Wikipedia:WikiProject Palaeontology/Paleoart review/Archive 4

Metriorhynchids

• 
  Metriorhynchus and Geosaurus
• 
  Metriorhynchus, Geosaurus, Aspidorhynchus and Pholidophorus

I'm a user from the Dutch Wikipedia and occasionally I upload some images at Commons. I showed these to J. Spencer and he said I should put them at this page and let them be reviewed, so I did. I'd really like to hear if they are good enough or if they still need some improvements. I'd appreciate it if people could share their opinions on the drawings and maybe some comments about what could be done better. Thank you very much in advance! Kind regards, Joerim --82.169.6.44 (talk) 12:47, 5 January 2012 (UTC)

I forgot to give my references for the drawings. For the Geosaurus-reconstruction I used this drawing from Dmitry Bogdanov at Deviantart here. For the Metriorhynchus-reconstruction I used this 3D model from Robert Nicholls here. For the fish I used this book as a reference:

• Palmer, D. (2009). Evolutie. Historisch panorama van het leven op aarde. Tirion natuur, Baarn. ISBN 978 90 5210 782 0

Kind regards, Joerim --82.169.6.44 (talk) 12:59, 5 January 2012 (UTC)

Welcome! First, it might be problematical to only base drawings on other restorations, both from a copyright standpoint, but also because it makes them more like "third-hand" accounts, where it would be better to base them on either photos or draings of skeletons. As for the drawings itself, I tink they would had been a lot more barrel chested, when looking at skeletons like here[1]. The tail flukes seem to be too small as well. Especially the lower part[2]. FunkMonk (talk) 19:13, 5 January 2012 (UTC)

Rodrigues Starling

It became extinct recently, but the taxon is mainly known from sub-fossil remains, so it counts![3] Based on the comments here:[4] FunkMonk (talk) 04:05, 6 January 2012 (UTC)

I don't know much about birds, but it looks good from an anatomical standpoint. The posture seems a little strange, though. The body seems to be leaning back too far, giving me the sense that it is about to fall off the branch. Smokeybjb (talk) 19:56, 14 January 2012 (UTC)

Ah, I realised something was wrong with the weight, but I only see what now, the feet, therefore the point of gravity is too far forwards, since the legs are probably too long, how about this?[5] FunkMonk (talk) 21:38, 14 January 2012 (UTC)

Yep, looks better. Smokeybjb (talk) 01:03, 15 January 2012 (UTC)

Didn't get a response on the talk-page there, so just went ahead and coloured it. FunkMonk (talk) 06:31, 12 February 2012 (UTC)

Euryapteryx geranoides

I probably won't finish the above bird until Dysmorodrepanis comments, so here's a moa instead[6], I just started blocking the colours, but they will be based on this study[7] FunkMonk (talk) 07:06, 15 January 2012 (UTC)

I found this page on the reconstruction of three stout-legged moas (male, female, and chick) by the Museum of New Zealand Te Papa Tongarewa, written about here. Pictures of the finished models are here, though I have no idea why they're now labeling it Euryapteryx curtus. Anyway, might help.-- Obsidi♠n Soul 08:26, 15 January 2012 (UTC)

Heheh, look like muppets! The link about the reconstruction mentions it is supposed to be that genus, so thanks. I've changed some stuff accordingly, though there's still a lot to fix: [8] FunkMonk (talk) 15:42, 15 January 2012 (UTC)

Looks good. Isn't the neck too thick though? Upper part before it curves back up towards the head.-- Obsidi♠n Soul 17:20, 17 January 2012 (UTC)

You mean at the lowest point? Like this: [9] FunkMonk (talk) 10:51, 26 January 2012 (UTC)

The upper part. This area. But I'm thinking it's just because of the feathers? If that's the case, never mind I guess. :P -- Obsidi♠n Soul 05:45, 27 January 2012 (UTC)

Is this alright for the neck?[10] I think it was too front heavy too after looking at it again. FunkMonk (talk) 03:50, 29 January 2012 (UTC)

Nice feather details! :D And yep, better. -- Obsidi♠n Soul 12:03, 29 January 2012 (UTC)

Thanks, still needs work, but uploaded it anyway, will update it continuously. FunkMonk (talk) 10:50, 31 January 2012 (UTC)

Stratiotosuchus

Here's a work-in-progress profile of Stratiotosuchus I drew a very long time ago, based on the skull which can be found here (Figure 2). The new paper just reminded me of it, and I might try a full-body restoration some day. Smokeybjb (talk) 15:11, 16 January 2012 (UTC)

Looks good, is the size of the teeth based on anything? FunkMonk (talk) 07:47, 17 January 2012 (UTC)

Hm "In occlusion, upper and lower teeth alternate with the edges shearing past each other in a scissor-like fashion" <- what's that referring to? All teeth?-- Obsidi♠n Soul 17:18, 17 January 2012 (UTC)

I may have just guessed when I drew this, but the new paper says it has three premaxillary and five maxillary teeth. Looks like I was lucky! As for the shearing, the paper also says that the dentaries occupy "a mesial position relative to the upper teeth," meaning that they would be hidden under the teeth of the upper jaw. I'll change it to have some of the lower teeth show through the gaps, though. Smokeybjb (talk) 23:18, 17 January 2012 (UTC)

It'll be fun to see how you update it, since the old one is already coloured and stuff. FunkMonk (talk) 10:46, 24 January 2012 (UTC)

Lophorhinus

Decided to draw this therapsid because it has cool crests[11]. Based on the figures here. Smokeybjb (talk) 05:09, 17 February 2012 (UTC)

Looks cool, only thing I can see is that it seems like one of the upper incisors appears to be growing from the middle of the upper jaw, and they seem a little robust compared to the teeth in the diagram. FunkMonk (talk) 19:21, 18 February 2012 (UTC)

How's this[12]? Smokeybjb (talk) 04:12, 21 February 2012 (UTC)

I think it's good! FunkMonk (talk) 04:48, 21 February 2012 (UTC)

Tiktaalik

Temp

Mesh of Tiktaalik restoration redux.

Source files:

• File:Tiktaalik belgium II.jpg
• Skeletal
• File:Fishapod evolution.jpg
• Skeletal (posed)
• Diorama restoration
• 3d restoration

I'm probably going to render this in a submerged swampy environment with fallen tree trunks (Archaeopteris perhaps?) and lycophytes or something. Any ideas?-- OBSIDIAN†SOUL 04:35, 25 February 2012 (UTC)

Left a link to this in Wikipedia:Peer_review/Transitional_fossil/archive1. A user has left a comment about it there.

"Thanks for taking this on, Obsidian Soul. If you would like, I could try putting you in touch with an expert who is knowledgeable about the fish's anatomy in order to offer suggestions and critique your preliminary work. – VisionHolder « talk » 05:24, 25 February 2012 (UTC)"

--Harizotoh9 (talk) 05:53, 25 February 2012 (UTC)

Thanks, that would be nice, yeah.-- OBSIDIAN†SOUL 07:10, 25 February 2012 (UTC)

Looks great so far! One suggestion though, try a bit less extreme perspective. Most readers will see this in thumbnail size, where the perspective effects will make the animal appear out of proportion. Petter Bøckman (talk) 22:14, 26 February 2012 (UTC)

Heh, it's not posed yet at all. It's 3d, that's just the base mesh. The perspective will be much more natural in the final render with the textures, background scene and all. See my previous work on Laccognathus embryi above. Anyway do you happen to have a copy of Daeschler, Schubin, and Jenkins' original paper on it in 2006? If not, I'll request from resource exchange I guess. I might as well just have a look at it. -- OBSIDIAN†SOUL 22:23, 26 February 2012 (UTC)

I'll see what I can find at work tomorrow. Petter Bøckman (talk) 22:42, 26 February 2012 (UTC)

Thanks, and don't worry if you don't have access. The guys at resource exchange have yet to fail in providing sources. :) -- OBSIDIAN†SOUL 00:02, 27 February 2012 (UTC)

Updated. No scales yet, just the general form. I'm probably going to render this like this. With two individuals, one in the foreground perched on shallow rocks with the eyes just above water, and another in the background fully submerged and swimming in deeper water.-- OBSIDIAN†SOUL 19:22, 1 March 2012 (UTC)

I have found some useful sorces here. By the way what about showing it feding on small fish, since evry WP article on an elpistostegalian I've red so far suggests the diversefication of small fish in swampy regions as the mane facter behind the evolution of Tiktaalik like fish. Maybe we could make the neck a bit more noticeable by laterally bending it. Sari if I am increaseing your worklode to much.Aliafroz1901 (talk) 10:35, 23 July 2012 (UTC)

Operculum, gills and cleitrum

Fossil

Awesome! The only problem I see is that it looks like there's an operculum behind the head, which Tiktaalik didn't have. Smokeybjb (talk) 19:45, 1 March 2012 (UTC)

Are you doing this for a living, Obsidian? You should! I think the "operculum" is supposed to be the cleitrum bone. I guess we'll see more clearly when the scales come on. Petter Bøckman (talk) 21:02, 1 March 2012 (UTC)

Thanks. :) Smokeybjb, if you mean the second "curves" just before the pectoral fins, those are actually the cleithra etc. of the pectoral girdle like Petter said. Not too defined yet though, but I'm sculpting it some more. The first "curves" on the other hand are the posterior edges of the mandible and the rest of the skull. If you meant that, should I make the edges of it less sharper and more "merged" into the body? Anyway the skull shape also needs more work on it. Still a bit too polygonal. Petter: I wish, lol. Not a lot of demand for it in a 3rd world country.-- OBSIDIAN†SOUL 22:16, 1 March 2012 (UTC)

I don't think the edge of the skull should be too merged. This critter had gills. I would expect an Australian lungfish or perhaps a bichir would be a suitable approximation of how the gill cover looked, only Tiktaalik was a unique fish in that the cleitrum was not fastened to the skull. It would be able to bend it's neck, even displaying the gills, quite unlike any modern fish. Whether it actually would do that is another matter entirely. Gills are soft and delicate, and not something you want exposed in a tidal channel full of sharp branches. As for pose (and "action"), I quite like this one. Petter Bøckman (talk) 22:32, 1 March 2012 (UTC)

I can only say, nice work, Obsidian! FunkMonk (talk) 07:37, 2 March 2012 (UTC)

Not even halfway done yet though. :P -- OBSIDIAN†SOUL 12:04, 2 March 2012 (UTC)

I was referring to the second "curves". The cleithra in Tiktaalik are angled backward(see this paper), and in your model it looks like they go back but then sweep forward and connect to the skull table. Or am I misinterpreting this, and it's just part of the musculature? I don't know much about the soft tissue anatomy of fish, so correct me if I'm wrong. Smokeybjb (talk) 20:04, 2 March 2012 (UTC)

I think you may be right, something is fishy here. There is some bone going forwards to the skull, but it's less rounded than in the 3D mesh, see thumbnail. The muscle will obscure the underlying shape though. Petter Bøckman (talk) 20:21, 2 March 2012 (UTC)

Not quite. The cleithra are the ones at the sides, just forward of the pectorals. But nope, the ones at the top (the elongated thin section on the inner dorsal curve) are the anocleithra and supracleithra (labelled "suc" and "an" in here), both of which were also dermal and connected to the postparietal. -- OBSIDIAN†SOUL 20:38, 2 March 2012 (UTC)

Top illustration here.-- OBSIDIAN†SOUL 21:18, 2 March 2012 (UTC)

Ah, I didn't know about those. Looks good, then. Smokeybjb (talk) 21:25, 2 March 2012 (UTC)

Spiracle

Walking catfish

I've looked a bit more at the gill system in Tiktaalik. It had the straight up side-gills, but also a pair of spiracles high on the head, behind each eye. In this reconstruction you can see the spiracles well on the skull model, but it has been modeled as a pair of ears blocked off by tympanic membranes. As both Jennifer A. Clack and Michel Laurin agree both Panderichthys and the early labyrinthodnts had spiracles rather than ears, I think we can safely assume Tiktaalik had them too. Again, the bichirs are probably your best guide to how to model them, as the rest of of the skull is fairly similar (or as similar you will get with a modern animal) to Tiktaaliks. Petter Bøckman (talk) 08:11, 2 March 2012 (UTC)

Ah yeah, thanks. Spiracles added. I'll also probably use a coloration similar to that of bichirs.-- OBSIDIAN†SOUL 12:04, 2 March 2012 (UTC)

Not too sure about the coloration. If we assume (as Shubin does) that this critter was a fish eater who lived in shallow, murky water, then I think our best guess would be to find fish that live in much the same way and use it for a guide. I'm thinking the walking catfish would be a decent analogue. It too lives in poorly oxygenated water, breath with the swim bladder, has a wrap-around tailfin and uses the pectorial fins for propulsion and will if necessary leave water to catch food (see picture). Unfortunately, such fish is usually rather drab without much markings (but zoom in on the head!), on the plus side, it will let your 3D work really stand out! Petter Bøckman (talk) 12:23, 2 March 2012 (UTC)

Easier too! LOL. Drab coloration would mean I wouldn't have to worry about finicky details. And I'm quite familiar with the walking catfish (native here, with the local name pantat), we used to farm them. :) Been wounded by the sharp spines hidden in their fins a few times. -- OBSIDIAN†SOUL 13:37, 2 March 2012 (UTC)

Fins

Acantostega for reference

I'm really looking forward to seeing your finished work. If the temporary picture is anything to go by, I think we may have the finest pictorial reconstruction there is!

One thing though: Are the fins a tad small? I'm mainly thinking about the pectorial fins, the size of the pelvic fins are really anyones guess. The pectoral fins on the cover of "Your inner fish" seems quite a bit larger. The elpistostegalians typically used their pectorial and pelvic fins as main propulsion organs, rather than the tail. I see you have given it a quite reduced tail, but if it was to function as a predator, it would need fins able to accelerate quickly. Since you are familiar with the walking catfish, it may perhaps serve as an indicator of the size of the fins? It seem to have more of a tailfin than Tiktaalik, so Tiktaalik should have larger pectoral fins than the catfish. That is, if Tictaalik actually were an active predator... Petter Bøckman (talk) 14:15, 2 March 2012 (UTC)

Hmm true. I'll bulk it up a bit. Was basing it on line reconstructions. Also, I think it needs to be positioned more ventrally. As for the tail, it is actually a bit larger than suggested by the authors. Its shape, I guess, was based on comparison with the tails of bracketing groups. Between Panderichthys and the earliest tetrapods AFAIK, midline fins have all been lost except for the caudals.-- OBSIDIAN†SOUL 15:21, 2 March 2012 (UTC)

As you can see, I'm not a millimeter man, I'm a biologist and is looking for having a critter that works. As far as I can tell, we don't really have a tail. So no, we don't really know what size it actually was, and we have a bit of leeway. The fin ray part of the pectorial fins is about as long as from between the eyes to the back margin of the skull according to this cast of the holotype. Phylogenetic bracketing is all fine and dandy, but evolution seldom proceed linearly. The reconstructions I've seen of Acantostega shows it with a bigger tailfin than Panderichthys. I'll trust you with doing the actual reconstruction, just remember the critter would have to swim, either with the pectorial/pelvic fins or with the tailfin. Petter Bøckman (talk) 19:45, 2 March 2012 (UTC)

In addition to making the limbs more robust, I guess I can make it more like that of Acanthostega? Not expanding the actual rays of the fins, but making the tail itself laterally flattened like here? -- OBSIDIAN†SOUL 20:37, 2 March 2012 (UTC)

Here's the proposed tail shape (outlined in blue). Also included is a labeled breakdown of the dorsal pectoral girdle. Spiracles are also already modeled in in that.-- OBSIDIAN†SOUL 21:13, 2 March 2012 (UTC)

Tiktaalik, relative fin lenght

The new flatter tail seems good to me. I don't know if you need to stretch the tailfin so far forward though. The larger size fin in Acanthostega could be to compensate for the loss of fin rays. The hight of the tail fin would probably vary. I suppose Tiktaalik, like all fish, had the ability to raise or lower the fin at will. The pectoral fins (not the stalk, but the fin-ray part) seems it needs to be longer. Have a look at this simple comparison. The scale bars are of the same length. Petter Bøckman (talk) 21:10, 5 March 2012 (UTC)

Gotcha, will try stretching the pectoral rays some more.-- OBSIDIAN†SOUL 21:34, 5 March 2012 (UTC)

I'm really excited over this, looks forward to seeing the result! Petter Bøckman (talk) 14:21, 7 March 2012 (UTC)

insidentaly I recently made a post at talk:Tetrapod. You could try useing the reconstruction of ichthiostega's lims as a gide to modifying the fins.Aliafroz1901 (talk) 11:27, 22 July 2012 (UTC)

Jesus, I've completely forgotten about this after intervening shite that made me quit editing for a while. I'll dig up the files and resume working on it.-- OBSIDIAN†SOUL 12:38, 22 July 2012 (UTC)

That would be very much appreciated! Glad to see you back in the saddle too! Petter Bøckman (talk) 10:53, 23 July 2012 (UTC)

Neck

If our Tiktaalik article is correct, it "also lacked a characteristic that most fishes have—bony plates in the gill area that restrict lateral head movement. This makes Tiktaalik the earliest known fish to have a neck, with the pectoral girdle separate from the skull." Lateral (anatomy) implies sideways movement, distinct from fishes which must move their whole body to move their head. Shubin's Your Inner Fish pp. 22–24 is clear that Tiktaalik was distinguished from fishes by having a neck and being able to move its head independently, but these pages of his book don't indicate whether the movement was lateral. Shubin also emphasises that they had "almost crocodile-like heads—flat, with the eyes on top", that may be worth emphasising by the viewpoint. This sketch is terrific, hope the end result has something of that character. . dave souza, talk 14:42, 17 May 2012 (UTC)

p.s. Jason P. Downs, Edward B. Daeschler, Farish A. Jenkins & Neil H. Shubin (16 October 2008). "The cranial endoskeleton of Tiktaalik roseae". Nature. 455 (7215): 925–929. doi:10.1038/nature07189. PMID 18923515.{{cite journal}}: CS1 maint: multiple names: authors list (link) seems to have discussed this point, as illustrated in this news item and this image linked from the press release. . . dave souza, talk 15:01, 17 May 2012 (UTC)

The cleitrum bone (the primitive shoulder girdle) in fish is connected to the skull above and below, and function as a bony hind margin for the gill opening. This of course restricts movement of the head. In Tiktaalik, the cleitrum was "free". It was not fastened to the skull at the lower end, but it would still have to be fastened to something at the upper end, or it would not be able to function as a stable anchoring for the leg-like fins. This mean that whatever Tiktaalik could do, the most obvious difference from other fish was the ability to tip the head up. Shubin writes (Your inner fish) that really the only thing the pectoral fins were suited to was a push-up like movement. This sounds a bit silly, but combined with the tipping head it sounds like something a land-going fish would do to assert dominance. Mudskippers do the same thing, so it's not a much a stretch of imagination to Tiktaalik having "push-up contests" showing off a brightly coloured throat along Devonian river banks. Petter Bøckman (talk) 07:20, 31 July 2012 (UTC)

Sorry I got bogged down expanding (and arguing about) another article again. Thanks for the links dave, and yep aiming for that definitely. I also just received my tablet, which will help me detail the environments some more without relying on 3d, though I'm still adjusting to it, LOL. As for mudskippers, the bulk of Tiktaalik would probably have made it harder for them to remain moist on land though. It was probably simply an ambush predator adaptation in shallow water, like in crocodiles. The throat is a nice idea though, heh.-- OBSIDIAN†SOUL 08:19, 31 July 2012 (UTC)

Prorubidgea

Here's a sketch of the head[13], I'd like to draw the body as well, but haven't been able to find an image of the skeleton... A skull cast can be seen here: http://fossils.valdosta.edu/fossil_pages/fossils_per/t38.html FunkMonk (talk) 01:47, 22 March 2012 (UTC)

You could try using Gorgonops as a guide. Petter Bøckman (talk) 06:05, 22 March 2012 (UTC)

Thanks, do the proportions fit? FunkMonk (talk) 17:42, 3 May 2012 (UTC)

Gorgonopsian relationships are a bit messy but I think Prorubidgea is more closely related to Lycaenops than Gorgonops (there's a review of gorgonopsians here with more info about this). Lycaenops might be a better guide, but since Prorubidgea is only based on skulls I don't think it matters much what you use for proportions. Smokeybjb (talk) 18:03, 3 May 2012 (UTC)

Like the above section, I've neglected this guy for quite a while, so here's an update I just whipped out: [14] Is such a pose plausible? It was (obviously) based on a dog. FunkMonk (talk) 03:23, 15 August 2012 (UTC)

Lycaenops skeleton

It would probably be possible, but I don't think it would be very comfortable for the animal. If you consider the Lycaenops (right), you see the vertebrae passing in a very even curve over the hip. This imply the whole hip arrangement was rather stiff and "reptilian". The tylacine, who had a somewhat similar arrangement, did sometimes sit (see eg here), but mostly they would be laying down or standing. The forelegs on the Lycaenops also splayed somewhat out sideways (still does in anatomically primitive mammals), making the dog-type sitting position energetically demanding. The reason a dog sits like it does is because it can "lock" the forelegs and thus expend very little energy while retaining the same overview as if it was standing. The position of the animal you have drawn would make sense if it was laying eggs though.

I think the whiskers you have drawn on are plausible, but I'm not sure about the rug over the shoulders. A pelage is not likely to have evolved other than in the small, next-to-mammal cynognaths. While Prorubidgea may have had whiskers in more places that the head, it is not likely to have them on the shoulders. The parts of the body exposed to most wear, like feet and tail, were likely scaly, like in modern opossum and rodents. Petter Bøckman (talk) 07:22, 15 August 2012 (UTC)

Thanks for the thorough response! I was going to change the posture, but then I realised I've never actually seen an image of a gorgonopsian laying eggs, so perhaps that would be a novel and interesting thing to do instead (we have tons of images of gorgonopsians sitting or walking)? Would it lay them in a nest or a burrow? Or just on the ground? FunkMonk (talk) 14:16, 15 August 2012 (UTC)

That is a good point, I don't think we have any pictures of a specifically female therapsid at all! I don't think there are any finds suggesting gorgonosians burrowing, they would have been a bit on the big side, modern mammals of that size usually don't burrow. Neither do mammals build nests much. I would suggest a very simple nest, ostrich style. Petter Bøckman (talk) 15:11, 15 August 2012 (UTC)

Do we know what their eggs could had looked like? FunkMonk (talk) 19:07, 15 August 2012 (UTC)

Monotreme eggs are soft and leathery, the same goes for squamate eggs. It's really only archosaurs who have hard-shelled eggs. A few papers have suggested lactation originated as a way to keep the eggs moist, so I would expect them to be shiny and wrinkly. The hip opening of therapsids looks kind of smallish, so I guess th eggs were quite small, monotreme eggs certainly are. Petter Bøckman (talk) 19:46, 15 August 2012 (UTC)

Still on the sketch stage, does this look plausible?[15] FunkMonk (talk) 02:21, 17 August 2012 (UTC)

I don't think animals of that size and mass actually sat down on their eggs to incubate them though. It looks like it would crush them. Wouldn't a mound of decaying leaves be more likely? That said, I'm leery of portraying eggs, as I think nobody has ever found undisputable therapsid eggs? -- OBSIDIAN†SOUL 03:23, 17 August 2012 (UTC)

It was supposed to show the process of laying them, of course not the best angle to show it (maybe the hind part is too close t the ground?), as for portraying the eggs themselves, you mean that we don't know if they did lay eggs? FunkMonk (talk) 03:30, 17 August 2012 (UTC)

I think so, yeah. I can't find any mentions online of actual fossil Permian therapsid eggs. Not even of cynodonts. As for the lactation theory (which I think was also referring to cynodonts rather than gorgonopsids, maybe even exclusively to Mesozoic cynodonts), it would mean the eggs would more likely be situated directly under the belly/chest area and the animal either laid over them or curled around them (when incubating them I mean, no idea how they laid them). Mammary glands developed around that part after all, not the butt, heh. Mesozoic mammalian ancestors also had unique epipubic bones which may have served as attachments for pouches, but gorgonopsids were Permian and it's unknown if they too had pouches.-- OBSIDIAN†SOUL 03:41, 17 August 2012 (UTC)

I mean, we do know they laid eggs, but from phylogenetic bracketing rather than fossil remains it seems. The Google preview of a 1997 paper (second result) says "...Unfortunately, fossil eggs are rare in the Paleozoic (amniote eggs have not been discovered)...". Can't access the paper though. The 2012 book Earth Before the Dinosaurs also says "no amniote fossil egg has been found in the Paleozoic layers".-- OBSIDIAN†SOUL 03:57, 17 August 2012 (UTC)

Heh, so showing the eggs would be fine? Someone has to do it! The "random" placement of the eggs is because I assume it would only position them after laying them all, I think I've seen footage of animals doing this. FunkMonk (talk) 05:10, 17 August 2012 (UTC)

I personally don't know, haha. I mean, they could've actually still laid their eggs in water for all we know. Or buried them in sand like crocodilians. Dunno, Petter might be a better judge if it's justifiable. ^-^ -- OBSIDIAN†SOUL 05:42, 17 August 2012 (UTC)

He was actually the one who suggested it a few comments up, so I guess it's ok... FunkMonk (talk) 05:53, 17 August 2012 (UTC)

I think the eggs you have drawn look good. Perhaps not that many though. The pups would have to be fed, possibly for a time on milk alone. If we assume a rather ineffective lactation delivery system like in monotremes, a large clutch would be difficult to raise. I'm speculating, but 4 eggs top perhaps? As for the lactation, a nice article on it can be found here. It argues lactation was common from "early synapsids" on, which I read as at lest the whole of Therapsida.

One note on posture: Even with the larva-like young of marsupials, birth seems to be quite hard. Perhaps she should arch her back a bit more, show some muscle tension on the legs and a perhaps open her mouth a bit? Petter Bøckman (talk) 13:22, 20 August 2012 (UTC)

I abandoned this for a while, just tried to implement a few of the changes proposed above[16], are they even noticeable? FunkMonk (talk) 00:08, 2 October 2012 (UTC)

With grey tones. I'll colour it later. FunkMonk (talk) 06:32, 17 October 2012 (UTC)

Anyone know what species it is? http://fossils.valdosta.edu/fossil_pages/fossils_per/t38.html FunkMonk (talk) 06:35, 17 October 2012 (UTC)

Neat! Looking forward to the finished picture! Petter Bøckman (talk) 13:23, 17 October 2012 (UTC)

Crocodylomorphs

Here are some sketches of some more random crocs: Junggarsuchus[17] based on this figure, Baurusuchus albertoi[18] based on the figures in this article (unfortunately there's no skeletal and I had to scale up and arrange the bones, so I'm not certain on the proportions), and Rimasuchus[19] based on the diagram here. The snack is supposed to be Homo habilis. Not just my imagination, it's inspired by the presence of crocodilian bite marks on some hominid bones from Olduvai Gorge (although the marks might now be attributed to Crocodylus anthropophagus... I'm not sure). Smokeybjb (talk) 05:42, 22 April 2012 (UTC)

Eh, Junggarsuchus is from the Jurassic, Homo habilis lived just a few million years ago. The type of small, light, running crocks like Junggarsuchus were very much a a feature of the pre-dinosaur or early dinosaur world. The only type of crocks to ever have sunk their teeth into hominin flesh are of the regular modern kind. Petter Bøckman (talk) 20:19, 22 April 2012 (UTC)

The one with Homo habilis is Rimasuchus. Smokeybjb (talk) 20:44, 22 April 2012 (UTC)

Ha, now my Rimasuchus is Crocodylus thorbjarnarsoni[20]. Smokeybjb (talk) 16:58, 3 May 2012 (UTC)

Cool, hadn't seen this until now. Perhaps the front legs of the Baurusuchus are a bit large compared to the hind legs? And would the tail be that flexible so close to the "root"? FunkMonk (talk) 17:41, 3 May 2012 (UTC)

Good point, I'll fix that. Smokeybjb (talk) 17:53, 3 May 2012 (UTC)

How is it now? I made the hind limbs thicker and the front legs a bit shorter, but not by much since I'm pretty sure the proportions are correct (if only there were measurements in the paper so I could be certain!). Smokeybjb (talk) 20:23, 13 May 2012 (UTC)

Looks good! FunkMonk (talk) 10:53, 25 May 2012 (UTC)

Clepsydrops

Is File:PSM V73 D564 Skeleton of clepsydrops.png accurate? I assume that it is not, given the date, but it is in use on other Wikipedias. If it's inaccurate, can you give a brief explanation of why so that I can tag the file page on commons? Thanks, Calliopejen1 (talk) 13:43, 27 April 2012 (UTC)

Clepsydrops is now classified as an ophiacodont, so I doubt it had a sail. I think this picture might be a species of Clepsydrops like C. limbatus or C. natalis that since been placed within Dimetrodon, since the article mentions that this Clepsydrops specimen definitely had a sail. Smokeybjb (talk) 21:03, 27 April 2012 (UTC)

Seems it's from Willbarger County, Texas[21][22], don't know if that helps. And this restoration almost seems to be based on the skeletal: [23][24] FunkMonk (talk) 17:24, 3 May 2012 (UTC)

Microposaurus

Here's a rough photoshop drawing of Microposaurus averyi from this paper in the new JVP issue. Since only the front of the skull is known, the length of the skull behind the eyes is guesswork. Smokeybjb (talk) 03:19, 13 May 2012 (UTC)

The paper says it is from the Trematosaurinae subfamily. This would indicate it was likely marine with a crocodile-like proportions of the skull. Petter Bøckman (talk) 07:13, 13 May 2012 (UTC)

Most of the skull is already there in the specimen that's described in this paper, and the snout is definitely very short, not like a crocodile (most trematosaurines have short snouts, while lonchorhynchines have long snouts). I just now looked at Damiani (2004)[25] which describes the skull of Microposaurus casei, and it turns out the back of the skull is much longer than the snout, so I'll adjust my proportions. Smokeybjb (talk) 17:24, 13 May 2012 (UTC)

Here's a new version[26]. Smokeybjb (talk) 18:43, 13 May 2012 (UTC)

Good grief, what an ugly animal! I look forward to seeing the finished picture! Two pints though: 1) You have given the critter a tympanum covering the otic notch. This is in accordance with conventional wisdom, but research on the stapes in early tetrapods, indicate all labyrinthodont grade tetrapods were death. Whether they had open spiracles or the opening were simply closed over is anyones guess, see here. 2) Your critters appear to be sitting in a rock, basking. While this again is a conventional way of showing them, amphibians generally do not bask, particularly not large ones. To effectively warm up a large body you will need a high surface temperature. This will cause moisture in their skin to evaporate, actually lowering the temperature. Anyway, amphibians don't like drying out. While it quite probably could climb up on a rock, it would both reproduce and hunt in water (the teeth looks like those of a fish-eater), so there would be very little reason for it to go on land. Petter Bøckman (talk) 20:03, 17 May 2012 (UTC)

Hm, I was guessing that the tympanum or a similar membrane would have developed in temnospondyls before the hearing system would have been functional, but that's probably not a valid assumption now that you point it out. Microposaurus definitely wouldn't have had it because it had a lateral-line system to do the job of detecting vibrations. Laurin and Soler-Gijón (2006) discuss tympana here and the closest relative of Microposaurus they mention is Dutuitosaurus. Since they suggest Dutuitosaurus had a spiracle, I'll probably give Microposaurus a spiracle too. On the other hand, at least some temnospondyls like Dendrerpeton and Doleserpeton had tympana (see here and here), so I'm not going to change all my temnospondyl illustrations just yet! As for your second point, I'll put it in water, but the skin of temnospondyls was covered in small scales, not exactly the same as modern lissamphibians. Wouldn't that mean they could spend some time on land? I still agree with you though that aquatic forms like Microposaurus probably wouldn't have done this. Smokeybjb (talk) 21:10, 17 May 2012 (UTC)

Thanks for the links, these articles will come in handy! Anyway, skin respiration in labyrinthodont grade tetrapods is an interesting topic on it's own. As a palaeo-reconstructor, I think you'll find this interesting. Amphibian scales are not the watertight reptilian horny type, they are quite vascular bony nodules in the skin. Modern day Caecilians actually have scales, it does not stop them from drying up. The only labyrinthodonts likely to have had a horny epidermis are the advanced reptiliomorph lot (Seymouriamorpha and Diadectomorpha). Petter Bøckman (talk) 21:30, 17 May 2012 (UTC)

OK, I updated, colored and uploaded it. How's it now? Smokeybjb (talk) 20:41, 26 May 2012 (UTC)

Oh, nice! Petter Bøckman (talk) 20:12, 28 May 2012 (UTC)

Archeopelta

Here's a rough photoshop sketch of Archeopelta.[27] It's based on Doswellia since Archeopelta is mostly distinguished from Doswellia by a few small differences in the skull. Most of it is based on the information in Weems (1980) (here) and the skeletal in that paper (which was also used in the Archaeopelta paper[28]). I gave it an unusual posture to show off the boxiness of the torso. Smokeybjb (talk) 18:52, 23 June 2012 (UTC)

Hah, weird! From this skeletal[29], it appears the tail width should maybe be more drastically tapered? FunkMonk (talk) 19:51, 23 June 2012 (UTC)

How's this?[30] That's the same skeletal as the one in the paper. Smokeybjb (talk) 21:21, 23 June 2012 (UTC)

Looks better, I think. FunkMonk (talk) 03:31, 24 June 2012 (UTC)

Albertonectes

Here's Albertonectes[31], the extremely long-necked plesiosaur, based on this picture of the skeleton. The size of the head is guesswork. Also, the paddle motion might not be right: I'm not sure if the back flippers would bend that much on the down stroke, and I'm not wheteher the up and down strokes were simultaneous for both the front and back flippers or if they alternated like I've shown. Smokeybjb (talk) 05:32, 7 July 2012 (UTC)

Maybe the head appears a bit too big, compared to for example Thalassomedon (compare with flipper size)?[32] Incidentally, David Peters of all people seems to have made a skeletal which doesn't look too bad, proportion-wise...[33] FunkMonk (talk) 06:24, 7 July 2012 (UTC)

That's what I was worrying. Does this look right[34]? Smokeybjb (talk) 17:40, 7 July 2012 (UTC)

Good! It appears the neck would taper a bit more towards the skull, it looks quite even in your reconstruction, but perhaps it's due to soft tissue? As for the fin action, I'm not sure if there is consensus on this, but it should certainly be checked out... Perhaps this can help: http://www.oceansofkansas.com/swim-sim.html FunkMonk (talk) 17:43, 7 July 2012 (UTC)

Hahah, just looked at the link, the experiment looks almost like a joke... FunkMonk (talk) 17:43, 7 July 2012 (UTC)

Yep, I saw that while I was looking for more info on the fins. This page[35] outlines the different ways of swimming but says alternating and synchronous strokes are still being debated. But then there's this more recent paper[36] favoring synchronous strokes, so I guess I'll be changing it. I've shaved the neck down just a bit here[37], but I think the throat would still take up some of that extra room toward the skull. Smokeybjb (talk) 18:26, 7 July 2012 (UTC)

I just noticed that stills from that pool video are in the paper. Funny! Here's a new version[38] with the semi-synchronous motion favored in the paper. Smokeybjb (talk) 18:31, 7 July 2012 (UTC)

I think we have a winner! But would the tail had been so thick at the base? FunkMonk (talk) 17:43, 7 July 2012 (UTC)

Hm... I agree, looks too fat. I must have been thrown off by the strange posture of the skeleton. Is this better[39]? Smokeybjb (talk) 19:29, 7 July 2012 (UTC)

Yup, I don't think I have anything more to add... FunkMonk (talk) 19:38, 7 July 2012 (UTC)

Done! The neck looks even more ridiculously long at thumb scale. Smokeybjb (talk) 23:14, 7 July 2012 (UTC)

Heheh, that animal will just look implausible in any restoration. FunkMonk (talk) 23:46, 7 July 2012 (UTC)

Echinerpeton

Here's Echinerpeton,[40] an early synapsid that looks sort of like a cross between an ophiacodontid and a sphenacodontid, although its relationships are fuzzy and it could be neither. Based on the scrappy remains figured in this paper. The head is generalized basal synapsid, not based on anything in particular. Smokeybjb (talk) 04:02, 14 July 2012 (UTC)

Compared to this[41], it seems the eye wouldn't fit into the orbit. Maybe a at least half as small would be better? Did any of its relatives have sclerotic rings? That would settle it. FunkMonk (talk) 07:31, 14 July 2012 (UTC)

The paper says Echinerpeton was very small and that the bones are only a few centimeters long, so I'm assuming it had very different proportions compared to something big like Ophiacodon which was over a meter long. I'll try to find out if there's any juvenile specimens of ophiacodontids or sphenacodontids around which might give a sense of skull proportions. Smokeybjb (talk) 16:25, 14 July 2012 (UTC)

Nikkasaurus had huge eyes, and is apaprently preserved with sclerotic ring. Since the only the part of the eye within the inner ring would be externally visible[42], it seems Dimitry bogdanov's restorations has a bit too large eye.[43] Echinerpeton's eye probably wouldn't be much larger, no? Then again, that skeletal is also from Reptileevolution, and who knows if David Peters hasn't added the stuff about the sclerotic ring to the article, is there independent reference to this? Seems this paper has some mention of sclerotic rings: https://doi.org/10.1134%2FS0031030108090013 FunkMonk (talk) 16:32, 14 July 2012 (UTC)

Good point. The paper shows the sclerotic rings in Nikkasaurus, so at least Peters didn't make this part up. I can't find any ophiacodonts/sphenacodonts with sclerotic rings, but if they're present in Nikkasaurus, they were probably also present in earlier synapsids. Does this look right?[44] Smokeybjb (talk) 16:57, 14 July 2012 (UTC)

I think it "feels" more natural... FunkMonk (talk) 17:07, 14 July 2012 (UTC)

It looks really nice, but I think it should have a hint of scales, at least on the feet and other parts exposed to wear. The naked skin gives it a somewhat amphibian look. Petter Bøckman (talk) 09:38, 31 July 2012 (UTC)

Temnospondyls

Experimenting with line drawing, since it's ten times faster than what I usually do:

• 
  Arcadia myriadens
• 
  Banksiops townrowi
• 
  Boreopelta vavilovi
• 
  Broiliellus olsoni
• 
  Broomistega putterilli
• 
  Cryobatrachus kitchingi
• 
  Deltasaurus kimberleyensis
• 
  Eolydekkerina magna
• 
  Isodectes obtusus
• 
  Jammerbergia formops
• 
  Lapillopsis nana
• 
  Muchocephalus muchos
• 
  Nanolania anatopretia
• 
  Neldasaurus wrightae
• 
  Rhineceps nyasaensis
• 
  Rotaryus gothae
• 
  Rubeostratilia texensis
• 
  Trucheosaurus major
• 
  Vigilius wellesi

Most of these are based only on skulls, so the body proportions are only guesses. I can't get external links to work in galleries for some reason, so here are links to the papers they're based on:

• Arcadia
• Banksiops
• Boreopelta
• Broiliellus
• Broomistega
• Cryobatrachus
• Deltasaurus
• Eolydekkerina
• Isodectes
• Jammerbergia
• Lapillopsis
• Muchocephalus
• Nanolania
• Neldasaurus
• Rhineceps
• Rotaryus
• Rubeostratilia
• Trucheosaurus
• Vigilius

Smokeybjb (talk) 04:47, 27 July 2012 (UTC)

Looks good! Will you colour them? FunkMonk (talk) 10:30, 27 July 2012 (UTC)

I might for some, but I'm keeping most of them simple because they're easier to churn out. Hopefully I can provide illustrations for a lot more critters this way, especially the obscure ones. I'll still be making some in color, though! Smokeybjb (talk) 19:14, 28 July 2012 (UTC)

These are gorgeous! -- OBSIDIAN†SOUL 08:08, 31 July 2012 (UTC)

Oh, these are nice! Petter Bøckman (talk) 09:38, 31 July 2012 (UTC)

Question: Have you used phylogenetic bracketing for the body proportions of any of these? If so, it could work nicely as an illustration in the phylogenetic bracketing article. Petter Bøckman (talk) 18:43, 5 August 2012 (UTC)

Not really, but I could make one that is. I'll probably use Mastodonsaurus and Paracyclotosaurus for bracketing, since almost their entire skeletons are known. Smokeybjb (talk) 23:52, 5 August 2012 (UTC)

That would be grand! The black/white line drawing style would do nicely, it's the proportions I'm looking for, not a full environmental reconstruction. Petter Bøckman (talk) 06:53, 6 August 2012 (UTC)

Here's Stenotosaurus[45] with Mastodonsaurus[46] and Paracyclotosaurus[47] on a simple cladogram to show the bracketing. The silhouettes are meant to compare their sizes. What do you think? Anything I should change? Smokeybjb (talk) 20:08, 10 August 2012 (UTC)

Perfect, couldn't as for a better figure! Petter Bøckman (talk) 20:28, 10 August 2012 (UTC)

Alright, it's uploaded. I'll try to make a vector version soon. Smokeybjb (talk) 21:00, 10 August 2012 (UTC)

Diandongosuchus

A new one! Here's Diandongosuchus[48] based on the skeleton shown in the paper.[49] More scales and scutes to come... Smokeybjb (talk) 02:56, 29 August 2012 (UTC)

Looks cool, two issues come to mind; from what I can see, the right leg would have a hard time getting into that position without breaking the foot, seems to be bending the wrong way. The right eye seems to be slightly larger too. I've drawn what I mean here: [50] FunkMonk (talk) 03:03, 29 August 2012 (UTC)

Hm, I was trying to have the leg bend a bit downward as it went out to the side (femur pointing down and back with the knees bent so the lower leg goes back up), but I guess it didn't work. How's this?[51] Smokeybjb (talk) 03:29, 29 August 2012 (UTC)

If the femur bent downwards in that manner, wouldn't the "palm" of the foot face more upwards, instead of inwards? I assume it couldn't rotate too much? In any case, I think the new version looks flawless. FunkMonk (talk) 03:34, 29 August 2012 (UTC)

You're right. And now that I think about it, the legs probably wouldn't hang down much while the animal was swimming; otherwise drag might be a problem. Smokeybjb (talk) 03:44, 29 August 2012 (UTC)

Absolutely beautiful work! I guess it is a bit late to change things now, but would it be an idea to have the legs more flat along the tail when swimming, as in modern crocodiles? Petter Bøckman (talk) 07:56, 18 September 2012 (UTC)