#sauropsid

[vickysaurus]

A long, long time ago, back in the Carboniferous, one species of little amniotes was split in two. As their paths diverged, one group’s descendants became the sauropsids - such as reptiles, birds, and other dinosaurs - and the other group’s descendants became the synapsids - such as therapsids, cynodonts, and mammals. As the millions of years stretched on, our two clades have shared the same planet and lived alongside each other as each evolved into ever new and fascinating forms.

(in every panel, there’s a sauropsid on the left and a synapsid on the right)

-In the Permian, a Titanophoneus looks up in wonder as a Weigeltisaurus glides overhead.

-In the Triassic, a Coelophysis and a Kataigidodon cautiously share a bite of a large piece of carrion they both found.

-In the Jurassic, a Maiopatagium glides around a feeding Mamenchisaurus, hunting the insects attracted by the huge sauropod.

-In the Cretaceous, a Didelphodon captures a young Bambiraptor.

-In the Paleogene, a Picavus rests for a moment on the head of a Paraceratherium.

-In the Neogene, a Titanis hunts a Cormohipparion.

-In the Quaternary, a human gives her pet cockatiel scritches.

#synapsid #sauropsid #reptile #dinosaur #bird #evolution #amniote #titanophoneus #weigeltisaurus #coelophysis #kataigidodon #maiopatagium #mamenchisaurus #didelphodon #bambiraptor #picavus #paraceratherium #titanis #terror bird #cormohipparion #human #cockatiel #i based the coelophysis and didelphodon coloration on walking with dinosaurs #but gave the coelophysis feathers #also as you can see i drew titanis way too fat at first and had inked it before i noticed my mistake #human is based mostly on myself #though i do not have a cockatiel #(yet?) #paleoart #my art

[rxttenfish]

i’m so bothered by how brian doesn’t have human dentition here. like.

this mans doesnt have canine teeth. hell, he doesn’t have any differentiated teeth at all, he’s a homodont. is brian even a mammal? are zombies not mammalian in the lore of monster prom?

he has way too many teeth too and they go too far back. what the fuck.

#all the care guide says is 'biomass' #monster prom #Monster Roadtrip #me shaking brian and asking him if he's a sauropsid or a synapsid

[carnivalcarriondiscarded]

im sorry im rewatching Dominion and its so fucking funny. they really brought dimetrodon & lystrosaurus' Permian Asses into it

#cmonnnnnnnn #i fondly remember struggling not to burst out laughing in the theater bc CMONNNNNN #and then the whole GiGA iS tHe biGgESt LaNd cARniVoRe eVeR #SHUT UPPPPP does spinosaurus mean nothing to you? have you forgotten her? #theyre out here acting like giga is some bad bitch #please they were only a smidge bigger than t.rex #and rexes could still body them not even a question #if. yk. they existed at the same time Which They Did Not #yk i love how the movies are like 't-rex vs [insert dino here] who would win' #and??? rex??? like every time??? she was The bad bitch. there's a reason she's called the King!! #the only loss i accept as fully realistic is prehistoric planet's rex vs quetz scenario #cause yeah. i dont think anyone would willingly fuck with a quetz #but still... if they Had to fight... yeah rex would still win #ANYWAY YEAH DOMINION BRINGING PERMIAN ANIMALS INTO IT #AND NOT EVEN SAUROPSIDS LIKE????? #DIMETRODON AND LYSTROSAURUS ARE SYNAPSIDS. LITERALLY THE START OF THE MAMMAL BRANCH OF EVOLUTION #the rest of the jurassic bullfuckery i can accept but That? too funny. too absurd #fuckin... permian animals.... in a jurassic park movie #i thought we were cooking with mesozoic Dinosaurs here... #absolutely unprompted #at least the movie gave us an on-screen theri some Gorgeous parasaurs a 'Feathered' Quetz... finally some good fucking food #still not as good as prehistoric planet's top tier beautiful amazing showstopping Up To Date dinosaurs #oh theyre so beautiful.... i cant wait for s.3 if we're getting a s.3 #im still waiting for some parasaurolophus action please!! #so that i can have something better than watching Crisp Rat live my dream!!!

[goji-pilled]

also dimetrodon is closer related to you and me than it is to dinosaurs

this is your evolutionary weird aunt put respect on her name

#/thats a big joke btw #since its (as far as im aware) a pelycosaur and not directly related to the line mammals stem from #however much like the therapsids (which we are technically a part of) theyre synapsids so #im seeing this as reason enough for the joke #however the first bit is true #due to being a synapsid and not a sauropsid its cliser related to you and me than dinosaurs

[a-dinosaur-a-day]

one second if we are not reptiles than are we at least Reptiliomorpha?

We are!

#reptiliomorpha #reptiles #synapsids #sauropsids

[sharkestry]

RETVRN

#turtle #turtles #reptiles #sauropsids #/j

[new-dinosaurs]

Gremlin slobodorum Ryan et al., 2023 (new genus and species)

(Type frontal [bone in the top of the skull] of Gremlin slobodorum, from Ryan et al., 2023)

Meaning of name: Gremlin = gremlin [creature in 20th-Century folklore blamed for aircraft malfunctions]; slobodorum = for Ed and Wendy Sloboda [contributors to paleontological discoveries in Alberta, the latter of whom discovered the original fossil]

Age: Late Cretaceous (Campanian), between 76.7–77 million years ago

Where found: Oldman Formation, Alberta, Canada

How much is known: A partial right frontal (bone in the top of the skull).

Notes: Gremlin was a leptoceratopsid ceratopsian. Unlike the better known ceratopsid ceratopsians (such as Triceratops), leptoceratopsids were relatively small (mostly around sheep-sized) and lacked horns. Although it is very incompletely known, Gremlin can be distinguished from other leptoceratopsids by the presence of a ridge running across the top of each frontal ("tr" in the figure above). It also fills a gap in time in the fossil record of leptoceratopsids in Alberta, being intermediate in age between the older Gryphoceratops from the Milk River Formation and the younger Unescoceratops from the Dinosaur Park Formation.

Reference: Ryan, M.J., L. Micucci, H. Rizo, C. Sullivan, Y.-N. Lee, and D.C. Evans. 2023. A new Late Cretaceous leptoceratopsid (Dinosauria: Ceratopsia) from the Oldman Formation (Campanian) of Alberta, Canada. Pp. 151–165, in Y.-N. Lee (ed.), Windows Into Sauropsid and Synapsid Evolution. Dinosaur Science Center Press, Seoul.

#Palaeoblr #Dinosaurs #Gremlin #Late Cretaceous #North America #Ceratopsia #2023 #Extinct

[amnhnyc]

🛡️This #FossilFriday, get to know Scutosaurus karpinskii, or the “shield lizard!” 🦎It lived about 253 million years ago during the Late Permian. Scutosaurus is one of the pareiasaurs, a group of early sauropsids that were probably related to the smaller procolophonids. The pareiasaurs had spikes and thickened knobs around the skull. Their teeth were simple pegs, presumably adapted for eating plants. Pareiasaur fossils have been found in Africa, Europe, and Asia. Spot this one in the Museum’s Hall of Vertebrate Origins! Photo: E. Louis/ © AMNH #amnh #NaturalHistory #fossils #paleontology #Scutosaurus #dyk #museums #nyc #uws (at American Museum of Natural History) https://www.instagram.com/p/Cki6zL6u-3n/?igshid=NGJjMDIxMWI=

#fossilfriday #amnh #naturalhistory #fossils #paleontology #scutosaurus #dyk #museums #nyc #uws

[alphynix]

Cabarzia trostheidei here lived during the early Permian in what is now Germany, about 295 million years ago.

Despite its very lizard-like appearance it was actually part of the varanopid lineage, a group of scaly amniotes traditionally classified as early synapsids (distant relatives of modern mammals), but which more recently have been proposed to instead be sauropsid reptiles closer related to early diapsids.

It was around 50cm long (1'8"), and its short arms, long legs, slender body, and long tail suggest it was capable of shifting into a bipedal posture when running at high speeds, similarly to some modern lizards – probably mainly to escape from larger predators, but possibly also used to pursue fast-moving prey like flying insects.

And whether varanopids were actually synapsids or sauropsids, this makes Cabarzia the earliest known example of an animal running on two legs.

———

Nix Illustration | Tumblr | Twitter | Patreon

#science illustration #paleontology #paleoart #palaeoblr #cabarzia #varanopidae #amniote #tetrapod #art #bipedal #gotta go fast

[katborg82]

Happy Easter everyone! While you may never see a bunny laying colorful eggs, it may come as a surprise that once upon a time, egg-laying mammals were the norm. In fact, it wasn't until as recently as about 140 Mya that mammals started giving live birth. In fact some mammals, like the echidna and platypus, still lay eggs today.

Morganucodon (Glamorgan Tooth), was a very small, early mammaliform that lived from the late Triassic to the middle Jurassic (~205-163 Mya). This primitive mammal's skull was only about 2-3 cm in length, and it had the appearance of a mouse or shrew. It is thought to have been a burrower, and its eggs were probably small and leathery, much like the eggs of modern monotremes.

The amniotic egg was an important milestone in the evolution of life. While amphibians still lay their jelly like spawn in the water, later tetrapods would adapt a more advanced egg with a protective shell. This would allow these animals to live further inland, without needing to rely on the water so much. We think these amniotes diverged during the Carboniferous about 312 Mya, but since eggs typically don't fossilize well, our earliest fossil evidence of eggs don't appear until about 195 Mya, a group of fossilized eggs laid by stem Sauropod dinosaurs in the early Jurassic.

The amniotes would split into two major groups, the Synapsids and Sauropsids. The ancestors of today's mammals and reptiles respectively.

#happy easter #paleoart #paleontology #evolution #mammals #morganucodon #eggs #easter #easter egg #zoology #amniote

[vickysaurus-art]

My Art in 2022

January

Humans and our Cousins. I started off 2022 with the idea of drawing every group of living creatures in order of how closely related to us they are. It starts with humans, makes its way through the primates, mammals, vertebrates, animals, eukaryotes, and finally ends with E. coli as its final image, representing the bacteria. This project was actually a gateway that got me into doing paleoart, as I felt the need to fill in the rather large leap from the platypus to the macaw by drawing some synapsids.

February

Saurornitholestes leaps across a river. I really love this piece, but somehow it never scans in quite right.

March

Moschops in love. Synapsids are wonderful beasts that really do deserve more of a spotlight. I do adore how friend-shaped Moschops is.

April

Mammaliaforms of Jurassic China. Mesozoic mammals were way more interesting and diverse than we often think they were, and Jurassic China in particular had a whole lot of very diverse Docodonts that I wanted to depict. The fact that they just so happened to share their habitat with Yi qi was icing on the cake.

May

The last Edmontosaurus. With the beauty of spring all around me, I was inspired to create this jolly piece by Riley Black's The Last Days of the Dinosaurs. It depicts a hatchling Edmontosaurus whose egg was kept safe from the global firestorm the meteorite impact caused.

June

Troodon playing in a pile of leaves. The seasonally appropriate art continues. This one was inspired by @a-dinosaur-a-day during a Prehistoric Planet watch party as we talked about how angiosperms had already done their big take-over during the Cretaceous and ey mentioned the idea of a Troodon playing in autumn leaves and how cute it'd be.

July

Synapsids and sauropsids through the ages. This one starts with the common ancestors of the synapsids and sauropsids being split from one another in the Carboniferous, and then each next panel shows a synapsid and a sauropsid interacting in the next period. The sauropsid is always on the left and the synapsid on the right.

August

Raptor Red. I read Robert Bakker's Raptor Red in August, and ended up doing three fanarts of it. Two of these were technically finished in September, but I'm counting them for August anyway.

September

Assorted bird-inspired Deinonychosaurians. I used a bunch of bird photos to draw Dromaeosaurs and Troodontids from.

October

Stargazing Zhenyuanlong. My Beasts of the Mesozoic Zhenyuanlong has a little bit of difficulty standing up, but gets into this pensive sitting pose very easily. It provided quite a nice model for this piece.

November

Feeding my pet Velociraptor. I moved in November, so my spare time was very limited, but I did find time for this little drawing. Please be a more responsible pet owner than I am and put some sort of claw gloves on your pet dromaeosaurs.

December

Mazothairos chase a passing Meganeura. I am working on a geologic timeline running along the walls of my new appartment, and want to add some palaeoart to go with it. However, basically all of my own paleoart is either set in the Mesozoic or the Permian, with nothing in the other periods! So here's a piece to extend my temporal range a bit into the Carboniferous.

#paleoart #palaeoblr #paleoblr #my art #2022 #okay i'm definitely not tagging everything in these pieces #uh let's see about content warnings #cw: bugs #cw: animal death

[quark-nova]

It always bugs me how "synapsid" and "sauropsid" sound like they'd be etymologically related but they're absolutely not

(for context, "synapsid" means "with arch" and "sauropsid" means "lizard face" - you'd believe the "-psid" ending in those two sister clades have anything to do with each other, they don't)

#palaeoblr #i guess

[makairodonx]

A Dentaneosuchus crassiproratus, the newly described Sebecid crocodylomorph hailing from the Middle Eocene Sables du Castrais Formation of Southern France 41-37 million years ago, strolls along a riverbank with the head of a Lophiodon crushed in its jaws. D.crassiprotatus had a large skull with powerful jaws that was nearly a meter in length, and the animal itself could also reach a length of up to 5 meters long, making it one of the largest sebecids alongside the South American Barinasuchus as well as possibly Europe’s largest terrestrial predator during the Eocene. So even after the extinction of the dinosaurs, it seems that European mammals would still have to somehow live under the shadow of large sauropsids such as Dentaneosuchus and other crocodylomorphs as well as giant birds such as the herbivorous bird Gastonis.

#paleoart #paleontology #paleoillustration #dentaneosuchus #sebecid #crocodylomorpha #eocene #cenozoic life #cenozoology #cenozoic #europe #france

[synblr]

A Prologue to Amniotes

Part IV - The egg came first

Late Mississippian. It has been 40 million years since tetrapods first walked on land. Every generation since then, they have remained bound to the waters for at least one moment in their life cycle.

Despite their adaptations for walking on land, early tetrapod reproduction wasn't much different from that of their fish predecessors. Spawning, or external fertilization of an egg mass, with eggs covered in a gelatinous membrane laid in a body of water, prevending the permeable eggs from dessicating.

But things are now changing. While the mid-Carboniferous rainforests still provide safe, moist environments, reptiliomorphs have already begun adventuring further inland. As swamps left room to humid crevices to lay eggs in, creatures like Casineria also began to develop internal fertilization, refusing to leave their reproduction at the mercy of the elements.

Casineria kiddi, an early amniote relative by ДиБгд (CC-BY-SA 4.0)

Adventuring into even drier environments, ancestors of amniotes still had to solve two crucial problems. While a harder shell could prevent the egg from dessicating, it would doom the embryo to suffocation, by preventing it to get rid of carbon dioxide. Furthermore, the small size of the eggs - also constrained by gas exchange - limited the full development of the embryo before hatching.

To solve both of these issues, the outer layers of the eggs would have to be reshaped. The outer gelatinous layer was replaced by a fibrous membrane for protection, and later by the three layers known as extraembryonic membranes: the amnion, chorion and allantois. The innermost amnion would surround and protect the embryo, while the outer chorion and sac-like allantois take care of gas exchange and waste removal.

In the safety of the amniotic egg, the embryo was able to hatch considerably more developed than before. Skipping the larval stage, amniote youngs would hatch as miniatures of the adults, making them able to face the challenges of the Carboniferous world from the day of their birth.

Structure of the amniotic egg, by Lumen Learning (CC-BY)

As the Pennsylvanian began and climate started to dry out, later developments would perfect the ability of early amniotes to survive in drier, fully terrestrial environments. A thicker, less permeable skin will develop, incorporating keratin and preventing dessication. Cutaneous respiration, requiring the skin to be moist at all times, will give way to costal respiration, harnessing the power of the ribcage to expand and contract the lungs. Cutting their last ties with the water, amniotes had finally conquered the land.

On one fateful day, not long after the amniote body plan was perfected, one of the most decisive splits in vertebrate history would occur. A divergence of the amniotes into two major lineages, alternating domination of land, sea and sky for the next 320 million years. But sauropsids like Hylonomus would at first stay in the shadows. The stage of the Late Pennsylvanian would be left to their rivals and cousins, as forerunners like Archaeothyris paved the way for their own lineage: the synapsids.

Archaeothyris, one of the first known synapsids, by ArthurWeasley (CC BY-SA 3.0)

#palaeoblr #a prologue to amniotes #carboniferous #mississippian #pennsylvanian #amniota

[a-dinosaur-a-day]

Hypothetical scenario: you’ve been granted the budget of your average big summer blockbuster movie, but you can only use it to fund a movie / TV series on dinosaurs or prehistoric animals. What would that ideal piece of paleo-programming look like?

o-o

I'd tell the entire story of dinosaurs, from beginning to today. Start with the end-Permian extinction and how that lead to the empty niches that allowed sauropsids to diversify. Discuss the evolution of Archosaurs and what made early Dinosaurs unique from other animals (and highlight that those things were usually things that make birds unique from other animals today). I'd then go into their diversification in each period, showcasing how different environmental events affected their evolution. I wouldn't stop at the KPg, of course; I would talk about why the dinosaurs that survived (birds) did, while others didn't. I then would dig into the Cenozoic and how dinosaurs have diversified through that, discussing notable major groups and their responses to environmental change. I would finish with the modern day, the sheer diversity of living dinosaur species, and how these dinosaurs are affected by anthropogenic climate change.

can you tell I think about this a lot and wish some magical rich person would descend from the clouds to give the money I need to make my projects happen?

#dinosaurs #dinosaur documentaries #birds #documentaries #dinodocs #palaeoblr #birblr

[parakaryote]

Two artificially-created shapeshifters: the cockatrice (chicken that is a partial weresnake — the one in the picture is specifically a grey ratsnake) and the ratbit (rat that is a wererabbit). They generally only transform when stressed.

I’m keeping the details secret for now, but therianthropy in this setting is the result of what can roughly be described as an “infection”. These creatures are the result of a research organization messing around with the “pathogen” that causes it, changing the animals whose characteristics it confers and infecting different species with it.

The ordinary version of the “pathogen” only confers traits of wolves, big cats, or bears. Even with modifications, there are limits; mammals can only gain traits of other mammals, and sauropsids (birds and reptiles) can only gain traits of other sauropsids.

Cockatrices also have a forked tongue in secondary form, and a functional Jacobson’s Organ in both forms.

Pasted alt text under the cut:

First picture: A simple diagram of a cockatrice. On the left is a white chicken with no earlobes and grey-and-off-white scales covering most of its head, labelled “Primary form”. On the right is the same chicken with small tooth-like protrusions on the sides of its beak and a long scaly tail, labelled “Secondary form”. End ID.

Second picture: A simple diagram of a “ratbit”, a rat that can turn into a rabbit-like creature. On the left is an ordinary-looking grey rat, labelled “Primary form”. On the right is its rabbit (secondary) form, which retains the eyes, nose, and hairless spots (paws, nose, tail) of the primary form. Text clarifies that the creature also has rabbit teeth in both forms. End ID.

#The Claws of the Ounce #original art #original story #worldbuilding #fantasy biology #speculative biology #cockatrice #shapeshifter