What was 11 meters (36ft) long, had a sail on its back, and had arms bigger than an adult human?

Deinocheirus mirificus!

Yep, the big paleo news this weekend was the official announcement of some new fossil material for this particular dinosaur.

Deinocheirus (“terrible hand”) came from the Late Cretaceous of the Gobi desert, about 70 million years ago. Originally discovered in 1965, the only bones known were a set of enormous arms and a few scattered ribs and vertebrae. It was a long-standing mystery for paleontologists. Was it a megalosaur? A carnosaur? Some new type of theropod altogether? A predator or a herbivore?

Some more recent studies suggested it might be an ornithomimosaur, albeit a fairly primitive one based on the arm anatomy. With the two new specimens that have been found, we’ve now got confirmation of that placement — Deinocheirus really was an enormous “ostrich mimic”, the largest known for that group.

And it had a sail-back.

I don’t think anybody was expecting that.

This is the famous Velociraptor mongoliensis in its native late Cretaceous Gobi Desert. Velociraptor was a small dromaeosaur, or raptor dinosaur, and contrary to its most famous depictions was almost certainly feathered from head to tail. This is no longer based merely on phylogenic evidence, either - as of 2007, reanalysis of the fossil has shown that its posterior forearm contains quite obvious quill knobs.

Velociraptor surely went after larger prey like Protoceratops at least occasionally, as we have fossil evidence that it certainly did so. However, like many modern mid-sized carnivores, its diet probably consisted of a large proportion of much smaller animals, which it may have ambushed or sniffed out of crevices. I imagine such a predation event would have been rather felid in nature, wherein the animal displayed a curious mixture of predatory grace and pure silly ridiculousness as it bounced and flailed after a frantic prey animal. In this case the prey in question is Zalambdalestes, a small shrewlike eutherian from the Djadochta Formation of Inner Mongolia.

How Birds Evolved From Small Meat-Eating Dinosaurs

by Joel N. Shurkin, ISNS Contributor

Some time, perhaps 150 million years ago, small-feathered dinosaurs called maniraptorans began to develop longer arms and shorter hind legs, kick- starting the evolutionary process to becoming the birds we see today.

All of today’s 10,000 bird species, from the hummingbird to the condor, evolved from that simultaneous physiological change, posits a paper published in the journal Evolution by Hans Larsson, a macroevolution researcher at McGill in University’s Redpath Museum in Montreal, and Alexander Dececchin, a graduate student now at the University of South Dakota in Vermillion. Their research was based on dozens of data sets from fossil records.

Before the transformation began, the relationship between the size of the maniraptorans’ limbs and body had been steady through millions of years, they said. Not only that, the species were surviving just fine on the ground, not in trees, as earlier theories about maniraptorans suggested…

(read more: Live Science)

photo by H. Raab

K is for Khaan

Khaan mckennai was an oviraptorid from the Late Cretaceous of Mongolia, about 75 million years ago. About 1.2m (4ft) long, it was initially identified as belonging to the genus “Ingenia" before being assigned its own unique name in 2001.

Oviraptorids were members of the maniraptorans, closely related to birds and “raptors”. They were initially considered to be specialized egg-eaters due to an Oviraptor fossil discovered on top of a nest which was thought to belong to the ceratopsian Protoceratops. (Hence the name “Oviraptor”, meaning “egg thief”.) Later specimens found during the 1990s showed oviraptorids clearly brooding on top of nests, however, and the original eggs turned out to have belonged to the Oviraptor the whole time.

Here is my rendition of Eosinopteryx brevipenna, the new troodontid described last week in Nature Communications. This tiny feathery, from the Late Jurassic Tiaojishan formation of Liaoning, China, differs from other basal troodontids in that it lacked the long feathers on the metatarsals and pes that typifies related animals, such as Anchiornis. It also had much shorter footclaws than related species, and this together with the lack of “legwings” indicates it was very likely a terrestrial bird. The animal is also a bit unusual in that its tail is rather short and lacks any sign of retrices, which gives it a bit unusual and somehow more “primitive” appearance than its relatives.

Here, the little fellow perches atop a mossy stump, possibly the highest vantage point it was able to manage. The paper makes no mention of whether the ungual on the second digit of the foot could be retracted, but the fossil’s second pedal claw is clearly larger than the other claws on the foot, so it’s possible it was used to aid in balance as well as predation.

Photoshop CS4.


3-day dino drawing challenge

day 5: favourite maniraptoran- Archaeopteryx

….still kind of doing these and yes, I skipped day 4 because that comes under a different day. Anyway! This is supposed to be archaeopteryx doing that wing stretchy pose birds do… I say supposed to be, since as always I’m not claiming scientific accuracy here. (also aware that at least some of their feathers were supposed to be black but… it ended up being… not black <.<)


This one looks kind of strange because I was experimenting with a different graphics program and colouring technique. It sort of didn’t work, sadly. So here’s the mostly flat coloured version instead.

Here’s my submission to Love in the Time of Chasmosaurs' version of the “All Yesterdays” contest. This version of the contest is differentiated from the original by requiring the artist to illustrate the speculative behavior in a style different from their usual, with a specific emphasis on straying from the hyper-detailed, realistic style that most paleoartists seem to be trying to capture these days. I tried a sort of cell-shaded, pseudo-vector type of look for mine, which I'm sure most of you will notice is very different from my usual fare.

Anyway, this is a little different from most entries to this contest in that while it’s speculative, it is something that I genuinely believe is the case (that Microraptor was an omnivore), and I think it’s perfectly possible that one of the ~300 undescribed specimens of this animal may preserve plant matter gut contents. Hard to say. In any case, I think that Microraptor has certain features that are consistent with omnivory in maniraptorans, including having somewhat unusual dentition by dromaeosaur standards.

Here I’ve depicted it munching on a tasty cycad fruit.

I intend to do a more in-depth blog post exploring this concept sometime in the coming weeks. I also hope that my watchers aren’t sick of me drawing Microraptors yet… there will be more to come.

2

Tachiraptor admirabilis is a basal near-averostran sauropod from the La Quinta formation of Venezuela. La Quinta, sounds familiar, right? Yep, Laquintasaura is not safe. You can also see the poor little ornithopods in the image above.

The remains, which consist of a tibia and partial pelvis, were briefly described in the Laquintasaura paper. This is the full description.

Tachiraptor has a number of interesting implications for the evolution of theropods. Averostra - consisting of the majority of post-Triassic theropods - have very obscure origins, with very few definite specimens from the Upper Jurassic.Tachiraptor is a major factor in clearing up the course of the evolution of theropods - the existence of Tachiraptor within the dilophosaurid-like group of theropods implies that averostrans did indeed have its origins during this time and at this place. It also provides some insight into how a ‘ghost lineage’, or implied evolutionary path, of averostran theropods, might have survived over the course of the Jurassic to develop into the famous allosaurs, tyrannosaurs, and maniraptorans that we all love.

The PalaeoFellows, as usual, have come up with a design, albeit slightly late. Since not much of Tachiraptor is known, here it’s a hybrid of Cryolophosaurus and Sinosaurus (formerly Dilophosaurus sinensis) with a speculative crest. Crestless Tachiraptor chasing Laquintasaura up to by Maurilio Oliveira, if I’m right.

Full paper here.

Child of Ayatlan

So, the Ixal used to have wings. And I am a huge nerd about birds, theropods, bird evolution, and pretty much everything that would lead to trying to imagine what these vaguely humanoid maniraptoran bird people would look like with wings. In order to stay true-ish to how they appear in game, I had to take some liberties with things like wing anatomy. My deepest apologies to actual scientific illustrators. Further apologies to everyone for using the Ehcatl Nine color scheme instead of the classic enemy Ixal color scheme. I know. This one hurts to look at.

X is for Xixiasaurus

Xixiasaurus henanensis (pronounced “shee-shah-saurus”) was a troodontid from the Late Cretaceous of China, about 83 million years ago. Its size is difficult to estimate, based only on the front portion of a skull, but it may have been somewhere in the region of 1.5m long (5ft).

Troodontids were very bird-like dinosaurs, closely related to both the dromaeosaurs and true birds. They had long legs and appear to have been fast runners, and possessed “sickle claws” on their feet — although not as large or curved as those in their dromaeosaur relatives. Large eyes and asymmetrical ears suggest that they may have been specialized for nocturnal hunting in a manner similar to modern owls, using a keen sense of directional hearing to locate small prey.

They also had some of the biggest brains in relation to body size of all dinosaurs, roughly comparable to those of modern flightless birds. This has led to speculation about their intelligence, and the creation of the (rather problematic) “dinosauroid" thought experiment in the 1980s.

robinabobin tagged me in a thing so here goes i guess

1. Your nickname.
I dont think i have one really?? big gay egg or beck calls me lalex sometimes

2. Your eye colour.
default brown because im boring lmao

3. Your hair colour.
see answer above ffff

4. One fact about you.
i get sexually aroused by all rage comic meme faces

5. Favourite colour.
burgundy B)

7. Favourite celebrity.
I dont really have one?? idk most of the mcu people seem p cool

8. Favourite animal.
anything Maniraptoran omg

9. Favourite song.
Civillian - Wye Oak

10. Favourite book.
tbh i dont rly read much but i like good omens a lot

Im not gunna tag anyone bc im gay do it if u want blebpt

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