Showing posts with label palaeoart. Show all posts
Showing posts with label palaeoart. Show all posts

Thursday, 5 July 2018

'A Disarray Of Palaeoart' - A New Book By Me!

2017: Daily Doodles FOR TWO FLIPPIN' MONTHS!


Every November, doodlers from across the three double-ues go crazy producing palaeo-themed illustrations for DrawDinovember, which is, in effect, the palaeo world's very own Inktober. For those not in the know, Inktober is a month-long daily-doodle event. Doodlers upload their ink artwork to the internet, complete with "#inktober". DrawDinovember is similar, but requires something a little more dinosaurian. Or just palaeontological.

It's pretty loose, and no one's standing guard. Overseeing it is its creator, Brynn Metheney, who lurves her dinosaurs – but she's groovy about it all, and offers hearts and retweets via the official Twitter account, @DrawDinovember. (By the way, you look at what she gets up to here!)



Anyways, I did do doodles last October, though it has to be said that my Inktober offerings—it's starting to sound like some Romano-British pagan cult—were not all of a palaeontological flavour. In fact, most of them were shitty doodles of Daleks and spaceships because, for some reason, I was nine years old for much of October. (It happens, sometimes.) But I fared much better for November, and I ended up with a shedload of doodles of various styles and qualities.

Hmm... What to do with all those sketches.

A book happened!


So, a few of you will be aware that I recently loosed A Disarray Of Palaeoart, so named because there's no particular thread tying everything together. It kicks off with a great foreword from those wonderful bods at Love In The Time Of Chasmosaurs (which was exciting for me, and I'm still buzzing off it), and then there's a false start with a non-palaeo image (but who doesn't like a hornbill?). There's a pretty eclectic mix of palaeo 'strations and styles, with each image accompanied by a chunk of text, ranging from some deep quasi-scientific musings to early-20th-century-style nonsense poetry. ('Nonsense poetry' is a term that bad poets hide behind.)

My youngest, Alice, helping with the photography for the book's cover. (Photo: G. Monger)

The poetry was inspired by the 1913 book, The Google Book, by Vincent Cartwright Vickers, a renowned economist and Fellow of the Royal Zoological Society. Vickers was a keen naturalist and it's clear that if he leaned in any particular direction, it was one that was feathered. To summarise, The Google Book is a collection of ink-and-watercolour illustrations of fictitious birds in a fictitious land, complete with verses and descriptions. It's wonderfully whimsical, but its 1913 release was extremely limited, apparently to only a hundred or so copies. Fortunately, in 1979, Oxford University Press published a new edition, and my parents had the good sense to snag a copy.

"Have you seen the Lemonsqueezer, feeding Herbert and Louisa?" From The Google Book by V C Vickers.
(Public Domain)
So that's The Google Book, and in terms of inspiration, only accounts for about 6 of the 114 pages. But it's a brilliant little book and it's worth a shout-out. There aren't loads of them out there, but eBay typically has a couple from time-to-time.

The rest of the book is harder to characterise, basically because it's all over the place like a toddler's breakfast. Don't worry – it's meant to be. It covers pop culture, local history, made up folklore, and straight and speculative palaeontology. Whatever people make of it, I hope that they see it as fun. As one of my day-job customers commented yesterday (in a thick Lancashire accent), "I'm not gonna lie, I didn't understand all of it – but it's got humour in it!"

It wasn't all plain sailing in the Mesozoic. Bad things happened. Maybe not the ichthyosaur thing, but probably everything else. Left to right: A pliosaur crashes into Leedsichthys, resulting in the death of both; Protoceratops boots Velociraptor down a sand dune; An ichthyosaur has the wrong baby: awkward conversation ensues; a sauropod montypythons a pterosaur; a baby Pterodactylus wears all the floof.

The text-to-imagery ratio is probably around 50:50. It's all very well shovelling a bunch of doodles into a book, but an image-only affair might come across as lightweight and a little self-absorbed. So I wrote a load of stuff in a style not-too-dissimilar to this blog. And when asked about 'technical speak' by that gentleman mentioned earlier, I explained that if I worried too much about writing for any particular group, I'd probably wind up dumbing it down, and no one wants that. I'm not an academic, so I fully expect that academics will get that if they read this. But kids are clever, and if they meet a word or phrase which doesn't make sense, they know how to find out what it means. And if I've made a boo-boo, kids will be the first to let me know. And that will be the ultimate compliment.


A Disarray Of Palaeoart is available to buy here, priced £10 plus carriage.

Tuesday, 29 May 2018

Are We Shrink-Wrapping Ichthyosaur Tails?

(Don't start with a disclaimer... DON'T START WITH A DISCLAIMER!)

DisclaimerI'm not trained in palaeontology or fluid mechanics, but after recently illustrating a few ichthyosaurs for a project, I wondered if I was reconstructing their tails too conservatively. I had a poke around the internet and tried to translate it into some coherent thoughts. A water tunnel, tame engineer, and unlimited access to ichthyosaurs would have been useful, but in the absence of all of that, I just had fudge it. And fudge it I did.

The Current Popular Look For Ichthyosaur Tails


If you look at palaeoart depicting ichthyosaurs (including six of the seven I just did... pfft!), a good chunk of it shows animals with tails which are more-or-less cylindrical, following the form of the vertebral column under the surface, skimmed with some muscle and skin, and terminating in a thunniform ('tuna-esque') caudal fin, the lower lobe of which displays a prominent ridge where the vertebrae continue beneath the fin's surface. The top lobe is generally depicted as skinnier than the bottom. But is this the most likely look for ichthyosaurs, and is it worth taking a peak at modern aquatic vertebrates to see how they're doing it?

A horribly-shrink-wrapped Ophthalmosaurus, with a stupidly-long tail. By me. Illustration: copyright © 2003 OUMNH/Gareth Monger

Caudal Fins


The caudal fins of aquatic vertebrates vary greatly in form, reflecting the locomotive styles and ecological niches of their owners. Ocean-going predators, including cetaceans, sharks, and billfish (sailfish, marlins, etc.) have evolved caudal fin shapes which allow them to reach the speeds necessary to run down swift prey and there are broad similarities brought about by convergence. The differences in the orientation of the caudal fin of fishes and reptiles, and mammals, reflect the evolutionary origins of those fins. The ancestors of aquatic reptiles presumably walked with a sprawling gait, their vertebral columns flexing from side to side, resulting in the same undulating motion in water and, therefore, a vertically oriented caudal fin. Cetaceans' terrestrial ancestors walked with an erect gait and cetaceans swim with a vertical undulation and developed a horizontally oriented caudal fin.


Predatory marine vertebrates: A. Atlantic sailfish (Istiophorus albicans); B. tiger shark (Galeocerdo cuvier); C. harbour porpoise (Phocoena phocoena); D. the Jurassic ichthyosaur, Opthalmosaurus. Image: Gareth Monger.

Streamlining Peduncles


Some of these animals also bear modified structures which improve the efficiency of their stroke. The part of the body after the anal fin (broadly speaking, the tail) is called the caudal peduncle, and contains the muscles which drive the caudal fin. It also includes the bony or cartilaginous skeleton, depending on the group to which it belongs. (In cetaceans, the peduncle is also called the tail stock.) In order to generate forward thrust, the caudal fin beats laterally in fish and reptiles, and vertically in mammals. The peduncle must also displace water during the stroke, but pushing the peduncle through water can reduce the efficiency of the caudal fin. Drag created by the peduncle during the stroke is energy wasted which could be converted to forward thrust by the caudal fin. In addition to this, water made turbulent having passed over the animal's body and fins then flows to the caudal fin. The caudal fin is less efficient in this disturbed, turbulent water than in smooth, laminar water.

Many species improve upon these inefficiencies by having peduncles which are streamlined to cut down hydrodynamic drag during the swimming stroke. For example, many sharks' peduncles are dorsoventrally-flattened to ovals when viewed in cross-section, which might be expected anyway because the muscles are grouped either side of the vertebral column – though the overlying tissues produce more-angular apexes to the oval than is achieved by the muscle mass alone.  This produces a lower profile that cuts through the water more easily during lateral beating of the tail. If the stroke generates less turbulence, the animal can transfer more of its energy to the caudal fin to be turned into forward thrust. The cross-section of the cetacean peduncle is similar, except that its oval is oriented vertically.

The peduncle and caudal fin of the harbour porpoise. The cross-section through the peduncle shows the streamlined dorsal and ventral surfaces. Image: Gareth Monger.

Caudal Keels as Laminar Flow Generators


Caudal keel as a possible laminar flow generator.
Image: Gareth Monger.
An additional feature of some fish peduncles is a 'caudal keel' situated on the outermost margins. This is sometimes formed by harder structures such as scales in animals which possess scales – a bit like ridge tiles on a roof. The keels' locations towards the distal end of the peduncle may also partially stabilise the flow of turbulent water as it passes from the animal's body and over its caudal fin. It's less efficient for the caudal fin to push against turbulent water during its stroke, but a longer caudal keel, as seen in some sharks, might convert some of the turbulence to laminar flow. This presumes that a given ichthyosaur's integument didn't sufficiently produce laminar flow on its own.

Caudal Keels as Boundary Layer Fences


The keels might also function as 'boundary layer fences', which serve to reduce slippage of water passing across the caudal fin towards the lobes of the fins. In other words, if the water flows in any other direction not associated with the forward thrust, thrust is lost and the animal must work harder. Imagine balancing a tray on one hand. If the tray is loaded with marbles and it leans slightly, it's fairly easy for all of the marbles to roll together, and the tray will tip, spilling all of the marbles at one end. If there's a small ridge at the centre, it will help to prevent each half of the tray's marbles from slipping to the other side, and it will be easier to control the tray.

Locations of caudal keels for the Atlantic sailfish (Istiophorus albicans) and the porbeagle shark (Lamna nasus). NB: The cross-section for the sailfish is an extrapolated from available photos of live animals. Image: Gareth Monger.

It's entirely possible that ichthyosaurs employed a similar system, combining a dorsoventrally-compressed peduncle and some sort of keel, to improve stroke efficiency. After two weeks of looking over literature and images online, I stumbled over a paper by Theagarten Lingham-Soliar (2016), which I wish I had a fortnight ago. Lingham-Soliar looked at convergence in lamnid sharks and Jurassic ichthyosaurs, and interpreted the soft-tissue remains in a particular ichthyosaur fossil (funnily enough, the photo later on in this article) as the impression of the animal's twisted-over peduncle. It's sometimes hard to interpret these soft tissue remains, not least because some earlier examples may have been enhanced, but if the fossil remains are suggesting chunky peduncles, it would make sense for them to find their way into artistic reconstructions.

Speculative diagram showing sections through the tail of Ophthalmosaurus. Vertebral column is shown in white, against body outline. Positions for possible keel-like structure indicated by arrows and pink dashed line. Image: Gareth Monger

So if peduncles are in, what of the ridge in the lower lobe, as defined by the distal vertebrae within the caudal fin? I can only approximate since I don't have ready access to an ichthyosaur skeleton, and I haven't yet found a detailed diagram of ichthyosaur musculature. That ridge has always been a feature of my ichthyosaur reconstructions, but those vertebrae are relatively small – they're only half the diameter of the smaller vertebrae in the peduncle, just in front of the caudal fin, forming a fairly narrow column. The majority of the caudal fin comprises soft tissue, presumably including some muscle which would be necessary to perform the adjustments to the fin's form during the stroke, i.e., preventing too much flexing which might negate the improvements brought about by the keel (re: boundary layer fence). Cetaceans do this, and their caudal fins are not especially skinny structures. It's feasible that an ichthyosaur's caudal fin vertebrae would have been bound in enough connective fibres, muscle and other tissues that they might not have been discernible in a healthy individual, and the upper lobe might not look too different to the lower.


Two highlighted caudal vertebrae, one just inside, and one just outside, the caudal fin. Note the those in the fin are approximately half the diameter of some of their nearest neighbours in the peduncle. Photo: Daderot. CC0 1.0; Digital overlays: Gareth Monger

So, considering that ichthyosaurs' forms shows them to be powerful, efficient swimmers, it's not totally unreasonable to at least consider that they might have evolved the anatomy to allow them to live as active, effective predators. And whilst the wider, flattened peduncle is likely, it doesn't automatically follow that they would have had keels as sharply defined as those found in sharks and other fish. Without knowing much about the sorts of integuments that various ichthyosaurs possessed, we can't know if specialised integument was used in a similar manner to the scutes of sailfish and their kin. I'm inclined to think scuted/scaled keels are a bit of a stretch. But a bit of definition to the peduncle might be likely.

Different ichthyosaur species were subjected to different selective pressures and, as with extant aquatic vertebrates, we should expect some variation in the external appearances of the myriad ichthyosaur species.

Lateral view of the chunky Ophthalmosaurus (based on Sander 2000), and a dorsal view extrapolated (well, fudged) from an anterior skeletal (McGowan & Motani 2003), and various pics of the great mount at Peterborough Museum. This dorsal view shows off the wider peduncle, but this still might be a tad skinny. Gotta find a decent ichthyosaur muscle reconstruction! Image: Gareth Monger.

Generalised ichthyosaurs, shown from different angles and displaying their chunky peduncles. 'Pedunkies'? Illustration: Gareth Monger).

The ophthalmosaurid ichthyosaur, Nannopterygius, reconstructed with a keeled peduncle. Illustration: Gareth Monger.


References


Bernvi, D. 2016. Ontogenetic Influences on Endothermy in the Great White Shark (Carcharodon carcharias). 10.13140/RG.2.1.2888.5367

Fish, F. E. (<-- seriously?). Biomechanical Perspective on the Origin of Cetacean Flukes. research.net

Lingham-Solia, T. 1999. Rare Soft Tissue Preservation Showing Fibrous Structures in an Ichthyosaur From the Lower Lias (Jurassic) of England. The Royal Society, 266, 2367–2373.

Lingham-Solia, T. 2016. Convergence in Thunniform Anatomy in Lamnid Sharks and Jurassic Ichthyosaurs. Integrative and Comparative Biology, Volume 56, Issue 6, 1 December 2016, Pages 1323–1336, https://doi.org/10.1093/icb/icw125

Martill, D. N. 1995. An Ichthyosaur With Preserved Soft Tissue From the Sinemurian of Southern England. Palaeontology, Vol. 38, Part 4, 1995, pp. 897–903, 1 p1.

Motani, R. 2005. Evolution of Fish-Shaped Reptiles (Reptilia: Ichthyopterygia) in their Physical Environments and Constraints. arjournals.annualreviews.org

Naish, D. 2008. Ichthyosaur Skin Impressions. http://scienceblogs.com/tetrapodzoology/

Sagong, W., Jeon W-P., Choi H. 2013. Hydrodynamic Characteristics of the Sailfish (Istiophorus platypterus) and Swordfish (Xiphias gladius) in Gliding Postures at Their Cruise Speeds. PLoS ONE 8(12): e81223. doi:10.1371/journal.pone.0081323

Veterian Key: Cetaceans. https://veteriankey.com/cetaceans/

Walters, V. 1962. Body Form and Swimming Performance in the Sogmbroid Fishes. Zoologist, 2:143-149.

Thursday, 7 July 2016

Conodonts: 520 Million Years Long in the Tooth

Decent conodont fossils are frustratingly rare. Sure, their 'teeth' are so well known they're used as index fossils, id est, the distributions of particular types are used to gauge the age of the rocks in which they're found. Lacking the hard, bony skeletons of 'vertebrates proper', they don't leave so much to fossilise; ergo, only a handful of not-teeth-fossils are known. It's hardly surprising, then, that the arrangement of the hard elements within the head isn't fully understood. The animals are generally pretty small, ranging from 10mm to 400mm, and the teeth are only rarely found associated with the animal which used them. It's not even clear from the remains themselves how they were used, with a variety of feeding methods proposed, including filtration, crushing and actively grabbing hold of small prey. It's not hard to imagine conodonts as analogous to extant eels, and eel-like lampreys and hagfish - after all, they share a broadly similar form - but the feeding methods employed by those animals are disparate to say the least.

Given the poor preservation of the soft tissue elements of conodonts, many reconstructions are understandably pretty basic represented by little more than line art (and there's nothing wrong with that). However, Davide Bonadonna has put together this incredible image, which is probably the nearest anyone is going to get to a face-to-face encounter with our fishy (fishesque? fishish?) friend. Mercilessly terrifying, mercifully small.


Rocking the 'someone stepped on my tail' look: Clydagnathus. (Copyright © Davide Bonadonna.)


So Davide's pop-eyed conodont inspired something a little less scientific from me, in the form of this Alien3-Clydagnathus mash-up, and is available on products at my Redbubble store, here. And if you prefer something a little more scientific, you can buy Jaime Headden's instead.



The conodont Clydagnathus, which, were it alive today, would gestate in your chest and eventually smash through your ribcage. Why? Because pop culture. (Copyright © 2016 Gareth Monger)


Big thanks to Davide Bonadonna for allowing the use of his work in this glorified advert. If you're unfamiliar with his incredible work, correct that immediately!

Sunday, 20 March 2016

The Rocky Transition From Paint To Pixels

Orca flies the flag


Last March, noted zoologist and living-encyclopaedia-on-tetrapods-and-selected-fish, Darren Naish, sent me some outlines to colour for Tetrapod Zoology's April Fools article. Cetacean Heresies detailed the bright colouration of extant cetaceans, and how those colours go undetected by the pitifully inadequate human eye. That black-and-white orca in your ornamental pond? Fringewhiner's Chromatic Truthometer shows it for what it really is: a gay rights poster boy. It's rainbows all the way. Rainbows are good.

Peponocephala and killer whale pod. (By Darren Naish and Gareth Monger; CC-NC-SA 2.0)

Special offers on piss-taking


The article was good fun, and was a veritable 2-for-1 deal; it parodied both a well-known fringe science blog, and one of those inexplicably popular (and subsequently internationally famous) internet memes - a photo of a blue-and-black dress which appeared to some internet users as a white-and-gold dress. In one of those bizarre twists, the woman who originally photographed the dress then came into the printshop where I work to run off a few copies of the photo, and STILL wasn't sick of talking about it.

Skamps (I think that's what we called these at uni) of generalised mosasaurs in different poses and angles. Pencil on paper. (Copyright © 2016 Gareth Monger.)


So why am I milking whales, ten months on? In short, it was the first time I'd used a digital package to put together a full-colour illustration, albeit in a rather rushed manner. At the time, nearly all of my work was coloured by hand, using gouache. (If you're not sure what that is, read my article on gouache at ArtDiscount.) If you are an experienced gouache user, you'll know it's no slower a medium to paint with than anything else, the main limitation to speed being how much detail you want to put into your image. It's considerably quicker to work with than oils, it dries reasonably quickly, and can be forgiving. However, there's a basic set-up time associated with it, namely the time taken to stretch paper, which can, if you're lucky, be as short as a couple of hours. There's nothing better than seeing a perfectly stretched sheet of 140lb Arches watercolour paper, ready to receive its first pencil mark. Conversely, there's nothing worse than seeing that your adhesive tape has failed on one side of your paper, and you've got to redo the whole damn thing. (For hints on paper stretching, see my dA post, here.)


Preliminary sketch (top) of a pair of Platecarpus, with soft tissue outline based on Lindgren et at, 2010. Revised outline (bottom) tweaked to reflect social media comments by palaeontologist Nathan Van Vranken. Note the shorter intermediate caudals' section. Pencil on paper. (Copyright © 2016 Gareth Monger.)


Material costs


This time, however, I heeded advice regarding digital illustration, and figured that these kinds of non-commercial, tight-deadline jobs would benefit from employing a more-speedy process. Material costs are also a consideration, and when a single sheet of paper costs upwards of five pounds, digital art offers a cost-effective alternative. That's not to say I've fallen out of love with toxic pigments and plant-based substrates, it's just that digital painting is very, very convenient. Also, I may go a couple of months without breaking out my paints and, inevitably, they dry out. Yes, they're water-based, but they're also awkward to rehydrate whilst in the tubes. The easiest way to get any use out of dried gouache is to slit open the metal tube and use it in the same way you would a watercolour pan. Of course, you're not really using it as gouache, but it eases the pain of seeing expensive paint dry out.

Pencil outline after some clean-up, and an initial pass through Photoshop to add some body-forming shading. Pencil on paper/digital. (Copyright © 2016 Gareth Monger.)


Going Digital, Sorta...


And so, with last year's April 1st in mind, and probably also inspired by seeing Amin something-or-other's passive-aggressive, and generally unwarranted, comments about Nic Grabow's (I think) deviatART mosasaur, I decided to knock out a quick full-colour render of a mosasaur, complete with background. Google's luck-of-the-draw-type results would determine the genus, which ended up being Platecarpus. Back in 2010, Johan Lindgren, Michael W. Caldwell, Takuya Konishi and Luis M. Chiappe published in PLOS ONE a paper on convergent evolution in aquatic tetrapods, focussing on a specimen of Platecarpus which displayed some excellent soft tissue preservation, and which suggested that a crescent-shaped caudal fin was present in life.

 Lindgren, et al (2010). CC-BY-2.5




A reconstruction in Lindgren et al (2010) (left) suggested a possible soft tissue outline for Platecarpus, based on the specimen discussed in the paper. The dorsal portion of the fluke is only tentatively restored, as implied by the fuzzy margins, but it's enough to offer a hint on how to progress with an illustration for a palaeoartist. Scott Hartman also writes about this at Skeletal Drawing, in the article 'Mosasaur Tails - Teaching the Controversy', and offers a handful of likely shapes which a palaeoartist may wish to adopt. Whatever the case, the traditional view of mosasaurs as having essentially lizard-like tails, albeit laterally compressed and ribbon-like, is out of vogue, especially for later genera, and shows that a more (superficially) traditionally-fish-like fluke was adopted by secondarily aquatic reptiles in several disparate groups. Oh, and dorsal frills are out too, having been mercilessly copied from Charles Knight's Tylosaurus for decades. Hey, I did it (over a decade ago, mind).


A pair of Platecarpus, lured into posing for this image by the promise of a David Attenborough voice-over. Digital. (Copyright © 2016 Gareth Monger.)

So here's my full-colour illustration of two Platecarpus, swimming around calmly like obedient Seaworld killer whales. The original layout was an evening's work; the colour work took a second evening. On the whole, I'm pretty pleased, and yes, of course, there are things I would change/add. Integumentary structures, for example, aren't evident, but then they might not be at this distance. The foreshortening on the caudal fin caused some confusion, with some commenting that the fluke angles were incorrect. They weren't, or, at least, they were based on the aforementioned reference, and it was the foreshortening causing them to appear unfamiliar. But that's to be expected when most pictorial reference is in diagrammatic, lateral view. One noted mosasaur expert didn't like the blubbery look; another palaeontologist figured it simply denoted healthy individuals. There was a speculative angle to this, which was to show a more fluid outline in an animal which spends its entire life in fluid.

But on the whole, not so bad for a couple of evenings' work.

References:

Hartman, S (2016) Mosasaur Tails - "Teaching the Controversy" www.skeletaldrawing.com/home/mosasaurs-teaching-the-controversy

Lindgren J, Caldwell MW, Konishi T, Chiappe LM (2010) Convergent Evolution in Aquatic Tetrapods: Insights from an Exceptional Fossil Mosasaur. PLoS ONE 5(8): e11998. doi:10.1371/journal.pone.0011998

Naish, D (2015) Cetacean Heresies: How The Chromatic Truthometer Busts The Monochromatic Paradigm. http://blogs.scientificamerican.com/tetrapod-zoology/cetacean-heresies-how-the-chromatic-truthometer-busts-the-monochromatic-paradigm/


Want to support me?


If you like what you're reading and you want to help me keep this going, maybe take a look at my Redbubble page? Here's a mostly-relevant mosasaur (Globidens, not Platecarpus, but who cares?):


Globidens, Haida-style, available on t-shirts, mugs, and a butt-load of other stuff, via Redbubble.

Sunday, 29 November 2015

Stuck For A Palaeo Gift? Decision-Making Just Got Easier...

Picky Palaeo People


This is shameless self-promotion whereby I suggest you buy my art on t-shirts, mugs, hoodies, and whatever else Redbubble keeps in stock, and as such, I'll not be spamming the Facebook groups (just the Twitter hashtags). If you're one of those people who is lucky enough to count a palaeontologist amongst the inhabitants of your Christmas gift list, then you could do far worse (I think!) than take a look at my Redbubble gallery and peruse the palaeo-themed graphics and doodles which populate its pages.

An ichthyosaur, plesiosaur and pterosaur, in the style of Pacific Northwest Amerindians, plus Yi qi in the style of the crows from Disney's Dumbo. (Copyright © Gareth Monger.)


Is there an ichthyosaur nerd in your life? Sorted! Do you know of a plesiosaur fancier out there who's still wearing the shoddy transfer t-shirt they made at college in 1990? Upgrade them! Are you sick to death of hearing your neighbours argue because one of them is perpetually frustrated by the lack of Yi qi apparel in the palaeoverse? This might be the fly-remover for their ointment!

(L-R) The Palaeoplushies Queen, Rebecca Groom, wearing the Haida ichthyosaur; 'How Train Your Velociraptor'; a road sign we'd all like to see more of; 'tyrant teen', Tristan Stock, looking buff whilst wearing 'The Membraned Crusader'. 


So pop along to the 'GaffaMondo' gallery at Redbubble and take a peek. There you will find a good chunk of the supporting graphics, doodles and cartoons which I generated over the last twelve months, which is, coincidently, Pteroformer's first year online. With luck, I'll be able to add to this collection over the next twelve months, perhaps producing images to commemorate further new discoveries, as I did for Yi qi. Needless to say, Pteroformer isn't a commercial site (in the sense that I'm not paid to write it) so any money made on the back of it is very gratefully received - plus it means I can keep it ad-free. And don't forget, you'll be supporting original palaeoart, which means that you're joining the good fight against shitty broken-wristed raptors clad in ill-fitting snakeskin pyjamas. Not so good if you have a feather allergy, but it's a small price to pay to get away from 1990s shrink-wrap hell.

Support Original Palaeoart


You'll notice the Support Original Palaeoart graphic - it doesn't mean I'm endorsed, just that I'm one of many supporting the movement, spearheaded by Mark Witton, John Conway and Darren Naish. You can read all about it over at Mark's blog, here.

Late Announcement!


David Orr has just published an article at Love In The Time Of Chasmosaurs, giving a brief run-down of some of the palaeontology-themed artwork, books and other bits you can buy, including work by Ricardo Delgado, Fred Wierum, Levi Hastings, Jon Davies, Juan Carlos Alonso, Matt Martyniuk, Brynn Metheney and Angela Connor. Happily, I got a mention too - as did David's, and his wife Jennie's, great early learner's book, Mammoth Is Mopey. I've got a copy; one day I might let my kids look at it.

Next up: Celebrating 20,000 page views with pterosaur papercraft!

Thursday, 19 November 2015

Skimming Rhamphorhynchus (or Rynchops For The Win)

Tropy Palaeo-Cliché


There are plenty of palaeoart examples of Rhamphorhynchus skim-feeding in the style of the extant tern-like bird, Rynchops. It's understandable - after all, Rhamphorhynchus is a seagoing pterosaur with a mouthful of forward-pointing teeth, occasionally preserved with the remains of its fishy meals within it. Factor that stuff together, and it's easy to imagine Rhamphorhynchus zipping along just above the surface of some shallow Jurassic sea, thrusting forward with its mandible slicing the water's surface, and snatching morsels of food as it finds them.

Humphries and Chums' 'Just Say No!' Campaign


In a 2007 paper investigating the possibilities of pterosaurs engaging in skim-feeding, Humphries et al found few adaptations towards this method of prey-capture, with the skull lacking the types of reinforcement seen in Rynchops. Read the paper here. Despite the refutation of the idea, it's a persistent one in palaeoart, probably in part because it makes for attractive images. Thanks to Humphries et al, this is probably as close as I dare get to showing a rhamph skimming:

Rhamphorhynchus experiments with skim-feeding, remembers why it doesn't. (Copyright © 2015 Gareth Monger)

Anyway, none of that is what you'd call new news - I just wanted to draw a cartoon of a pterosaur.

References:

Humphries S, Bonser RHC, Witton MP, Martill DM (2007) Did Pterosaurs Feed by Skimming? Physical Modelling and Anatomical Evaluation of an Unusual Feeding Method. PLoS Biol 5(8): e204. doi:10.1371/journal.pbio.0050204

Friday, 26 June 2015

Hallucigenia Gets (Slightly) New Make-Over, Still Weird

Weirdo Cambrian multi-tuby worm thingy, Hallucigenia, has had an overhaul, thanks to Martin R. Smith and Jean-Bernard Caron (read it here). You can now confidently draw it with eyes and a cake-hole now that Smith and Caron have determined which is the front. It's a big deal for Cambrian workers and demonstrates how much work sometimes has to go into reconstructing these ancient invertebrates. Bear in mind that many of the Cambrian's organisms are known from scrappy or disassociated remains, or good(ish) remains of animals which are so different from any extant creatures that they appear to defy logic. Anyway, it's cool and you should all buy this t-shirt.

Hallucigenia (reduced, as is the law for cartoons). And it's on a t-shirt! (Copyright © 2015 Gareth Monger.)

Wednesday, 24 June 2015

National Geographic's Antidote To Terminal Monster Saturation

The palaeontology community's members are all in therapy, thanks to Jurassic World's insistence on filling a(n ENORMOUS) fictional theme park with some of the worst reconstructions of Mesozoic reptiles known to man. The TetZoo guys didn't even make it to the end of their own review*, with Darren Naish weeping uncontrollably after only fifteen minutes, and transmission being cut seconds after what can only be described as a muffled thud. Listeners were left to make up their own minds as to what had transpired, with many speculating that they'd just heard Naish's mercy killing at the hands of John Conway. The Love In The Time Of Chasmosaurs blog clearly comprises a masochistic crew, who offered up not one but two reviews on JW. (And they just added a third about an hour ago.)

The point is, you don't have to look too far to find a palaeo community review for this year's main Summer blockbuster. Jurassic World has attracted much attention since people began speculating as to how they might depict some of the film's key creatures. It's nearly two decades since John Hammond demonstrated how you should NEVER EVER run a zoo and, in that time, dinosaur reconstruction has evolved at an unimaginable rate. Would Jurassic World reflect this? Would we get feathered 'raptors'? Would they possess the correct wrists described by Dr Alan Grant RIGHT AT THE BEGINNING OF THE FIRST MOVIE? And, most importantly, would their T. rex still move around the park, one earthquake-causing footstep at a time, taken every thirty seconds? ("T. rex doesn't want to be fed, it wants to hunt!" Not gonna happen. Not when everything within a couple of miles knows you're coming.)

Chris Pratt's character taunts Jurassic World's Velociraptors by demonstrating the range of motion they should be able to achieve with their arms. (Copyright © 2015 Universal Pictures.)
By now you already know the answers. You've either seen the film or read the reviews, so in the interest of avoiding repetition, I'll spare you a long and damning run-through of how bad they got it. Jurassic World was, for me, an enjoyable monster romp - a worthy sequel to Jurassic Park. I got giddy sat at home, waiting to leave for the cinema. I got chills hearing the music. And I nearly wet myself during the tag-team end battle. But it's not a film about dinosaurs. It is, however, a love letter to the first film, as demonstrated by numerous references and nods to Jurassic Park. It also flicks the Vs at the less-well-loved Jurassic Park III, if only by having the first film's T. rex smash through a mounted Spinosaurus skeleton during the final reel. And remember how the JP3 promo art made use of a triple claw-gash to form the III? The only reason I could see for Improbable Indominus rex having four manual digits was so that Universal could use the same trick for this fourth instalment. Pfft.  Yes, it's daft, overblown, and it makes scientists cry. But it's fun and noisy and holds children's attention for the duration.

These are the take-home points of the Jurassic Park series:
  • Revived Mesozoic animals will, upon their release, always, ALWAYS go bat-shit crazy and attack every human in sight, irrespective of their general temperament when confined, or whether they're piscivorous, carnivorous or veggie-saurus, Lex, veggie-saurus!
  • Large theropods will announce their approach with impact-tremor footsteps. They will then stand and roar, I guess because they're sporting types, and think it fair to offer their intended prey a chance of escape.
  • A hunting dinosaur has no concern for its own wellbeing. It will happily smash through buildings, walls, perimeter fences and steel doors in order to catch prey. It will go to any and all lengths to catch a person, inconvenience be damned. It has no concept of 'too much effort'. (Extinction hypothesis?)
  • Indominus rex was originally engineered as a means to retrieve broken-down gyrospheres, hence its enormous gape. Probably.
  • Jurassic Park films would all end after only ten minutes if ANYBODY had conducted a decent risk assessment analysis. Ergo, in the JP universe, people are really, really stupid.
So will the Summer of 2015 go down in history as the moment when film & television decided that palaeontology  sexy? Not quite.

Before they took a blood shower: Dr. Luke Gamble at front and, left to right, Matthew T. Mossbrucker, Dr. Steve Brusatte and Dr. Tori Herridge. (Copyright © 1996-2015 National Geographic Channel.)
Thank the flips for National Geographic's 'T. rex Autopsy'. If you've not seen it, the premise is a straight-forward one: make a fully-furnished Tyrannosaurus rex corpse, hire a team of palaeontologists and vets, and set them to work dissecting it. Obviously turning that into a reality was anything but simple, as palaeontologist and adviser-to-the-show Dave Hone explains (here). And they do a brilliant job. The dissection team does not behave as if its members are crawling over a special effect. They do their level best to convince the viewers - and themselves - that the animal is real. For the most part they pull it off, too. Excepting the odd, faked, reflexive cough at smells we know aren't there, their reactions at having been presented with a 'real' non-avian dinosaur are a joy to watch. My seventeen-year-old daughter arrived home partway through the programme; gawping confusedly at the television screen, she enquired as to where on earth the makers got hold of a fully-fleshed dinosaur. That's how good it is. Of course, if you're looking for the tells which betray the animal's synthetic construction, they're there, well hidden. But who cares? Disbelief is easily - and wilfully - suspended.  Hats are tipped at those who conceived, designed, and executed this remarkable piece of television. It more than makes up for those well-documented missed opportunities of Jurassic World.

A few weeks ago LITC announced the Jurassic World challenge. In order to try to increase awareness of real palaentology, and perhaps direct some funds back towards it, LITC suggested that if you go to see the film you could spend at least the equivalent amount on something which will benefit palaeontologists, research institutions, palaeoartists and museums. You could buy a book, or a piece of palaeoart, or donate to a museum or crowd-fund someone. There's loads to choose from if you look around.

Since I have bills like everyone else, it would help me enormously if people bought a t-shirt from my Redbubble page. You can show off your pop-culture-savviness with a hyper-daft Guardians-Jurassic-World-How-To-Train-Your-Dragon mash-up, or keep reminding everyone that T. rex Autopsy was the best thing on telly since sliced tyrannosaur.

Juraasic World and T. rex Autopsy fan art t-shirts, available at my Redbubble page, here.

It's good to get that JW stuff off my chest. Normal service will resume soon. There's a stack of stuff sat there in draft, including more wandering sauropod ecosystems, more Yi qi, and more pterosaur quad-launching. Laters!

*Of course TetZoo did the whole interview. Listen to it - its very entertaining.

Thursday, 28 May 2015

Quadrupedal Launching In Bats And Pterosaurs

I can't recall when I first heard about 'quad-launching' as a serious suggestion for pterosaurs getting airborne, (I was under a rock, palaeontologically-speaking, between '06 and '12) though Mark Witton's excellent 'Pterosaurs - Natural History, Evolution, Anatomy' was the first time I remember anyone going to any effort to depict it pictorially. Indeed, all of his book's pterosaurs are shown mid-launch for their profile images, as if Mark is making a concerted effort to familiarise readers with the concept. Most of the other books on my shelves tend to hedge their bets, offering up a selection of methods, including (but not limited to) dropping from elevated perches, facing into the wind and spreading their wings, and taking a run up whilst flapping.

My biggest problem with quad-launching was that I found it hard to visualise. I've never seen anything get airborne like that. Given that birds are obligate bipeds and their legs are not connected to their wings by a continuous flight surface, they are free to either jump into the air, as with pigeons, or propel the animal along the ground with an energetic run-up, like swans and geese. Many palaeontologists agree that pterosaurs were obligate quadrupeds and that their fore-limbs and hind-limbs were, in life, connected by the wing membrane. Birds are, therefore, a poor analogue for launching pterosaurs, and it is for these, and other anatomical reasons, that palaeontologists believe that pterosaurs' primary launch method probably involved a highly-energetic 'push up'.

A recent post at Pterosaur Heresies again demonstrates its author's frustrations with the problems he sees with the forelimb launch mechanism. The article points out that vampire bats achieve a considerable height from an initial leap before they perform a single flap, and that pterosaurs would be unlikely to achieve such a feat. In a bid to attempt to understand bats taking off from the ground (only a few species can do this) I looked at video footage of a fringed myotis taking off. Adams et al, in their 2012 paper, looked at how bats use their uropatagium to facilitate launch, and made available the following video:


There are four video links in the online paper, showing launches from various angles. In order to get a better idea of what's going on, I rendered the bat as a very-basic stick figure, traced from screenshots of the first online video. The wings' tracings show the stroke, and the head shows the positions of the animal relative to the ground.

Sequence showing a bat (Myotis thysanodes) taking off from the ground, mapped from screen-shots of film footage. This section of the sequence totals around two-and-a-half seconds. (Sequence drawn by author, traced from footage available with Admas, Snode & Shaw 2012.)
In the next image, the seven stages are overlaid in order to get a slightly clearer view - though I think both diagrams are useful when taken in together. The bat accelerates quickly, with its wings in contact with the ground in stage 1-3 (in 1 and 2, they are still flush to the floor). In stage 4 it begins the upstroke, is preparing for its first proper downstroke at 5, and has achieved that downstroke by stage 7. It's already flying and is only a few inches off the ground. My understanding, at least for M. thysanodes, is that when it jumps its inertia carries it a little higher than it would appear when standing with its arms stretched out beneath it, but it's enough to get the first flap in, and by then it's already airborne.

The same bat's take-off sequence, overlaid in order to better show the small area required for a successful launch. Black numbers denote head positions during launch; red numbers denote left wingtip positions. (Sequence drawn by author, traced from footage available with Admas, Snode & Shaw 2012.)
About a year ago I began work on a graphic novel showing the birth, life and death of Nyctosaurus. I may have underestimated how long this would take to put together, so it's still filed under 'ongoing'. But in order to understand quad-launching, I put together a couple of graphics showing an adult Nyctosaurus getting airborne, both of which inspired the bat graphics:

Overlaid launch sequence for a male Nyctosaurus gracilis. (Copyright © 2014 Gareth Monger)
And the looong version:

Launch sequence for Nyctosaurus. Nicked from my deviantART profile, hence the whole lo-res thing. Copyright © 2014 Gareth Monger)
So there you go. Now that I've done the bat thing, I might refine the Nyctosaurus graphics. I might even put together a cel animation at some point. There's nothing overly scientific in all that, however it might prove useful for those of you out there who are into your leather-flappers and pterosaurs.


References:

Adams RA, Snode ER, Shaw JB (2012) Flapping Tail Membrane in Bats Produces Potentially Important Thrust during Horizontal Takeoffs and Very Slow Flight. PLoS ONE 7(2): e32074. doi:10.1371/journal.pone.0032074

Elgin, R.A., Hone, D.W.E., and Frey, E. 2011. The extent of the pterosaur flight membrane. Acta Palaeontologica Polonica 56 (1): 99–111.

Friday, 22 May 2015

Standing Tall: Stegosaurus

This blog was never conceived with the intention of filling it with speculative palaeoart, but it's as good a place as any to put it. Stegosaurus has had a fair bit of coverage in recent months, with the NHM's mount being used to estimate the animal's mass, and Saitta 2015 looking at apparent differences in individuals' plates to determine the animals' genders. Padian and Carpenter disagreed, and Theropoda looked at the health implications of stegosaurs dragging their tails (such as constipation).

Superb illustrations by John Conway and Mark Witton got me thinking about those plates. Palaeontologists have put forward various ideas regarding their purpose, the most popular of which being thermoregulatory aids, display structures and defensive structures. In nature, structures often have multiple functions, with secondary functions being unrelated to their primary function. Feathers, for example, probably developed initially for insulation, but could have been easly modified for use in display, either through behavioral means or by changes in pigmentation. Structural modification of the feather - and other key anatomical features - then endowed the owner with an aerodynamic advantage.

That's a long-winded way of suggesting that Stegosaurus's plates probably did not perform one single function. Some of that's already been touched on in this earlier post, but I'm keen on the idea that part of Stegosaurus's display is concerned with how tall an individual looks, i.e., how much vertical space it occupies, especially in the eyes of potential mates, conspecific rivals and would-be predators. With fuzziness now known to be present in (some) ornithischians, I'm happy to speculate that some stegosaurs may have used stiff fur or 'fuzz' as it's often called, to extend the margins of the dorsal plates. Many palaeoartists, palaeoillustrators and palaeontographers already restore those dorsal plates with a sizable soft-tissue (see comments) keratinous extension. An additional growth of stiff hairs as a light-weight projection could, in theory, increase the size of the plates' appearance. Compared to a bone-and-flesh plate, the hair component would be less demanding on the animal, given that once the hair as at the surface, it's a dead structure, and no longer requires a blood supply in order to maintain it.  Of course, if it's concerned with sexual display, it may be renewed seasonally, and shed after mating. This would get around the problem of it getting trashed through day-to-day activities, and filling up with dirt, mould and parasites - which nobody wants.
Stegosaurus stenops, displaying some serious fuzz. Not unlike a filthy old coconut husk. (Copyright © 2015 Gareth Monger)
Anyway, it's just a thought. And this post is supposed to be short and sweet, like the Holocene.

Next up: Yi qi (again).