Fall down mountains, just don't fall on me
For most men, bless us, everything is about size and quantity. Car engines, televisions, stereo wattage, houses (and associated drive space), computers, various dangly appendages... they’re all the same. If they’re bigger, more expensive or exist in greater quantity, they’re far better than their diminutive alternative. Being the simple, simple things that we are, men posture and flaunt their various oversize appendages to demonstrate their dominance over subservient men and impress the ladies. Perhaps the only exception to this is the gee-whizz world of gadgets and technology: mobile phones, MP3 players and that kind of thing. Here, smaller is better, right to the point where you can’t dial a phone number even with your pinkie finger without smooshing the entire dialling pad or loose your iPod through the seams of your trouser pocket. But hey, who cares: it’s smaller than the brick of a phone owned by Derek, who could only loose his should it fall into a rice sieve. Go figure.
We’re quite open-minded in the world of palaeontology, however, and we flaunt both ends of the size spectrum to harvest all the moneys, honeys and, er, bunnies that fill the life of a typical palaeontologist. Still, for all the neatness of tiny little fossils, nothing grabs headlines more than ‘biggest ever discovered’. Unsurprisingly, pterosaur researchers are just the same and willing to big-up any large flying reptiles they may find. I’ve spent much of the last few weeks piecing together the history of this (quite literal, in one view) bigging-up of pterosaurs, documenting the discovery of the largest pterosaurs known from 1871 until today (to clarify the specificity of that date, Dave Martill, my PhD supervisor, has the slightly more involved job of piecing together the pterosaur record-breakers from 1784 until 1870). For once, this was not research conducted as part of a futile effort to finish my PhD, but instead for a presentation: the results of this bit of historical research are to be published, in poster form, at the Dinosaurs - A Historical Perpsective meeting being held in London next week (for those living in the future, next week is the 12 – 16 of May, 2008). Unfortunately, due to desperate finances, I won’t be attending the meeting in full, but will be around to collect people’s coats on their way in on the Tuesday morning.
So, what’s the story with these giant pterosaurs, then? Well, prior to the 1870s, the biggest pterosaurs were not that magnificent, perhaps only 4 m or so across the wings, and therefore not much bigger than the largest modern birds. What’s more, they were only known from the most diminutive of fragments from deposits like the Cambridge Greensand of England, where the pterosaur fossils look like they’ve been chewed up and spat out by a rhinoceros with acidic saliva. Complete pterosaurs were known, of course, but only comparatively small critters like Pterodactylus and Rhamphorhynchus from German deposits that still, to this date, have yet to yield a real pterosaur giant. Hence, it appears that Europe was not the best place to look for giant pterosaurs. Unsurprisingly, it was the USA, land of Supersized fast-food, Supersized cars and Supersize waistlines, that provided the worlds’ first truly enormous pterosaur. Its discoverer was one Othniel Marsh, the palaeontologist famous for his rivalry with Edward Cope. Funnily enough, Marsh championed his discoveries American pterosaurs as the first of their kind, but Cope may have beat him to it by several years (a story for another night, perhaps). Marsh and his expedition found the first remains of these giants in the Niobrara Chalk of Kansas, a deposit laid down in the continental seaway that bisected North America in the Late Cretaceous. Marsh’s initial discoveries (1871, chronology fans) were fragmentary, but one bone – a bit of wing metacarpal (metacarpals, for those who don’t know, are the long bones that connect your fingers to your wrist: each pterosaur forelimb has one particularly large metacarpal to articulate with their massive wing fingers) – hinted at a form with a 6.1 m (20 ft wingspan). This is pretty damn big, being almost 50 per cent longer than a large family car. The next year saw Marsh’s teams find a complete wing that confirmed Marsh’s wingspan estimate and, more astonishingly, reveal even bigger pterosaurs with 6.7 m wingspans. But what were these winged leviathans? Marsh initially dumped these remains in the genus Pterodactylus in 1872, noting their similarity to this European animal including the shape of their teeth. Marsh had this a little around his neck, however: in 1876, Marsh described newly-discovered skull material of these forms that revealed they had no teeth at all. Like, anywhere. They were, as we say, edentulous. Presumably, Marsh was describing fish, bird or marine reptile teeth associated with the pterosaur remains, because, even in the 140 years since Marsh’s work on Niobrara pterosaurs, there’s not one tooth known from any Niobrara pterosaur. Anywho, the lack of teeth in the Niobrara remains gave Marsh enough taxonomic clout to name a new genus, Pteranodon in 1876, and new remains described in the same year gave Marsh his largest ever Pteranodon wingspan estimate, 7.6 m. It was suggested in 1966 that even larger, 10 m span Pteranodon once existed, but Marsh’s estimates are probably more accurate. We’ve now got something like 1100 specimens of this critter, Pteranodon is, without a shadow of doubt, the best known of all giant pterosaurs.
Thing is, while Pteranodon is the best known giant pterosaur and had a wingspan certainly not worth sneezing at, it was most certainly not the biggest pterosaur. The first hints of even larger animals were found but not recognised by C. A. Arambourg in the late 1930s or early 1940s: this Jordanian material, thought by Arambourg to be a wing metacarpal, gave a wingspan of 7 m and was named Titanopteryx in 1959. Arambourg’s pterosaur was not really understood properly until the 1970s, when Douglas Lawson found a truly gigantic pterosaur remains in Late Cretaceous deposits of Texas. Several kilometres away, a bunch of smaller, but considerably more complete pterosaurs were found that bore remarkable similarity to what Times Magazine dubbed ‘Lawson’s Monster’. Lawson named them all Quetzalcoatlus in 1975 and estimated that the wingspan of the biggest was anywhere between 11 and 20 m: at very least, that’s 30 per cent larger than the biggest Pteranodon. Quetzalcoatlus then fell into the hands of Wann Langston Jr., who favoured the lower wingspan estimate In 1981 based on comparisons with the relatively small (6 m span) Quetzalcoatlus and biomechanical issues acting on 20 m span pterosaur wings.
Now, Quetzalcoatlus proved a key role in unlocking the secrets of Arambourg’s Titanopteryx. The smaller Quetzalcoatlus skeletons revealed that this taxon had an enormously elongate neck comprised of relatively few vertebrae, and the longest of the neck bones was a dead-ringer for the Titanopteryx ‘wing metacarpal’. Lawson realised this in 1975 and, with the 1984 discovery of another pterosaur with an absurdly proportioned neck in Uzbekistan (not a giant, mind), it dawned on pterosaurologists that a whole bunch of these fellows once existed. L. Nessov appropriately named this group Azhdarchinae in the same year, basing the name on the Uzbek word for ‘dragon’ (we’ve now raised the taxonomic rank of these guys to Azhdarchidae, by the way. That’s yet another story, however). Because it soon became apparent that the name Titanopteryx had already been applied to a tiny, tiny fly, Nessov, along with A. Jarkov renamed Titanopteryx as Arambourgiania in 1989, and seven years later, Eberhard ‘Dino’ Frey and my PhD supervisor re-described the vertebra and the size of the animal it represented. With refreshingly frank admittance of their inability to resist the urge to scale-up Arambourgiania despite having next-to-no-remains, Frey and Martill estimated a whopping 11-13 m wingspan for this animal, possibly dwarfing Quetzalcoatlus by 2 m.
Even bigger azhdarchids were to come, however. In 2002, E. Buffetaut and friends revealed yet-another poorly-known but clearly gigantic azhdarchid to the world: Hatzegopteryx. This animal, from Late Cretaceous deposits of Transylvania, is only represented by scrappy skull and limb material, but is thought to have spanned at least 12 m and, by my estimation, stands about 3 m tall at the shoulder. Thing is, while the remains of Quetzalcoatlus and Arambourgiania hint at relatively slender, lithe creatures, Hatzegopteryx is built like the proverbial fired-clay outbuilding. What little is known of its jaw is massively constructed and indicates a skull width of at least 50 cm. That’s half a metre. I’m barely 50 cm across my shoulders: Hatzegopteryx could probably swallow me, a fully grown, 23-year old man, whole. If we scaled this up to the skull proportions of the small Quetzalcoatlus, we’d have a skull 5 m long. Now, because skulls of this size are typically reserved for monstrous marine reptiles or filter-feeding whales, it’s thought that these estimates may be a bit wrong. However, even more conservative estimates of 2.5 m give Hatzegopteryx one of the longest skulls of any land-based animal, and certainly the largest of any flier. It also bears thought that the record holders for the longest skulls of land animals, the elaborately frilled horned-dinosaurs, are cheating to get their place in the record books by having much of their skull length occupied by accessory frill. The length of the Hatzegopteryx skull is almost entirely jaw, however, making it more comparable with the long-jawed skulls of big predatory dinosaurs like Giganotosaurus and Spinosaurus. Seeing as the latter has a skull of around 1.8 m length, it appears that a twiglet-boned, lanky pterosaur had longer jaws than any dinosaur. Who’d have thought it?
Alas, the rest of Hatzegopteryx is virtually unknown. We have the occipital region (the part of the skull that connects with the neck), which is deeply-sculpted for anchoring powerful neck-elevating ligaments and muscles. The humerus is poorly preserved but comparatively more robust than that of the giant Quetzalcoatlus. That’s about it, but the bottom line is clear: Hatzegopteryx was absolutely enormous and it remains the largest pterosaur we know of. In fact, I have it on good authority that, based on our current understanding of pterosaur biomechanics, the pterosaur skeleton would have to be dramatically altered to facilitate much larger forms. Despite this, there were rumblings in 2005, however, of an even larger pterosaur being found. Y’know: something in the 20-25 m range. Unfortunately, this beastie was mentioned to the public well before it should’ve been: the alleged remains of this creature have since proven to be non-pterosaurian and several pterosaurologists (some of whom I know quite well – but no names mentioned) retire sheepishly at its mere mention. For the less squeamish, Cameron McCormick has crafted a diagram and blog post discussing this most monstrously unreal pterosaur.
So, there you have it: highlights of the history of giant pterosaurs in 1,780 words. There’s a whole lot more to go with this stuff: giant Jurassic pterosaurs, giant pterosaurs in the Lower Cretaceous, giant pterosaur footprints, giant palaeontologists vs. giant aeronautical engineers on the mechanical constraints facing a giant pterosaur… if only there was a giant amount of time to tell it all (dy’see what I did there?). For the moment, you’ll have to be content with the image accompanying these words: it depicts the 1.75 m tall author, somewhat shaggier than his last comparison with a giant pterosaur, being dwarfed by the mighty Pteranodon (on the right) and the monumentally-sized Hatzegopteryx on the left. Note that Pteranodon, for all this talk of being much smaller than the largest azhdarchids, is no midget itself. No giraffe this time – it was eaten by Hatzegopteryx. Oh, that reminds me: big things - big, Earthshaking, city-levelling things - are about to happen in the world of azhdarchid palaeobiology. What’s that, you ask? Well, that would be telling. Come back soon, dear friends, and all will be revealed…
  
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Uploaded on May 4, 2008
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Monster Love
And, while we’re here…
Happy second birthday to Mark’s stupendous Flickr site
Yes folks: two years old today*. Clichéd as it may sound, it really doesn’t seem like two years since I started posting photographs and pictures on here. Back then, I was a fresh faced first-year PhD student looking out at the ocean of time that a three-year PhD project seemed to promise: now, somewhat more grizzled and scarred, most of my PhD time lies over my shoulder and I’m staring down the barrel of final submission. Scary stuff, I assure you.
*My site is not alone in celebrating an anniversary today, however, with the excellent Ask a Biologist website hitting its first full year of service this very moon. For those of you unfamiliar with the site, it’s essentially a big public forum in which you can ask respectable scientists any questions you have about biology. Personally, I think it’s an excellent idea for making science accessible and demonstrating that researchers do not inhabit ivory towers: well, not all scientists, anyway. The site caters for people of all knowledge levels and biological disciplines, so you can find answers to everything from detailed mammalian taxonomy to just how you could catch a tyrannosaur should they still be alive and you were mad enough to try. And, of course, if someone hasn’t asked a question already, you can ask it yourself (hence the name). Go on: take a quick peak there now – just promise to come back, y’hear?
Still, if the next Flickr year works out like this one, I can’t complain too much. This year saw my first real forays into the murky world of academia: wanting to get my palaeontological career off to its finest start, I gave my first conference presentation and told the world’s pterosaur researchers that everything they thought they knew about pterosaur mass may be wrong. Still, it went down pretty well for a talk that I feared might end up in my hospitalisation and, with a bit of luck, the paper will be out before the end of the year. Speaking of which, 2007 also heralded my first technical publication with the pterosaurs-really-cannot-skim project seeing the light of day and the accompanying press-release image circulated very widely across the ‘Net. Since then, I’ve been working lots with my research group to produce several other projects – some quite bizarre - which are currently floating around our office in various states of completion. Perhaps most exciting of all, however, is that my first ever solo paper was recently accepted for publication in the journal Palaeontology and should be out around the end of this year (or very early next). Good times, then, and it would be unfair to me not to acknowledge all those people, both new friends and old, who’ve been so supportive over the last year.
Of course, while all this has been going on a few pictures have made it onto the web. Pterosaurs have, once again, been the principle focus but a few other critters, namely oversize panzerbirds and scary horned dinosaurs have snuck in, too. Thanks in part to this site, some of the pterosaur pictures have made it into books, including my image of the newly christened Tupandactylus and the Tyrannosaurus consuming azhdarchids. There’ve been a few forays into the world of literature with the atypically popular image of a killer weed, a return-trip to Maple White Land and an effort to unmask the Opera Ghost. More recently, a bridge between written word and the silver screen was made with a depiction of everyone’s favourite secret agent, albeit one that’s about as far from his shiny cinema portrayal as you can get. Sadly, I’ve not been as productive as I was in my first year: a tighter constriction on my free time has been a factor in this, as has the fact that some of my nicer, newer palaeoart images have been reserved for other projects and you’re not allowed to see them - yet. However, another significant and wholly surprising reason stems from a newfound passion for, you know, whatchacallit, art. Big canvases, crayons, pastels, abstract symbolism - all that sort of thing. You folks were witness to the start of it all - a rather bizarre graphic brain dump that led to two other abnormal images (here and here - and have seen one other picture somewhat more representative of more recent work (along with pictures by my long-suffering housemates), but the vast majority of my arting remains undocumented. This is a conscious decision on my part, actually: tempting though it is to put this stuff on Flickr to see what people make of it, most of the images are quite personal and self-reflective, drawn for me rather than for other people (if you see what I mean).
And that brings us rather neatly to this new image. As with last year, I wanted to draw something that tied together all the loose strands of my Flickr output for the last year. After a whole lot of head scratching, it dawned on me that a homage to one of my favourite films, King Kong, was somehow perfect. Pterosaurs? Check. A reference to some kind of literary (erm, sort of) work? You betcha. Ample opportunity for an overly long, pretentious essay? Most definitely. It also loosely ties in with all the retrospection above: having recently found a bunch of my old sketchbooks from around 15-16 years ago (cripes, I’m getting old), I rediscovered a plethora of King Kong based sketches that I drew when I was eight or nine, at the height of my juvenile Kongmania. Perhaps unsurprisingly, this recent effort is has a wholly different attitude to the city-smashing gorilla-induced mayhem that I depicted all those years ago, but drawing an oversize ape again still smelt of sweet nostalgia. Mmm.
As a trainee palaeontologist, I don’t think I’m alone in my affection for King Kong, or at least the film genre that it helped define. Other palaeontologists have well-documented affection for the likes of Godzilla (check out this for the worryingly developed pseudo-science of this particular giant reptile), Valley of Gwangi, One Million Years B.C. or the film that really started the whole run-away-from-the-giant-monster genre off, the 1925 silent movie of The Lost World. In fact, King Kong was original envisioned as a talkie-remake of this film, but the story soon took its own direction. In all cases, there is something immensely glorious for a palaeontologist to see his favourite fossil critters brought to life and terrifying people. I guess a lot of this stems from seeing creatures only otherwise represented by dusty old fossils in a far more dynamic light. Granted, many of our favourite monsters are not animals that have any basis in reality (like your Kong’s, Godzilla’s and Beasts from 20,000 Fathoms), but they are close enough to the real McCoy to be enthralling. King Kong is undeniably the best of the bunch, however: not only does it feature a giant representative of the most charismatic ape species going, but it also has a Tyrannosaurus, Pteranodon, Brontosaurus, Stegosaurus and several other beasties. Of course, having a line up of A-list fossil species does not necessarily make a good film, but it certainly helps.
Thing is, these critters were not actually in original King Kong cast. When first conceived by Merian Cooper and Ernest Schoedsack, the film was going to be made with live animals rather than Willis O’Brien’s excellent stop motion. Although made on a tight budget by the flagging RKO Studios, King Kong’s 1933 release was tremendously successful and the film was re-released in the 60s, albeit with some of the nastier bits removed (such as native islanders being squashed into the mud by a huge gorilla foot). This was not the first time the film received editing for content: a scene in which several hapless sailors are attacked by giant crabs and insects was cut following it horrifying a preview screen audience, and the original film also featured a brief appearance by a Styracosaurus that ended up on the cutting-room floor. Although these scenes have now been lost, Peter Jackson recently re-made them to feature in an extended DVD version of the original movie. Sadly, thanks to the people who make DVD's being unjustifiably nasty, you can’t get this version over here in the UK. Anywho, thanks to its success, King Kong went on to spawn an official sequel and numerous spin-offs. The Japanese Godzilla production team, Toho, got hold of the King Kong licence in the 1960s and made loads of rather silly films featuring an even bigger version of Kong doing daft things like scrapping with Godzilla. Even worse was the 1970s remake with the Kong effects produced by a very obvious man in a gorilla suit. Then, of course, in 2005 we saw an epic remake of the original by Peter Jackson, which turned out to be rather good (well, I thought it was, anyway).
Of course, with so much history behind this franchise we could talk for hours about the production of the films without touching on their subject matter. However, seeing as the reason I like the whole King Kong thing so much is its subject matter, it’s time we move onto that. King Kong’s story gets everything right for a monster film narrative: it’s a streamlined, simple plot with as little complication as possible. There’s no explanation for the survival of extinct animals into ancient times, no logistical details of just how you load an unconscious, giant ape onto a raft to float him to your boat. No, King Kong merely presents a romantic tragedy, a tale of loneliness and persecution, and damn the details. King Kong is now such a part of popular culture that unborn babies are familiar with most parts of the plot, but, just in case you’ve been living on Mars for the last 80 years, here’s a quick run down. Both ‘real’ King Kong movies feature a bunch of movie producers and sailors travelling to an uncharted island (the tragically titled ‘Skull Island’ – bet their tourist board has to work hard) to make a film the likes of which the world has never seen before. Led by the obsessive director Carl Denham, his leading lady (Ann Darrow) is captured by the native skull islanders and offered as a sacrifice to Kong who, instead of eating her, decides he enjoys her company and carries her off instead. None too pleased with loosing their leading actress to a huge gorilla, the ships crew pursue Kong across the island to rescue Ann and encounter all sorts of vicious prehistoric beasties along the way, while Kong defends Ann from marauding dinosaurs, pterosaurs and snakes. Once Ann is rescued, Denham realises the dollar value of an 8 m tall gorilla and has him captured and shipped to New York. Once there, Kong escapes and reunites himself with Ann, but is ultimately chased to the top of the Empire State Building. With nowhere else to run, the cornered Kong is shot to death by biplanes and plummets to the ground.
Compared to the original, the 2005 Jackson effort certainly increases the emotional quotient of the story. Granted, many of the individual plot arcs of lesser characters are left unfinished or only partly developed, but the principle characters receive ample attention throughout the film. Carl Denham’s character differs little from film to film: a frustrated artist in both versions, Denham will stop at nothing to get his film and make his name and money. For him, the wonders of Skull Island serve only to grant him international fame and line his wallet, attributes he pursues with casual disregard for emotion or humanity. The character of Ann Darrow contrasts more markedly between the two films, however. In black and white, Ann starts screaming in fear from the moment she lays eyes on Kong until he’s plummeted to his doom from the Empire State in New York. As is typical of many pre-Alien monster films, the 1933 Ann is nothing but a victim, a damsel in distress waiting for the dashing Jack Driscoll (token squared jawed love interest) to rescue her from her beastly captor. This contrasts markedly with the Ann depicted in the recent version, who initially tries to escape Kong independently, orders him to stop tormenting her and, eventually, actually takes a liking to her simian protector.
Funnily enough, the character with the most humanity is Kong himself, a fact made all the more ironic because he’s neither human nor real. For the latter reason, both Willis O’Brien and the combined talents of Andy Serkis and the clever CGI chaps at Weta Digital Ltd. deserve mountains of accolade for bringing their respective Kong’s to life. Each is created with superb attention to detail and character, full of such subtleties of expression and motion that you almost forget you’re watching a rabbit-fur stop-motion puppet or a computer generated image. In both cases, Kong’s moods are conveyed through posture, movement and facial expressions with supplementary roars and grunts. Personally, I find his lack of dialogue serves to make him an even more appealing character and, indeed, my favourite bits of both films are the scenes with no words at all. As with the other characters, Kong sees greater development in the 2005 movie: his initial brashness and aggression towards Ann gradually fades and we eventually see that, for all his size and strength, he’s also totally alone. Similarly, despite his animal nature, Kong’s relationship with Ann embodies every positive aspect of human relationships, with each being totally devoted and willing to do anything to keep the other safe.
It’s a right shame, then, that the same ship that brings Ann and Kong together also brings his downfall. Seeing Kong in New York is a very different experience in each movie: the 1933 version essentially sees Kong go mad, trashing trains and squashing people even once he’s found Ann. The new version, however, sees the bold Kong panicked and confused by his new surroundings, a stark contrast to his attitude on his island home. In this version, Kong doesn’t find Ann; rather, she finds him and, in a role-reversal from Skull Island, it’s now Kong’s turn to rely on Ann for support as he explores the quieter streets of New York. Of course, it’s not long before the showdown atop the Empire State Building where neither Ann nor Kong can prevent the merciless biplanes from gunning him down. In these final scenes we see all the positivity and humanity represented by Kong and Ann coldly shot down by the extension of Carl Denham’s materialist values with consciences totally ignorant of their role in his persecution. Denham sums up this contempt for real humanity with his famous final line: delivered in a way that shows insight but little care, Denham acknowledges that it was not airplanes but, in fact, “beauty killed the beast”.
So, there you go then: how the favourite film of an eight-year old boy can be watched and watched until he turns a simple monster movie into a subject for an English Literature essay. I could go on but, holy crap, look at that: it’s nearly 1:00 AM. Best stop: it’s a school night. If anyone is still reading, thanks very much for all the kind words said about my pictures, essays and work in the last year: they’re always appreciated. Good night then, folks.
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Update (18/03/08): The nice chaps at The Future Soon have been bigging up the second year annivesary of my little piece of cyberspace (click your mouse here to see the post). For those of you unfamiliar with this blog, The Future Soon highlights all kinds of neat goings on in the world of science, from space exploration to freaky robots, nitty-gritty genetics to zoology and even science-inspired art. And they really like zeplins, which can only be a good thing. They're also key supporters of the pictures and words on this site, so thanks very much to them.
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Uploaded on Mar 14, 2008
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If you want to kiss the sky Better learn how to kneel (On your knees, boy)
By jiminy, there are a lot of fat people around nowadays. Apparently, one in five people in Britain are clinically obese: a worrying figure, but nowhere near as harrowing as the one in three obese people that offset the planet’s gravity in the U.S. I’m nowhere near being lumped into this category and, to be honest, I never want to be: not that I have a problem with other people carrying a few spare tires, you understand, but obvious health defects suggest that my scrawny build is preferable to the more spherical builds that can be seen roaming around my local high street. However, I do have cause to wonder whether obesity is as common as it’s reported to be: go shopping in any outlet store and the only sizes left of anything are extra-large and extra-extra-large. Having never really grown into a suit bought many years ago when I was still a lanky adolescent, I’ve spent the last few days hunting down a new suit that acknowledges my still-lanky adult build and, to my dismay, hardly any shops carry suits with jackets with 38 inch-chest sizes and 30 inch-wasited trousers. No, only extravagantly proportioned individuals to reap the benefits of discount shopping, leaving me a frustrated and suit-less individual. Thing is, it appears that none of these big people go the shops to buy this stuff: where are they all? Just where are these fabulously dressed supersized individuals that should exist if so many huge people are around? If obesity is rising, this is clearly an influential factor: all the small people are trying to gain enough mass to fit discount threads from the outlet stores.
It turns out that the sizes of some pterosaurs have been over-exaggerated, too. Some folk may be aware that some initital wingspan estimates for Quetzalcoatlus were well over 20 m, and a certain member of my research group would no doubt like to forget claims of a 25 m span pterosaur leaked a few years back (note that rationale and reason have tempered both claims: Quetzalcoatlus probably spanned around 10 m or so, and the footprints and ‘wing finger’ of the Gargantuadactylus [my term, not theirs] turned out to be bogus). Even wingspans for everyone’s favourite pterosaur, Pteranodon, have been overhyped at one stage: a bigass skull belonging to an older Pteranodon species than the pointy-crested form we’re used to was suggested to represent a Pteranodon spanning 10 m across its wings. In actuality, this robustly skulled form (P. sternbergi) was probably the same size as other big Pteranodon, spanning 6 – 7 m. Thing is, in an eerie echo of my rigorously tested fashion-based conclusions on overstating obesity, it turns out that most Pteranodon weren’t that big at all. Oh no: most were considerably smaller, and the explanation reveals a surprising amount of detail about the lifestyle of a long dead animal.
We’ve known about Pteranodon for well over a century – the first remains were found in the chalk deposits of Kansas back in 1870 by expeditions outfitted by the famous American palaeontologist, Othniel Marsh. In the years between then and now, well over a thousand specimens of this animal have been recovered and, subsequently, despite the fact that every Pteranodon fossil is squashed to wafer-thin proportions, we have enough specimens to form a pretty comprehensive idea about skeletal anatomy and gross proportions. Aside from its enormous, toothless jaws and striking headcrest, Pteranodon gained notoriety as the first truly giant pterosaur, an animal capable of competing with the wingspans of the aircraft being developed contemporaneously and pebble-dashing the size records held by pterosaurs from English Weald deposits. Pteranodon’s size attracted the attention of numerous aeronautical researchers trying to figure out how such an oversize animal could fly, and, as a brief aside, a consensus seems to have emerged that it represents an ultra-efficient dynamic soarer, cruising over the Western Interior Seaway that once divided the North American continent hundreds of kilometres from the shoreline. From a nice bolus of regurgitated gut content we know made its living by eating comparatively tiny fish, so, for once, the idea of a pterosaur mirroring the lifestyles of seabirds is sound. Finally.
Getting back to size, the notion of Pteranodon being a 7 m span giant has become entrenched in pretty much any piece of popular pterosaurs literature, so why should we start to doubt it now? The man to ask is Chris Bennett, the chap who we owe most of our modern understanding of Pteranodon to. Bennett has toured the globe in a quest to scrutinise, measure and identify every Pteranodon specimen available and left nothing but a trail of categorised and identified pterosaur bones in his wake. Such an analysis revealed a pretty startling fact: all specimens of Pteranodon can be neatly placed into one of two groups predominately differentiated by their size. The larger of the two groups (66 % of our Pteranodon specimens) contains the smallest individuals - forms with wingspans of no more than 4 m. All right, this is still much larger than any modern bird, but for a pterosaur, and a Late Cretaceous pterosaur at that (the Late Cretaceous is when pterosaur size really went nuts), 4 m is a very average wingspan. The other 33 % of our Pteranodon samples attained spans of 6 – 7 m, values far more familiar to those reading The Big Boys General Guide to Pterosaurs. Now, this could of course reflect different growth stages - year classes, perhaps - but close examination of Pteranodon bone texture reveals that our entire sample represents adult or close-as-dammit-adult specimens. Yes, dear friends: the plot thickens by the minute.
Not so close examination reveals that further details distinguish these groups: the smaller animals have much shorter headcrests than their larger counterparts, structures that can be as long as the jaw itself in particularly well-endowed individuals. The jaw tips follow a similar narrative: the big guys have prominently developed upper-jaws that end in blunted tips and overbite the lower by some margin, whereas the smaller have more equable upper and lower jaw lengths. Away from the skull, one further difference is found in the pelvis: relatively speaking, the small Pteranodon have deeper, broader pelvic canals than their oversize counterparts. These differences are not so marked in the ever-so-slightly-immature Pteranodon specimens and, apart from these differences in headgear and pelvises, the skeletons of each morph are essentially identical. Now, the lazy and boring explanation for all this is ever-so-slight speciation of Pteranodon species, but a far more interesting and plausible conclusion can be drawn: Pteranodon was sexually dimorphic.
I don’t know about you, but I think everything about this is unbelievably cool. Firstly, the very fact that we have enough data to deduce that Pteranodon was dimorphic is pretty amazing in the first place, but we can also make a damned good stab at figuring our which morph represents which gender. To do this, we need to investigate their reproductive business ends. Guys don’t really have to do much when it comes to reproduction – in fact, our reproductive gear requires very little muscle anchorage at all. Hence, a male Pteranodon would only really need a narrow pelvic canal to house the last vestiges of its guts and little else. By contrast, a female Pteranodon would have to lay eggs, requiring a broader pelvic canal to facilitate their passage. Seeing as we see relatively broad canals in the smaller morphs, we can make the assumption that the big Pteranodon are male, and the smaller ones female. With that sorted, we can make some comparisons with modern animals and draw some basic conclusions about Pteranodon mating behaviour based on the conventions of dimorphism demonstrated by modern forms. Neat.
Focusing on the males, then: what makes a male Pteranodon? Large body size and showy headgear, apparently. It turns out that there is actually a lot of variation in crest and jawtip shape and size: some males had straight crests when others were crescent-shaped, and some jaws were relatively pointed when others were blunt. The fact that immature specimens don’t have the headgear of fully-grown males tells us that they were only useful in adulthood, so we can hypothesise that they had some role in reproductive behaviour, the only behavioural category reserved for adults alone. Male Pteranodon may have flaunted their crests and jaws around in competition with each other for sexual resources and we might infer that, if competitive structures and competition intensity were as closely related as they are in modern animals, the large size of the display gear in Pteranodon indicates short, intense periods of inter-male competition. Furthermore, we (or, at least, I) might go so far as to speculate that their relatively massive proportions indicate that some contests came to physical bouts of strength, possibly explaining some of the injuries riddling various Pteranodon specimens. Furthermore, we can postulate that male Pteranodon were promiscuous buggers: strongly dimorphic animals tend to be polygamous, or, in other words, will happily have relations with multiple partners. We can imagine male Pteranodon competing with each other for harems of females or, alternatively, competing continuously until a cute little lady came over, quickly having his way with her, then returning to the fray to grab more attention while she flies off to develop and lay her eggs. Female Pteranodon, by contrast, have it relatively easy: with promiscuous males battling each other for access to their eggs, all they have to do is wait for the victor to see off his competition and await the delivery of the highest-quality Pteranodon sperm going - hence their smaller body size and lack of ornamentation.
Of course, a lot of this borders on speculation, but it is informed speculation based on some pretty solid observations on modern animals. Sure, we can never be sure that we’re totally correct in our interpretation, but the fact that we can make informed inferences about mating behaviour in any animal that’s been dead 80 million years is pretty remarkable on its own. If nothing else, it demonstrates how generalisations of fact – even something as simple as the size of an animal - can hide some pretty amazing details. Hopefully, the picture I’ve drawn above of a big Pteranodon sternbergi and his harem captures some of these points. Everything about the male is meant to reflect his competitive lifestyle: not only is he astoundingly big compared to his fairer sexed counterparts with a metre-long, robust skull, but he also bears an imposing dark integument to intimidate his rivals. Note that when standing he would be much taller than shown here: the picture shows him rising from lying down in the fashion demonstrated by long-limbed mammals: pushing off with his wrists and onto his back legs. This guy is meant to be quite old, too: hence the shocks of grey hair. I wanted to make him look like the last critter on Earth you would ever want to pick a fight with: I like to think the whole reason he’s standing up isn’t to run away from the impending storm approaching from the right, but rather to go show that storm who’s boss. Comparatively, the females are slender skulled, delicately built and lightly coloured: their colouring matches the functional constraints of their seabird-like ecology far more than the male’s. A few other details are included here: notice the absence of cliffs on this section of the Western Interior Seaway shoreline. Cliffs are often cited as necessary for pterosaur take off and, ironically, studies on Pteranodon are often the rationale behind such claims. Well, guess what, buddy: we don’t have any evidence of cliffs along the Western Interior Seaway (at least, not along the eastern side), so that argument may be flawed. Notice that there’s shingle on the mudrock, too. Ever see a pterosaur on a shingle beach? Me neither. So I thought I’d paint it. You know, just for kicks.
Anyway, this is already too long. Thanks to all those who’ve already commented and said nice things about the picture – most appreciated. Incidentally, this picture has been drawn to feature in a top-secret project being worked on by the yuppies of the pterosaur world. Along with myself, it involves he likes of internet palaeontologists David Hone, Darren Naish and John Conway: Darren's Tetrapod Zoology (just celebrating it's second birthday, dontcha know) may well be known to lots of regular readers, but less well known may be Dave's (and, um, the University of Bristol's) Dinobase, a collection of all sorts of information on everyone's favourite Mesozoic reptiles. Be sure to check out the forum on this site, too: many of Dave's deepest neuroses can be found therein. Finally, John's artwork and projects are a must for anyone who wants to understand pterosaur anatomy and see amazing images of pterosaurs and some other ancient beasties. Right, that should do for now. Until next time, so long…
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Uploaded on Jan 24, 2008
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Festive peril at the Witton household
And look, John Lennon's there too. Or is it Shaggy from Scooby-doo?
Merry Christmas, happy New Year and other festive pleasantries, folks. I'm pleased to say that I've had a most enjoyable year: thanks to all of those out there in Flickrville and other recesses of the Internet who've been very kind and supportive along the way. It's unlikely I'll get anything posted before 2008, so, until then, best wishes and enjoy the holidays. That's an order.
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Uploaded on Dec 17, 2007
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That you may see the meaning of within
My long suffering housemates, Graeme Elliott and Richard Hing, have to put up with a lot from me. Along with my incessant nagging about cleaning, shutting the front door properly, closing the freezer door, taking back rented DVD’s, taking their washing out of the drier, broadcasting their foibles across the Internet and a bunch of other things, they also have to put up with some really, really, stupid ideas. Like when they offer me a choice of paths when we go walking in the woods; one sunny and bright, well worn and accessible, and the other dark, dingy, rocky and treacherous. Naturally, I choose the latter, thereby guaranteeing that we get lost and spend several hours wandering across private property, climbing fences, contemplating fording rivers and hacking our way through thorny bushes with penknives. There was the time I got stuck in a big pit in Spain and Graeme had to yank me out by my arm. And the time I dragged Graeme up a mountain with overturned rocks just to say we’d been to the top. Oh, and walking up Snowdon with 25 kg of camping gear (each) on our backs. It’s little wonder that the picture inserted here (for those of you who don’t know, Richard is the man clad in denim while Graeme is the magnificently proportioned chap next to him, leaving me as the bespectacled thing on the right) is one of the few pictures in existence of us all smiling – and I think the effect was only achieved here with assistance from howling Dartmoor winds. Hmm.
The latest silly idea I sprung on these two was a grand artistic extravaganza, an evening dedicated to sitting down and depicting whatever we happened to be thinking about at the time. The plan was, y’see, that the house really needs some decoration: something to put some colour on the walls. Like most people, we’ve got the odd picture and dried turtle carcass up here and there, but, generally speaking, the walls are a bit bare. So, when talking to Richard about surrealist images one day, I figured it would be a really great idea to spend an entire evening collectively working on décor for the house, producing on three independent images that could then line the hallways or lounge or wherever. Being present at its conception, Richard was privy to the idea from the start and was surprisingly happy for the whole affair to go ahead, but pitching the notion to Graeme was a little more difficult. Having lived with Graeme for 5 years, I know that art and drawing are not really his thing and, subsequently, an evening of doing nothing but that might not be his idea of a swell time. Still, my sales pitch and food-based bribery must’ve worked relatively well (all the more surprising considering that the conversation took place while I was browsing in the vegetable aisle at Tesco and he was filing out of a football stadium at the time – I might add that this conversation took place on mobile phones) because, on Sunday night (that’ll be the 25/11/07 for all you folks from the future reading this), the three of us converged in the dining room and replaced placemats with big sheets of paper, cutlery with artistic implements, and, oh, wait - we kept the coasters for drinks. Still, point is: we sat down to draw.
Now, I had another reason for doing this. I mean, I could probably churn out enough pictures to cover the walls of the house if I really wanted to (I’m working on my office at the moment, mind), but I was genuinely interested as to what Graeme and Richard would produce. I’ve seen both produce scientific images for reports and write-ups throughout our university studies and am the proud possessor of a Richard Hing original surrealist piece, but that’s about the limit of my experiences with my housemate’s art. Hence, the evening was arranged to be as mutual appealing as possible in order to get creative juices flowing: we had a choice of music, one full CD of our choosing each, to play during the session to tease creative magic from our hands. There were drinks and nibbles on tap. A variety of paper sizes, but unfortunately not colour, were on offer, as was the limited variety of artistic media that I could rustle up on my meagre budget. My interest was, y’see, to find out what methods would be used to produce the images as much as much as the pictures that would be drawn. Both were under instruction not to plan anything to draw too rigidly: the whole event was meant to be very spontaneous. Come 20:00 or so, all things were in place. Would the two of them dance in their seats in the way that I do when drawing? Would they even be sitting down? Would they sing? Would they produce bold, daring pieces full of colour or muted, subtle works? And, hey, I guess I had to produce a picture too, so what would I get up to during all this? Suffice to say, I was rather excited to see how the evening turned out…
Musically, choices were actually rather predictable: no-one revealed a secret love for lounge jazz or Tibetan opera or anything. The first CD, Graeme’s choice, was In Time: The Best of REM 1988-2003, which certainly got Graeme singing along (and me mouthing the words to the odd tune) but received a relatively muted response from Richard, suggesting that the lyrics were a bit ‘whiny’ on occasion. I must admit, fond though I am of REM (I have got the same album somewhere), Graeme’s music lacked the punch to really get me going and ended up providing little more than background noise. Next up was Richard’s choice: XTC’s Skylarking. Having heard XTC’s turn as the Dukes of Stratosphear, I was genuinely interested in hearing more of their work, but, again, it didn’t really move me that much. That’s not to say I didn’t like it, you understand, but it didn’t really lend itself to standing around drawing. Richard, on the other hand, launched into several impromptu drumming sessions and danced around in his chair admirably (a much safer place for Richard to dance, incidentally – it’s much harder to fall over in a chair). On the other side of the table, however, came innumerable voices of complaint: Graeme insisted that the music was dull, poorly sung drivel, and reaffirmed his opinion that Richard’s musical taste is by-and-large awful and ‘bordering on offensive’. Most predictable, though, was my choice of minstrels for the last album of the evening: U2’s excellent, excellent 1997 alternative album Pop. Full of all manner of sensual, touchy-feely songs that are absolutely ace to draw weird, twisted crap to, it is without a doubt my favourite album of the moment. Graeme picked up the odd lyric here and there (particularly on the awesome Staring at the Sun) while Richard found it a rather lagging end to the musical ensemble of the night, saying it was a bit dreary. Apparently, Graeme found Pop added to his flair nicely, presenting the drive to add all manner of detail to his picture that XTC lacked. As for me, U2 had me squirming around like a man possessed, singing ever so quietly and having a very good time indeed (I was, after all, leaping around on tippy-toes by this point). Despite the late hour, the third album suddenly woke me up and I probably did half the picture in the last 50 minutes.
As for media, choice here was varied. Graeme insisted on working small – as small as he could, in fact. Short of a tiny little pad that I carry around to knock the odd sketch out in, there aren’t many pieces of paper smaller than the A4 piece Graeme used to do his work on in the house. Richard, too, stayed relatively small by using A3. I did something a little different, using a piece of tea-stained canvas about 80 x 120 cm (or so). As such, Richard and Graeme remained rooted in chairs all evening, while I had the perfect opportunity to dance around like a twit when working - I’m sure I was the only one to work up a sweat during the whole night. Further distinctions were seen with choice of implement: Graeme and Richard stayed true to trusty old pencils, while I used pastels and charcoal. Of course, this reflects experience as much as anything else: neither Graeme nor Richard habitually draw pictures, so it’s perhaps expected that they should work on a smaller scale with more controllable media than someone who counts this sort of thing as his main hobby.
Approaches to the pictures were very different. Graeme never took his feet from the ground in terms of his inspiration: everything he drew has a basis in reality and the logo for Jerry Bruckheimer Films (there was even lightning and a tree at one point – seriously. Check out his work in the top right of the image above). Graeme has often commented that he ‘likes landscapes’ and finds it incredibly difficult – if not impossible – to produce a random, unhinged image. Changes to Graeme’s work were not made because the picture ‘evolved’ from its original conception, but because of ‘limited technical ability’ (his words), but everything remains recognisable. In fact, Graeme informed us that he was more-or-less reproducing a part of his drive home, which can’t be said for either the image that Richard or I produced (God help you should you have to drive through either of those). Richard’s approach was quite the opposite of Graeme’s (and, coincidentally, located opposite Graeme’s in the image above) – there’s neither a basis in reality nor a cohesive theme to his image at all: the only link between all the pictures is that they’re on the same page. It is, at his admission, a collection of doodles on a loose landscape, including a collection of impish figures in the lower right, dancing desserts, a parliament of trees, a few constellations and, predictably for those who know him, an owl. Oh, and the most alternative view of the Empire State Building you’ve ever seen. Richard’s imps were the focus of much discussion: apparently drawn to be very jovial and gay, Graeme saw mostly malice in their form and I, along with the aforementioned malice, saw several macabre disfigurements including a lady whom, fresh from the horseracing at Epsom Downs, was decapitated and had her head surgically attached to a sick jack-in-the-box-come-wheelchair construction. Um… moving swiftly on, there is undeniably a much more light-hearted feel to Richard’s image than either that produced by Graeme or myself, and it’s random, scattered-landscape pretty much sums up Richard’s mindset, too. Richard is, after all, a man who offers people chocolate logs on a whim and suggests, when you least expect it, that he might take a bag of the compost we’re producing back to this home in Hereford just to spice things up a bit. He also finds it difficult to stay focused on work for any great amount of time and is prone to wonder very random things. Likewise, Graeme’s image matches his mentality well. Preferring to dwell on real issues and forms, Graeme finds recognisable features in everything to grant things names and labels – each of the imp-figures in Richard’s picture received a name based on their resemblance to other things, for instance, as did ‘Dire Straits Man’ in my picture. This is not to say that everything has to have meaning – Graeme was going for drama with his picture, sure, but I don’t think he meant it to convey any real message. Similarly, Richard’s three alternative image titles (er… Woodland Fruit Strudel, The Pentacostal Beanery and A Play in Two Parts. A Marveilous Straunge Fische [sic] - see for yourself in the top left of his picture) suggest that he doesn’t attach much poignancy to his work. Actually, Richard’s picture really reminds me of the cover of a school workbook at the end of the year, covered in the idle doodles of an infantile mind - which I mean in the nicest possible way, of course.
Once the pictures were finished at midnight-ish and we’d all sat/stood around listening to the soundtrack from The Wicker Man (not much drawing took place during it, y’see, hence it’s omission from the earlier discussion), I asked my chums if they found the whole experience very relaxing. I mean, I can’t think of anything much more relaxing that drawing or sketching (well, maybe a much sought after lazy day on the sofa…) or, at least, any activity in which I feel more content. This is not the same for my colleagues, however: Richard said he was largely indifferent, whereas Graeme said he found it very hard to relax at all while drawing. Again, I guess this kind of response might be expected – after all, neither Graeme nor Richard are the types to spend an evening hunched over a pad of paper, which they no doubt would be if they felt as comfortable with the whole thing as I do. Still, most unexpectedly, the prospect of a follow-up evening has not been ruled out. Who knows: in a few months, you might have the results of a second night of mad scribbling. As it is, this bizarre way of spending a Sunday night provided a neat little insight into the heads of my good friends and housemates and I expect their images to adorn the walls of the house soon. What’s that guys? They aren’t going up? Well, you shouldn’t have let me make digital copies of them, then…
--
Oh, and finally, there is a deliberate lack of commenting on my own picture here. Having pulled their pictures to pieces and made all sorts of inferences about them, I feel it only fair that I invite Richard and Graeme to level the similar comments at my work and myself. This may be a very, very bad idea.
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Uploaded on Nov 26, 2007
11 comments
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