troodontids

Stenonychosaurus is BACK!! I am ridiculously excited about this.

Why am I so excited about the return of a somewhat-obscure genus of troodontid that hasn’t been a recognised scientific name since the 1980s? Well, I’m glad you asked that weirdly specific question, because I just happen to have an answer.

Stenonychosaurus used to be one of my very favourite dinosaurs when I was a small kid. It was in one of the first dinosaur books I ever owned, and to be honest the main reason I loved it so much was probably because I was proud that I could say its name properly. Cut forwards a couple of years and I find out that Stenonychosaurus has been lumped into Troodon. I was sad, but I got used to it.

And now Stenonychosaurus inequalis has made its glorious return, just as Brontosaurus did before it! And “Troodon formosus” has been shackled with quotation marks and sent to the dungeon of nomen dubium. I probably shouldn’t be this vindictive about the recovery of a species, but I am.

So now you know the tale of my old friend Stenonychosaurus. We are now reunited at last, and shall continue to have many wonderful days together.

At least until another study does something else weird with it, anyway.

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Assorted Djadochta dinosaurs.

(Left to Right, Top to Bottom)

Byronosaurus

Saurornithoides

Gobivenator

Pinacosaurus

Plesiohadros

Protoceratops

Udanoceratops

Velociraptor (V. mangas/Tsaagan at the top, V. mongoliensis at the bottom)

I AM SO ANGRY RIGHT NOW.

I had a dream that I was driving through a snowy, semi-wooded area and I SAW A TROODON.  A literal real-life Troodon, no mistaking it.  It was antagonizing a large deer.  Pretty obviously not hunting it (it was way too small and the deer was very big) just nipping at its rear end for the lulz (I’m amazed it managed to not get kicked.)

And then it ran off and I jumped out of the car like “HOLY CRAP I KNOW WHAT COLOR TROODON IS I HAVE TO GET PHOTOS SO I CAN SHOW PEOPLE.”

Because that was the priority.  I had to prove to people that I knew its real colors, and not that it was ACTUALLY ALIVE or anything.

It was almost all white, aside from some chestnut patches along the face, back, wings, and tail fan. So kiiiinda like sinosauropteryx, just with way more white.

I found myself on this high cliff-like overhang looking down the forest below and saw it running back and forth at the bottom, kind of like it was amusing itself kicking up snow.  IT WAS TOO FAST.  I could not get any decent photos that were not blurry as all hell.

I only had one choice: I had to get closer.

As I approached it I found myself actually considering more serious implications of A REAL-LIFE TROODON, such as how amazing it was that it looked almost unchanged after all this time.  (But then, plenty of theropod lineages kept the same body shape for dozens of millions of years, I reminded myself, so it wasn’t that surprising.)

And I had a moment of doubt, like “maybe I’m wrong and it’s not a Troodon” but then I saw the long tail and the sickle claw and I KNEW.  Also it was waaay too leggy and slender-faced to be a dromaeosaur.  YES.  IT WAS A TROODON.  It was very playful and curious and not nearly as shy as I was expecting (how has no one found you until now wtf.)

Its eyes were SO HUGE and amber-colored and the way the light shined through the cornea and reflected off the iris was incredible (my dreams almost never render things that hi-res, one reason I was certain it was not a dream.) Also as I got closer I was able to see that it actually had a lot of neat darker markings within the chestnut patch around the eyes.  It sort of had a facial disk, although not nearly as exaggerated as owls.

In fact, the detail about it that surprised me the most was that it had no feathers on its feet (there’s snow everywhere!  how are your feets warm??) but rather pebbly white scales with darker slate-grey scutes.  Not that this is impossible–I mean, scutes are derived from feathers, and the switch between them seems pretty variable in anything past the point of Stage IV feathers (i.e. all pennaraptors.)  It just surprised me because I like to draw troodontids with feathered feet and dromaeosaurs without, to distinguish them.  But then again, it’s been 66 million years, modern troodon had to be pretty derived, even if they still had the same general shape.

Also living Troodon means that the crown group for birds suddenly == Eumaniraptors!  Hahahaha dromaeosaurs are birds now, suck it dudebros.

But THE WORST PART was that the dream had a fake-out ending!  I woke up like “oh no, oh no, do I still have the photos” I and I frantically checked my phone and YES I STILL HAD THE PHOTOS ok everything was good, so I went back to sleep feeling confident.

…I didn’t really have the photos. >:(

Prince Creek

Watched by a foraging troodontid, a herd of Arctic hadrosaurs walk along a moonlit beach in Alaska, 69 mya.

Inspired by trackways left in volcanic ash at Prince Creek. The species depicted have unclear status at this moment in time, so let’s call them Troodon sp. and Ugrunaaluk kuukpikensis/Edmontosaurus regalis.

A simple droman ontogeny chart

Child - Feather coat scruffy and downy.  Pennaceous feathers haven’t fully grown in yet.

Adolescent - Pennaceous feathers have grown in and arms are disproportionately long for the body.  Adolescents are capable gliders and tend to use their feet for holding things.

Adult - Feathers have receded from the fingertips, freeing up the hands for tool use.  Display feathers around face are fully developed and will be brightly colored.  Gliding ability reduced.  Using feet to hold things at this age is considered childish (but everyone still does it anyway when no one is looking.)

The Ovi: An exercise in speculative evolution…

I’ve been thinking for a while about what might have arisen if the dinosaurs hadn’t gone extinct, and if selective pressures were such that higher intelligence evolved. There have been some popular works on the subject over the years (the classic and extremely human-like “dinosauroids” of Dale Russell, Robert J. Sawyer’s “Quintaglio Ascension” trilogy of sci-fi books, and many other artists working on similar projects); this one is my take on the idea - sentient Oviraptorosaurs.

It seems most other similar projects tend to speculate on elevated cleverness evolving in the Paraves clade, and this makes sense: We know some of the most intelligent extant organisms on Earth (outside of the primates) are birds, especially the crows and ravens, and certain parrots. Some of their closest extinct non-avian dinosaur relatives are the Dromaeosaurids and Troodontids, and these fine animals are popular points of departure for speculative evolutionists. The Maniraptoran clade (of which Dromaeosaurids, Troodontids, modern birds, and Oviraptorosaurs are all a part) has some key attributes that we share: On Earth we have only one data point for human-level intelligence so far, so it seems logical to me to look for other organisms with similar traits when speculating on potential evolution of advanced tool-using intelligence – traits like large brains, high brain to body size ratios, grasping appendages (useful for manipulating the environment), bipedal motion (to keep those grasping appendages unoccupied), living on land (as smart as dolphins are, it would be hard to use fire, smelt metals etc. underwater), and a social structure that puts selective pressure on the ability to out-think and/or cooperate with others of your species.

Personally, I favored the Oviraptorosaurs in part to differentiate my own fiction from the rest. Oviraptorosaurian brain/body ratio may not have been quite as high as that found in the Troodontids, for example, but they do have one additional interesting trait that is similar to our own hominid forebears: probable omnivory. It seems to me that hominid and corvid intelligence may be at least partly linked to social interaction with conspecifics, but also with problem-solving to exploit different food resources. The Dromaeosaurs and Troodontids, it seems, were more likely obligate carnivores and thus would have less evolutionary pressure to develop interesting techniques for obtaining food. That, and I think Oviraptorosaurs look really cool.

This is a work of fiction; I was thinking of potentially writing and illustrating a book on the subject. If you’d like to see more, leave a comment!

Please do not use or reproduce without permission.

takingturnsatrandom  asked:

What do you think about the "dinosauroid" speculative model for troodontid evolution

I’ve talked a little bit about the dinosauroid before on this blog, but now I’m going to give you a much more specific and detailed answer.  The short answer, for those who don’t like reading, is “It sucks.”

For those of you who want the long answer:

In 1982, a Canadian paleontologist named Dale Russell reconstructed the above creature - a hypothetical sentient dinosaur, which he dubbed “the Dinosauroid”.  He conjectured that, had the Cretaceous extinction never happened, some dinosaurs might have gone on to evolve humanlike intelligence.  Russell’s candidate for the dinosaur most likely to develop sentience was Stenonychosaurus (now known as Troodon), a dinosaur known for its big brain.

Russell developed a relative well-thought-out conceptualization of dinosauroid biology.  He speculated that the Dinosauroid would give birth to live young, but would feed them in a birdlike fashion, due to its lack of mammary glands.  He also speculated that it would have a large, human-like brain, with proportionally larger eyes in the fashion of its troodontid ancestors.

This is stupid.

  • First of all, Troodon may not have been as intelligent as we thought.  While troodontids did have the largest brains relative to their body sizes of all dinosaurs (excluding modern birds), it’s debatable how much this would have contributed to their intelligence.  My personal theory, based on the anatomy of troodontid eyes and ears, is that they filled a similar niche to modern-day owls - nocturnal predators that hunted with sight and hearing - and that their large brains were focused on processing sensory input, rather than having a particularly advanced capacity for creative intelligence.
  • Secondly, Dale Russell’s dinosauroid is anthropocentric to a disagreeable degree.  Russell’s contemporaries criticized him for his vision of a sentient dinosaur as little more than a scaly, four-fingered human; paleoartist Gregory S. Paul called its anthropomorphism “suspicious”, and I’m inclined to agree.  While I’m sure that Dale Russell meant well, this depiction of a sentient theropod is unimaginative at best, and willfully ignorant of theropod evolutionary trends at worst.

Why do I say “willfully” ignorant?  Because there are sentient theropods alive today!

Crows have demonstrated remarkable intelligence, empathy, and ingenuity, leading some to classify them as sentient beings.  You might also notice that crows don’t have a humanoid body plan; they’re capable of making and using tools with just their beaks and feet.  An intelligent dinosaur would likely do the same, retaining a more traditional theropod body plan.

What dinosaurs would have become intelligent, had they survived?  Hard to say; like I said above, brain size and brain-to-body ratio do not necessarily correlate with intelligence.  However, we do know that tyrannosaurs had brains that were more structurally similar to modern birds than most dinosaurs did.  If I had to bet on a potential candidate for dinosaur sentience, I’d pick a small tyrannosaur; a dinosaur with a very advanced brain, but one that needed to use it to outsmart bigger and stronger predators of comparable intelligence, not just its prey.

I think a good candidate is Dryptosaurus, a 25-foot-long tyrannosaurid from Late Cretaceous North America.  Although large by the standards of modern predators, Dryptosaurus was fairly small for a Late Cretaceous tyrannosaur, and probably got muscled away from more than a few kills by bigger predators.  Who knows?  Had the dinosaurs survived, it might not have taken 65 million years for Dryptosaurus to get smarter…

Dinosaur Group D&D Alignments
  • Lawful Good: Marginocephalians (Pachycephalosaurs & Ceratopsians)
  • Neutral Good: Ornithopods
  • Chaotic Good: Non-Avialan Maniraptorans (Therizinosaurs, Alvarezsaurs, Oviraptorosaurs, Dromaeosaurs, Troodontids)
  • Lawful Neutral: Non-Averaptoran Averostrans (Ceratosaurs & Megalosaurs)
  • True Neutral: Non-Maniraptoran Averaptorans (Carnosaurs, Megaraptors, Tyrannosauroids, Compsognathids, Ornithomimosaurs)
  • Chaotic Neutral: Birds
  • Lawful Evil: Sauropods
  • Neutral Evil: Thyreophorans (Stegosaurs & Ankylosaurs)
  • Chaotic Evil: Basal Forms (Heterodontosaurs, Prosauropods, Herrerasaurs, Coelophysoids)

Ouranodromeus artifex

Height: 1m
Weight: 20kg
Classification: Maniraptora, Paraves, Troodontidae, Neotroodontidae, Dexteropterygidae, Sapiornithoides


As promised, here is the droman skeleton!  They look pretty silly without feathers, which is why I’ve included two silhouettes.  To be honest, the whole reason I designed them with prominent head feathers was to hide the awkwardly large braincase, which made many dinosauroids ugly imo.  Also, as a cartoonist the feathers will prove useful for emoting.

Below is a brief list of key anatomical features.

Enlarged braincase - Self-explanatory, really
Reduced jaw muscles - Allowed more space for the brain to grow
Reduced muzzle - Correlated with reduced jaw muscles, as well as the increasingly omnivorous diet, the lack of need for a killing bite, and the increase in neotenous features
Short, thick neck - Supports the enlarged head closer to the center of gravity
Long head feathers - For display and conveying emotion
Long forearms - Used for flight in juveniles and for a lengthy reach in adults
Opposable thumbs - For manipulation
Dexterous feet - Reversed hallux is held off the ground while walking
Opisthopubic pelvis

I promise I’ll have a write-up on how/why dromans are sapient soon!  I’ve put tons of thought into it and every new piece of information I’ve learned over the past few months has reinforced my ideas on how it happened.  As a bit of a teaser, they’re an extremely social species with a huge emphasis on showing off in every way.  Intelligence, creativity and dexterity, while moderately useful for survival, are expensive traits that wouldn’t really need to develop past a certain point…that is, if it hadn’t been for runaway sexual selection!

Here have a chickeny Troodontid! Based on Jingengopteryx, but that has well preserved feathers and it’s tail is not like this really, so perhaps a closely related species. Or a male one? The style was inspired by Itō Jakuchū’s roosters.
Also available on a t-shirt and other stuff here!

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More dinosaur concepts! I’ve decided Sealights is gonna be melanistic, and shadowed by superstition wherever she goes. Poor girl.

Some centrosaurs who are a big part of Sealights life–Shoot is her adopted momma, Glaciertusk is King of the Herd and Shoot’s son, Baldface is an aggressive old hind, and Whistler is Sealights’ closest friend.

And then an unfinished painting of some silly troodontids who thought raiding an hesperonychus nest was a smart idea. I’m not gonna finish it but I thought it was corny.

Meet my new Troodon OC! Their name in Teebs and they’ll be appearing in my Jurassic World AU.  Like all of Jurassic World’s animals, (since they stopped using amphibian DNA, at least), Teebs’s biological sex is female, but since they’re a dinosaur, they don’t give a synapsid’s butt about gender. Call them whatever you like!

(For any of you MTMTE fans out there who may come across the post, yes, they were named after Trailbreaker’s fan?nickname. I dunno whether his nickname is canon or not. I just thought it was cute. Also, Teebs’s human caretaker is a massive transformers nerd.) 

Because the more, the merrier, more dinosaurs should be cropping up soon. 

The concept of Teebs was heavily inspired by @iguanodont‘s Soap and several depictions of Troodontids with facial disks floating around Tumblr. (If you’re the one that came up with that paleomeme, please contact me so I can give you proper credit!)

@theasgardiantimelord this was the character who the Raptor Squad would pick a fight with who I told you about. Big Boy. 

Mongolia of the Cretaceous

Late Cretaceous Mongolia is one of the richest locations for dinosaur fossil hunting, and a great variety of dinosaurs are known, from the familiar Velociraptor and Protoceratops to the utter weirdness of Deinocheirus and Achillobator. This section, bordered by Vista View to the east and the aquarium and Synapsid Alley to the south, showcases animals from four formations - the Bayan Shireh Formation of Cenomanian Burkhant, the Djadochta Formation of Omnogovi, Nemegt Formation of Omnogovi,  and the Iren Dabasu Formation of Inner Mongolia (technically China, but it’s only fifty miles away).

The bigger animals are found to the north. The Therizinosaurus, Alioramus, and Gigantoraptor exhibits are more densely forested. A boardwalk runs on one edge of the Therizinosaurus exhibit, bringing you closer to their eye level, while on the other side you can see their majesty from the ground - if you can see them in the trees. In contrast, the Nemegt Prairie paddock, shared by Gallimimus and Saurolophus, is noticeably more open. In between the two is a communal paddock. We rotate the larger plant-eaters into there so we can safely clean the exhibits, and sometimes to let them meet with each other - they live in different habitats and normally wouldn’t.

In the middle of the exhibit is the “Duck Pond”, a swamp shared by Ol’ Sam and a flock of Teviornis. Don’t worry, they won’t fly away - their wings are clipped and they spent most of their time wading anyways. To the south of the pond are three chickenparrots from Djadochta, and to the east live alvarezsaurs, ceratopsians, dromaeosaurids and troodontids. Each of these is open and scrubby. Of course Velociraptor is among these - everyone flocks to see them. They probably get the most attention out of everything here.

Animals here:

  • Achillobator
  • Alioramus
  • Citipati
  • Deinocheirus
  • Gallimimus
  • Gigantoraptor
  • Khaan
  • Oviraptor
  • Protoceratops
  • Saurolophus
  • Saurornithoides
  • Shuvuuia
  • Teviornis
  • Therizinosaurus
  • Velociraptor
  • Zanabazar

mage-lochlyn  asked:

Ignorant teen here- do you think that there could have been an evolutionary branch, where some raptors began to show more bird like traits while others remained raptors? Like how there are both humans and chimpanzees today, from a common ancestor?

Yep, that’s basically what we think happened!

Here’s the family tree of Eumaniraptora, the group that contains “raptors” and modern-day birds (It might be a little different from this; Deinonychosauria may actually be two distinct groups. But that doesn’t really have much impact on this.).  The earliest eumaniraptorans were animals like Archaeopteryx, the famous “first bird”.

As you can see, it has the raised “sickle claw” on the second toe that has come to be associated with “raptors”. 

Early deinonychosaurs were similar to Microraptor. There are a lot of anatomical differences, including the elongated bone struts in the tail to stiffen it, but it’s very similar to Archaeopteryx.

The earliest “true birds” (Birds is a very loosely defined term. Meg Dickson of @a-dinosaur-a-day gave a rundown of it here) were very similar to Jeholornis. It retains the sickle claw as well.

Then there’s Jinfengopteryx, a troodont (probably). It’s another early deinonychosaur*, but you can see that while it retains the sickle claw, its arms are much shorter.

Later deinonychosaurs continued this. The “sickle claws” enlarged, and they kept fairly short arms.

Later avialans, however, lost their raised sickle claws and instead kept all four toes on the ground.

*Taxonomic rant: We’re not sure where the group that we call “troodontidae” fits in taxonomically. One widely accepted position states that it is a sister taxon to dromaeosauriade, forming the deinonychosauria. However, there’s also evidence suggesting that this group may be closer to modern birds. This causes a little issue on what to call these groups, as troodontidae is defined as (Troodon>Dromaeosaurus)(i.e., all individuals closer to Troodon than to Dromaeosaurus), but Avialae is defined as (Passer>Deinonychus). Thus, if “troodontids” were closer to modern birds than to dromaeosaurs, modern birds would be troodontids and “troodontids” would be avialans. Additionally, Deinonychosauria is defined as (Deinonychus+Troodon)(i.e., the most recent common ancester of those two genera and all of that ancestor’s descendants). This would mean that if “troodonts” were closer to modern birds, modern birds would be deinonychosaurs. Clade definitions are tricky like that. And that’s not even getting into synonymous clade names.

All skeletals by Scott Hartman ( @skeletaldrawing ), taken from his website.