Monday, May 4, 2009

The Synapsid Gallery

Welcome to...
Though we often picture modern reptiles as being primitive among vertebrates, this couldn't be further from the truth. The majority of reptiles we see living around us today are the highly diverged and specialized products of millions of years of evolution of the reptilian form. If one traces the reptile family tree back to its roots, you'd hardly recognize most of the earliest forms to claim membership in this group.
Among some of the strangest of these early reptiles were the Synapsids. Not only were they bizarre creatures compared to modern animals, but even more bizarre they are closest related to today's mammals rather than other reptiles.
At the same time, this is not to say that most of them are our direct ancestors. They are rather a major offshoot off the reptilian tree that branched out into an amazing array of diversity as the most successful land animals of their era, only to be devastated and cut down by major extinctions to a few lone twigs. One of these surviving twigs would eventually manage to sprout into a new branch of diversity, our own lineage the modern mammals.
The true heyday of the Synapsids was the Permian, in which they dominated nearly every terrestrial ecosystem and niche in the manner we are used to with dinosaurs or mammals. During this time they evolved into all shapes and sizes, ate plants and meat (or a combination of both), and conquered many environments for the first time by vertebrates.
Despite being less known then Dinosaurs, they were in every way as amazing (though very different and unique in their own ways!). They too evolved all manner of odd ornamentation ranging from sail backs, to elaborate horns and crests, small heads, and even the first ever sabre teeth. Though they would not match the colossal size of the Dinosaurs, these primitive "stem-mammals" would achieve sizes that match those of many of today's largest land animals, and were the first to ever reach such sizes.
If not for the combination of a number of devastating geologic processes and events at the end of the Permian period 250 million years ago they may very well have flourished and prospered longer. However they would nearly be completely extinguished by the worst mass extinction of earth's history.

Despite this tragic end they are far from forgotten today. So come back with us, back 250 million or more years to once again witness our strange relatives...

Lobalopex mordax by Zach Miller

Caesids by Zach Miller

Moschops by James Robins

This is drawn from this angle to get a feeling for its peculiar sprawling stance and huge body. The only extant comparison of a creature approaching this size, but nothing like the bulk, would be the Komodo Dragon, which after all spends a lot of time resting its body on the ground.

Dicynodont QMF15.990 by James Robins

A reconstruction of the as yet un-named Dicynodont QMF15.990, from Cretaceous deposits in Queensland, Australia....yes Cretaceous.....!!!

Bathygnathus borealis by Steven Francis-Coombs
Here's what remains of Bathygnathus borealis, with an outline of its skull (speculative). The one and only specimen represents a sphenacodontid synapsid. It was originally described as the lower jaw, but it turned out later that it was part of the upper jaw. It was discovered on Prince Edward Island.

Sunset on the Karoo by Craig Dylke

A pack of Gorgonopsids settle in for the night, as twilight creeps over Permian South Africa 249 mya.

This picture was composed completely from 3D CG in the program Carrara. This scene gains much from being viewed in a larger version.
There will be "a making of" post about this piece appearing on ART Evolved soon.

Cotylorhynchus Romeri by Rachael Revelle

Whilst Cotylorhynchus could grow to 6 metres in length and weighed up to 2 tons it had a disproportionately small head.

Lycaenops ornatus by Sean Craven

The Xeno-Permian by Zach Miller
A look at a world where Synapsids didn't go extinct 250 million years ago...

Proto-Mammal Fallacy by Glendon Mellow

The Hunt By Nima Sassani
A pack of Inostrancevia take down a Scutosaurus.

Estemmenosuchus by Peter Bond

Gorgonopsid by Peter Bond

Dimetrodon milleri by Peter Bond

Dimetrodon milleri by Peter Bond

 Vananops brevirostris by David Tana

Varanops brevirostris, one of the last surviving pelycosaurs from the early Late Permian. 
Pen on paper, scanned, colored in Adobe Photoshop

Submissions for the Synapsid gallery will still be taken, but due to formatting issues caused by blogger, will be posted in buddles of five. So be sure to get yours in sooner then later to guranteed a spot in the first updates.

Our next gallery will be the flying reptiles, the Pterosaurs. Try to have your entry in by July 1st! Also be sure to "soar" by to check out the entries for this gallery...


Mike Keesey said...

The term "synapsid" is increasingly used cladistically, including mammals -- thus, synapsids are not extinct at all. (I'm a synapsid!) "Stem-mammal" is a handy term for non-mammalian synapsids.

Also, stem-mammals are generally no longer placed in Reptilia. Never really made much sense, since, as the post mentions, they're closer to mammals than to modern reptiles.

Weapon of Mass Imagination said...

Mike- Thanks for the clarification.

I wrote that intro knowing that it wasn't the most technically correct thing I've ever written.

We went with the term Synapsid for the gallery and these critters as all the other previous terms such as "Proto mammal" or "mammal-like reptile" have fallen out of use and are now for some reason taboo (for no good reason I've ever seen other then pretension).

I wouldn't be surprised if "stem mammal" shortly falls out of favour (I hardly see a difference between proto and stem myself as is... I prefer "proto" myself).

I should have mentioned the temporal fenestra thing, but I wrote it late last night :P

I'm seperated from my own Palaeo books down here in New Zealand (I had to leave them all in Canada), and apart from the Permian extinction I don't know a lot about the time period.

I took the reptilan route due to the one kids' book I found in the local library.

A lot of the general public are introduced to Permian "stem mammals" as reptiles in most popular books, and I thought I would use this language and approach to maybe educate a few people that this isn't quite the case. Afterall anyone with a more technical knowledge wouldn't get anything useful out of me anyways (as we have just seen ;p )

My applogies though to the more technically inclined palaeo crowd out there. This was my reasoning for the intro

Glendon Mellow said...

Mike, your own artwork is amazing. Can we expect a submission in the future here? The energy of the figures in Step 2 is really believable.

I understand the need for terms like "proto-mammal" and "stem-mammal"; I'm sure they are useful ways to classify and discuss these marvelous ancient animals.

The use of these terms kind of bug me though. The public at large still has that simplistic amoeba-fish-frog-lizard-possum-monkey-ape-human progression so ingrained that terms like "proto-mammal" may do more harm than good outside of a scientific discussion. It implies animals evolving toward something, like half-finished beasts. Which they weren't, as most readers of this blog probably know. They were well-adapted successful descendants and ancestors.

It's what I tried to illustrate with my drawing, above. The fallacy that the Permian synapsids were on their way to us.

Mike Keesey said...

Thanks! I did submit some sketches; I think they may be showing up later? (I am working on a Dimetrodon as well, but it still is not ready, sadly. I fear I've been spending too much time on stem-humans.)

Sorry to be a nitpicker, but it's my hobby. :)

"Stem-" is a great prefix that more people should use, IMO. Far from being a fad, the term "stem group" (or "Stammgruppe") has been around since Hennig as a way of referring to a paraphyletic group composed of all members of a total group which are not part of the corresponding crown group. It's a great, succinct, and accurate way to sum up what these animals are: closer to mammals than anything else living, but not actually mammals.

It's what I tried to illustrate with my drawing, above. The fallacy that the Permian synapsids were on their way to us.Ahh, I was wondering what was going on there. Now I see it. Interesting!

Zachary said...

Really wonderful stuff! I especially like the pack of gorgons attacking the pareiasaur! I'll be submitting a few simple pieces later. Just finishing up another project first...

Mike Keesey said...

Incidentally, lest it be thought that I'm nitpicking just for nitpicking's sake (not that I never do that) -- one reason I think it's important to get the terminology correct is because it can have a a very real effect on how we choose to illustrate these animals. I for one am rather tired of seeing Dimetrodon illustrations where it looks like a lizard. Not that Dimetrodon and squamates don't share certain plesiomorphies (sprawling posture, probably scales -- although those of lizards are fairly derived) but Dimetrodon is actually closer to us than it is to any lizard. Calling it a "stem-mammal" emphasizes that fact.

Case in point: a forked tongue on Cotylorhynchus seems really unlikely, given that forked tongues are a condition in one derived clade of squamates (including monitor lizards, Gila monsters, and snakes). Not that it couldn't have happened by convergence, but it seems unlikely, especially given the differing niches between the taxa in question and the fact that there are no other known cases of convergence (that I know of, anyway). Now, is someone likely to make that mistake if this is called a "stem-mammal", and not a "reptile"?

(BTW, other than the tongue, it's a really nice piece, possibly my favorite of these entries. Nice texture and very natural pose.)

Weapon of Mass Imagination said...

Well my two cents on the issue is that this group of animals has been grossly neglected when it comes to conveying to the general public.

They've never tweaked my fancy (and I think it is partially because you just don't read about them, except Dimetrodon), and so I've never tracked down technical literature on them (which from my brief attempts with this gallery, proved very hard to do anyway).

Someone needs to do the definative POPULAR level book on these guys.

As again I became attached to the term Proto mammal due to all my kids books calling them that. It can be hard to fight a long term affection like that.

Rachael said...

Forked tongued Cotylorhynchus or not, I'm just glad someone took the time to notice - thanks Mike!

Actually I put the forked tongue in because the Coty is said to have had teeth like an iguana.This lead to my imagination running haywire as Iguanas have slightly forked tongues. They also have a third 'eye' (light sensory)which I'm sure I read was a feature of synapsids? Also Coty is an earlier synapsid so i presumed less mammal like than the later ones.

Excuse my ignorance here. I'm learning as I go along!

Glad of any help and advice.

I'm very jealous of the amazing computer generated images. Wish I was more technically minded. I've only just managed to work out how to create a Blog...

Weapon of Mass Imagination said...

Rachael- I liked your approach on Cotylorhynchus. I've always thought of them as very convergent with monitor lizards. So in my mind your picture is preciously how I'd have approached them too...

Not that I'm an expert on them, and won't be surprised to find out that there were big differences (including the head size proportions, which I already knew)

I'm not sure about Synapsids having a third eye (I'm learning a ton about the stem mammals at moment too :P), but the Sphenodontia definately do. They are the primitive relatives of modern lizards (and by extension snakes... through, funny enough, monitor lizards).

On the only surviving Sphenodontia, the Tuatara, these third "eyes" appear as a weirdly coloured lump on the forehead of the young. As the adults grow up it hardens and gets covered over by other scales.

Mike Keesey said...

I believe the "third eye" is a plesiomorphy for amniotes, so, yes, it makes sense to include that. (I think.)

A forked tongue is possible, just not that likely, I think. Think about it this way: in initial designs for Jurassic Park they gave the "'raptors" forked tongues. Sound silly? Well, dromaeosaurids are more closely related to fork-tongued squamates than Cotylorhynchus is....

When reconstructing a member of a stem group (i.e., any extinct organism), there may be a mixture of: 1) character states which are also present in the crown group (in this case, mammals); 2) plesiomorphies retained in the extant sister group (in this case, reptilians); 3) plesiomorphies lost in the crown group and sister group, but retained in more successive outgroups (in this case, lissamphibians, lungfishes, coelacanths, etc.); 4) plesiomorphies lost in all extant forms; and/or 5) apomorphies which are not present in any extant form. The trick is in sorting these out as best as possible, given what evidence we have.

Mike Keesey said...

Someone needs to do the definative POPULAR level book on these guys.There's Synapsida by John McLoughlin, but it's a couple decades old by now....

Mike Keesey said...

As again I became attached to the term Proto mammal due to all my kids books calling them that. It can be hard to fight a long term affection like that."Proto-mammal" is vastly preferable to "mammal-like reptile", although I think "stem-mammal" or "stem group mammal" are better still.

Zach said...

I've always liked "non-mammalian synapsid," even though it takes awhile to say.

From the few technical papers I have on caesids, they really aren't that much like monitors at all--tiny heads, enormous bodies, oversized, herbivorous dentition. They may have been burrowers (enormous shoulder and arm muscles + wide forefeet). And the pineal eye ("third eye") is plesiomorphic for amniotes. It is ancestrally a light-sensitive lense but gets covered up pretty quickly by dermal and epidermal tissue. In most amniotes, it simply closes up.

Craig, like I said, I have a few other pictures on the way, including groups not included in this initial crop.

Mike Keesey said...

"Non-mammalian synapsid" is a nice, precise, accurate term, too. (It's pretty damn long, though.)

Mike Keesey said...

Weapons, did you mean "iguanas" instead of "monitor lizards"?

Weapon of Mass Imagination said...

Sorry all... I realized after submitting that last comment I did mean they looked like Iguanas and not Monitor Lizards...

Can you tell I've been doing a lot of research of Mosasaurs lately :P

Dinorider d'Andoandor said...

UFF! Great Art Gallery guys!