Look at all the Archaeopteryx-themed things available through my Kickstarter! It’s not just plushies, I’ve got t-shirts, embroidered patches and pin badges, too! https://www.kickstarter.com/projects/palaeoplushies/palaeoplushies-presents-a-life-size-archaeopteryx
As we all know, there are two major groups of Dinosaurs: Ornithischians and Saurischians; with Ornithischians composed of things like Stegosaurus and Triceratops; and Saurischians consisting of things like Apatosaurus and of course, the theropods, such as Tyrannosaurus and modern birds.
This hypothesis has been accepted for centuries and hasn’t really been challenged in the literature.
Until today.
In a paper that came out in Nature by Baron et al., a thorough taxonomic sampling of dinosaurs was used to examine the earliest divergence of the group - again, traditionally thought to be the split between Ornithischians and Saurischians
They found this instead
I know that cladograms can be confusing for some of you so I made a diagram:
Basically, they found that Ornithischians are actually more closely related to Theropods than either are to Sauropodomorphs.
Proposing the new name Ornithoscelida for this clade; and redefining Dinosauria.
Because the definition of Dinosaurs is the most recent common ancestor Passer domesticus + Triceratops horridus (or Megalosaurus and Iguanodon, it means the same thing) and all of that ancestor’s descendants; that would thus exclude Sauropodomorphs (and imagine the headache SAND [Sauropodomorphs Are Not Dinosaurs] would cause my dudes). So Dinosaurs were redefined as Passer domesticus + Triceratops horridus + Diplodocus carnegii for everyone’s sanity.
But is this study robust?
Well, it’s more robust than a lot of things (Ornithischians tend to be poorly sampled), but it comes to a lot of interesting conclusions, and it’s definitely not the last word on the subject.
They did find some shared characters for their proposed Ornithoscelida that are not found in the new Saurischia, especially in the head; and the similarities between Herrerasaurids and Theropods are thought to be convergent.
They also found Nyasasaurus, what is now thought to be a very derived almost-dinosaur or perhaps even the first true Dinosaur, to be a Sauropodomorph; which - if Nyasasaurus is as old as thought, aka, from the Middle Triassic (currently that’s being re-examined) - would push back dinosaur origins considerably.
In addition, two of the three authors of this paper are responsible for the notorious “Dinosaurs aren’t ancestrally feathered” hypothesis - which my friend John has refuted in this link - and they use this new phylogeny to propose that filamentous integument [the fancy word for feathers] might be just ancestral to Ornithoscelida, and not found in Sauropodomorphs at all. While I will say that that hypothesis has more weight if this is the actual explanation of dinosaur origins; I feel it important to say that the criticisms John, I, and many others had with their ancestral feather paper, still stand (ie, that they don’t consider Pterosaur Pycnofibres to be homologous).
This isn’t the last word on the subject. They don’t include the new taxa, Ixalerpeton and Buriolestes in their analysis, and as we know, Buriolestes does cause some changes to the traditional Saurischian phylogeny. They also don’t include many other taxa that I feel would be relevant for such a study, such as Daemonosaurus, Kulindadromeus, and honestly, a more robust sampling from Ornithischia as a whole.
The analysis is very thorough - and you can trust me to say that, because I’m not entirely the biggest fan of Barret, due to the whole feathered dinosaur argument - but obviously it requires more research, more examining, and replication from other scientists. It does make one thing clear though: the origin of dinosaurs is not set in stone, and we have a lot of work to do to understand it better.
Microraptor, everyone’s favorite 4-winged dinosaur~
I finished the thinggg nice
A quick little Aurornis loosely based on a picture of an owl I saw.
This is Cruralispennia, a very interesting dinosaur despite its tongue-twisting name. It’s a surprisingly fast-growing enantiornithine with strange feathers. Click the image to read my article on it!
Sinosauropteryx going after a Changchengornis
a decent ending
i feel like i’m missing some important context here
Rex but instead of going extinct 66 million years ago it survived long enough to crush a modern gray fox underfoot
Bathornis grallator, a flightless bird about 75cm tall (2′6″) from the Late Eocene and Early Oligocene of Midwestern USA (~37-34 mya).
It was originally mistaken for a long-legged vulture (under the name Neocathartes) when first discovered in the 1940s, but later studies have shown it was actually one of the smaller members of the bathornithids – close cousins of the more well-known South American “terror birds”, successfully occupying terrestrial predator niches alongside large carnivorous mammals.
A guide to color in fossil dinosaurs, now updated with a new enantiornithine specimen and new data on Psittacosaurus.
Epidexipteryx hui
Anchiornis huxleyi ~
By Jack Wood on @thewoodparable
Name: Tongtianlong limosus
Name Meaning: Tongtianyan Dragon
First Described: 2016
Described By: Lü et al.
Classification: Dinosauria, Saurischia, Eusaurischia, Theropoda, Neotheropoda, Averostra, Tetanurae, Orionides, Avetheropoda, Coelurosauria, Tyrannoraptora, Maniraptoriformes, Maniraptora, Pennaraptora, Oviraptorosauria, Caenagnathoidea, Oviraptoridae
Tongtianlong is an Oviraptorid (so a Chickenparrot) from the Nanxiong Formation in Jiangxi Province, China, dating back to the Maastrichtian age of the Late Cretaceous, approximately some time between 72 and 66 million years ago. Unlike other Chickenparrots, it had a dome shaped crest and a very rounded beak, giving its head a very pug-like appearance compared to other Chickenparrots. It was very well preserved, but portions were damaged during the excavation; it was also preserved in a unique pose, its head raised and arms splayed. It may have been trapped in mud, and died during its attempt to break free. It lived alongside a great number of Chickenparrots, such as Banji, Ganzhoussaurus, Jiangxisaurus, Nankangia, and Huanansaurus, as well as other dinosaurs such as Microhadrosaurus, Gannansaurus, Qianzhousaurus, and Nanshiungosaurus.
Sources:
Lü, J., R. Chen, S. L. Brusatte, Y. Zhu, C. Shen. 2016. A Late Cretaceous diversification of Asian oviraptorid dinosaurs: evidence from a new species preserved in an unusual posture. Scientific Reports 6: 35780.
Shout out goes to @tuakpidiwalk!
i gave this character a name but i forgot it and i keep just calling him softboy… hes a troodon! i tried to make body and feathering all sciencey and stuff but his markings are just for fun, they are the same as the anthro version of his character
if u have any tips for paleoart please let me know! i wanna actually get into it as a serious hobby cause i love speculative biology and dinosaurs and all that shit
if you want art like this, check out my commissions! gift art for others is 10% off for the holidays!
To all of you who are celebrating today and tomorrow, I’d like to wish you very Happy Holidays! May you all eat very much <3
A Compsognathus patrolling their mountain territory in winter.
Troodon teeth are very abundant in Alaska, but they are about twice as big as what’s expected for the species in more southern areas. It also seemed to be a more significant member of the ecosystem, as opposed to being much rarer elsewhere. What was happening with the Troodons in Alaska?
Read more at Earth Archives.
You can buy prints and merchandise of this and other illustrations at 252mya.com, go check it out!
