by the time it existed, around 210 million years ago. The wealth of Plateosaurus fossils recovered means that we are able to study many aspects of this dinosaur's biology that are impossible to research for most fossil creatures. 

So that's a long-overdue wrap on Dinovember. Coming up: Brontosaurus revisited, video games, and what to call a duckbilled dinosaur. Stay tuned for more regular updates in the coming weeks.

-- M

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