#coelurosaurs

[scienceskink]

I will find you in every life (threat)

I am forever fascinated by the arms race between coelurosaurs and ceratopsians. Among the most famous rivals in palaeomedia growing up was Velociraptor and Protoceratops, Tyrannosaurus and Triceratops, and of course I had to add two of my faves, Gorgosaurus and Styracosaurus!

Long time followers may recognise the bottom two skulls as art I have made previously, fun fact I have been sitting on this idea for a little over two years!

[derived-centrosaur]

Spec-Dinovember Day 17: Rexy and Blue, tyrannosaurs and maniraptorans swap niches

The earliest stages of the Cretaceous were a time of transition. The conifer and cycad plant communities of the past were being replaced by newly evolved angiosperms. With the change in plants came a change in herbivores and with that too a change in carnivores. Across Laurasia sauropods were disappearing, stegosaurs were supplanted by ankylosaurs, and the old guard of ceratosaurs, carnosaurs, and megalosaurs were being replaced by new clades of coelurosaurs. Much as in the Early and Middle Jurassic, this reshuffling of niches allowed for brief but interesting role reversals. During the Hauterivian stage in central Siberia the small carnivore guild is populated by coelurosaurs and a few odd ceratosaurs. Among this first group are members of the Proceratosauridae, tiny Tyrannosaurs, who primarily prey upon the many local mammals and the occasional early ceratopsian. The apex predator niche is occupied by a gigantic Eudromaeosaur. At just over a ton in mass, it is large enough to prey upon even the relict stegosaurs of the area.

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Utahraptor is really odd in that not only is it the largest dromaeosaur, but its also one of the earliest to show up in the fossil record. It's found in the Yellow Cat member of the Cedar Mountain Formation, with essentially only an unconformity and/or the Buckhorn conglomerate separating it from the Jurassic Morrison Formation. Larger carnosaurs don't appear until further up the strat-column in the Ruby Ranch and Mussentuchit Members. This pattern looks like a local extinction of the Jurassic dinosaurs, and then the dromaeosaurs capitalize and quickly fill the large carnivore niche before being outcompeted by a bigger predator that survived somewhere else. So my starting point for this prompt was to take this pattern and put it somewhere that has Early Cretaceous proceratosaurid tyrannosaurs. Most of that clade is Jurassic aged, though Dilong and Yutyrannus are from the Barremian stage. I went with a Siberian location because Kileskus is Siberian (though from the wrong time frame) and there's fragmentary evidence of possible stegosaurs persisting in paleoarctic latitudes there in the middle Cretaceous. So I split the time difference and put all the taxa there. Plus there was probably a period of glaciation during the Hauterivian stage, so this would've been a chilly place and that's neat.

[fishsfailureson]

A Proapteryx demonstrating a hunting tactic unique to apterygiformes. Kiwi have been observed shooting powerful lasers from their eyes, directing it at the forest floor in order to kill any invertebrates before eating them. They can also use these beams in self defense. It is unknown whether or not earlier relatives like Proapteryx had this ability. I am definitely not lying about any of this (<- lying).

[jarvistheallosaurus]

Morrison Formation Theropods, Procreate Wanted to go for that more “sketched” look this time (and cause I’m too lazy to make more refined stuff lol) Disclaimer: not all the species depicted necessarily lived at the same time, they are just from the same formation! Ex: Allosaurus fragilis and Allosaurus jimmadseni lived million years apart and never came into contact with one another. The Morrison formation is a geological layer of rock that dates back the Jurassic Period around 157-145 million years ago. The formation is famous for having an incredibly diverse ecosystem with over 12 to 24 different species of sauropods, most of which were some of the largest animals to ever walk the earth. Additionally, the formation is uniquely home to one of the most diverse group of large predatory theropods including Torvosaurus, Allosaurus, Ceratosaurus, and Marshosaurus. This amount of large predators is extremely rare only really be rivaled in diversity by the Kem Kem formation. Here I showcase just a small sector of the Morrison Formation’s preserved species, the theropods of the Morrison from the smallest to the largest!

[thedrawinggizzard]

Nanotyrannus OC Duo

Their name's are Bloody Mary (left) and Jane (right), both being named after fossils of the two Nanotyrannus species (Mary is a N. Lancensis and Jane is a N. Lethaeus). Mary is an annoying little shit who thinks she is way more of a big deal than she is, and Jane is just tired of everyone thinking she's underage.

Honestly, I still find it funny that nano was the punching bag of the paleo-community for so many years, and then two of them come along at once!

[makairodonx]

Portrait of Guanlong wucaii, an Asian proceratosaurid and an ancient, distant relative of the infamous Tyrannosaurus that lived about 160 million years ago in the Late Jurassic of what is now the Shishugou Formation of Western China.

[originalleftist]

Below is a picture of my all-time favourite fossil. I've probably posted this before, but I'll post it again anyway because its both astoundingly beautiful, and honestly unbelievably that something like this exists:

If you don't know, these images, from various news outlets, are of a piece of amber from Myanmar containing, along with what looks like some insects and plant debris, part of the tail of a tiny young dinosaur, complete with feathers and colour preserved. Not impressions of feathers, which is rare enough, but the actual thing, intact.

I know that there is some controversy about amber from Myanmar in scientific research, because of the human rights issues there. But I still wonder at this thing. This is a creature that lived about 99 million years ago, and there is a piece of it, not an impression left in stone but the actual creature, looking almost as though its still alive, and you could hold it in your hand.

It was the size of a sparrow and "chestnut brown and white", and I love it.

Scientists discover dinosaur trapped in amber in unprecedented find | CNN

The tail of a 99-million-year-old dinosaur has been found entombed in amber, an unprecedented discovery that has blown away scientists.

[a-dinosaur-a-day]

I think I'd place "bird" at coelurosaurs. I'm fine with calling Compsognathus and Guanlong birds, even if it means T.rex is included here.

That's fair, there just isn't a major bird trait gained at that point anymore