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Becoming More Like Alfie
Image by Mark Witton
My housemates don’t quite understand my fondness for darkness. While it probably does my eyes no good at all and has led to more than one stubbed toe, I don’t put many lights on around the house. At best, I’ll put on a few lamps while drawing or reading, but I can’t stand ‘big’ lights. No, they’re too artificial, too orangey and somehow nowhere near as pleasing as genuine sunlight. I’m not one, y’see, for pretending that it’s not dark outside: in fact, there’s something quite comforting about being at home with the dark only held at bay by the localised glow of a little lamp. It’s the same feeling you get when sat indoors as rain lashes against your windows. You know the one: that warm, comfy feeling that’s amplified by the sound of rain peppering the glass and brings a smile to your face every time some poor bugger runs past, soaking wet and miserable, while you’ve got your feet up on the sofa and a cup of coffee in your hands. This means that as the nights draw in and temperatures drop in this October time of year, I’m quite happy to embrace the change. Still, it does mean that we’ve got to wave goodbye to all the summer hobbies and open the box on all the wintery, indoor counterparts. Goodbye snoozing on a lazy common under a clear blue sky, hello lazing on the sofa in front of the telly. Out goes watching bands on the seafront, and in comes piping your favourite tunes through the internet. So long to cycling around town looking as stereotypically French as possible and welcome to... well, actually, that will continue unabated: some things should persist all year, after all.
Of course, our transfer to winter conditions occurs quite slowly, caused by little more than successive subtle changes to rainfall and temperature over many weeks. In this respect, it operates in a similar manner to the classic model of evolution: successive generations of organisms build up incremental changes to their anatomy over time and, eventually, produce something radically different from their ancestors. We don’t see much evidence, certainly in the fossil record, of organisms dramatically changing isolated elements of their anatomy without effects elsewhere: they don’t, generally speaking, suddenly develop an entirely new skull structure or something without showing modification of other body parts. What’s weird, though, is that geneticists have found that genes – and the expression of them - often show signs of clumping together into genetic complexes or ‘modules’ that, in theory, could be modified independently of other modules to produce large changes to an organism’s bodyplan without affecting others. Typically, we don’t see such changes in the fossil record: organisms typically show a whole bunch of ‘advanced’ and ‘primitive’ features scattered across their anatomy, so called ‘mosaic’ evolution.
All this changes today, though. Stepping into the international spotlight is Frank, a new pterosaur from the middle Jurassic of China that combines features of pterodactyloid pterosaurs (classically defined as critters with reduced numbers of openings in their skull; long, simplified neck vertebrae; long bones in the ‘palms’ of their hands; short tails and reduced fifth toes) and their more basal ancestors (defined by the inverse of the criteria listed above). Of course, ‘Frank’ isn’t the animal’s real name: honouring 200 years since Charles Darwin’s birth and the 150th year since the publication of The Origin of Species, it’s been christened Darwinopterus; but the moniker ‘Frank’, used by the scientists studying Darwinopterus to refer to the animal while they were thinking up something more grandiose, does reveal something about it’s strange anatomical bauplan. Frank’s anatomy, see, is somewhat akin to the construction of Frankenstein’s Monster, looking like it was bolted together from different pterosaurs. More specifically, the head and neck are classically pterodactyloid, while everything below the neckline is a textbook basal pterosaur. Frank is therefore important for at least two major reasons: it’s the first time in over 200 years of pterosaur research that we’ve gleaned an insight into the transition of pterodactyloids from basal forms, and, perhaps more importantly, it shows that this modular evolution stuff did occur and can be demonstrated in the fossil record. Frank’s discovery has other implications too but, I’m afraid, we don’t have time or space to cover them here. Happily for you though, you lucky dogs, I’ve penned a full summary of how Frank will shatter the world over at the online science magazine Flesh and Stone: why not nip over there and read it now? Just be sure to come back.
Right: got the full lowdown on Frank? Pretty neat, huh? Such an interesting little critter clearly deserves an equally interesting press release image and, presumably because all the other palaeoartists were on holiday or something, Frank’s minders asked me to produce that image for them. I was asked to focus on two things: Frank’s hybrid pterosaur bodyplan and it’s proposed ecology of an aerial predator. I have to admit that this proposed ecology doesn’t sit entirely comfortable with me: it’s not that I’m saying the authors are wrong, but there’s been virtually no research at all into the functional morphology of non-pterodactyloid pterosaurs and, as such, their assumption of things like their poor terrestrial ability lacks backing. What’s more, for all it’s modular innovation, Frank’s anatomy is quite generalised and there’s no features to really suggest it was a specialist aerial predator. That said, a number of birds manage to hawk animals in mid air without specific adaptations for the job, so Frank’s proposed ecology may get through on this technicality. Plus, at least it’s not another suggested fish eater or, God forbid, another proposed skim-feeder, and that should be celebrated. And, undeniably, aerial predation makes for a more exciting PR image than, I don’t know, grubbing for worms.
Frank’s portrait went through quite a few drafts before the version you can see here. The first decision involved deciding on a prey item: if you’re a mid-Jurassic aerial vertebrate predator, your menu will consist of gliding dinosaurs, mammals or other pterosaurs. The obvious choice had to be a dinosaur because, in these cynical times, dinosaur-eating animals tend to get more press interest. Once this was decided, composition had to be considered. Initially, Frank was powering in from the right of the image, mouth agape and wings at the end of their downstroke. The prey item was different, too: rather than the gliding troodontid Anchiornis seen here, Frank was chasing a tiny scansoriopterygid, a group of very birdlike dinosaurs that appear to have been adept climbers. In fact, the first draft of Frank’s image saw Frank about to engulf one of these chaps as it ran up a tree, but my commissioners were dead keen to retain Frank a predator of other aerial animals, so the scansoriopterygid took to the air in a parachuting fashion for the next draft. This version almost became the final draft, but two big changes were then asked for that resulted in the whole thing being started again. Firstly, Frank was found to look much better at the top of the image, looming over his prey with raised wings and using it’s long neck to reach beneath it. Then, re-dating of fossil beds containing Anchiornis gave us the opportunity to jump on the ‘isn’t it cool to have genuine dinobird in the mid-Jurassic’ bandwagon, and gave us a more topical and likely prey item. To begin with, this version had Frank flying directly at the viewer, meaning his chest obscured much of the detail of his anatomy. This didn’t really cut the mustard for showing off Frank’s chimeric characteristics, so he was repositioned again to appear as in a dive. Anchironis, too, once looked more birdlike, but this was toned down to ensure that people recognised it as a dinosaur. Once all this was settled, colouring finally commenced and, in tribute to the cut-n-shut processes taking place around Frank’s neckline, I thought it made sense to have a clear division between the dark basal pterosaur anatomy at the rear and the considerably brighter, funkier pterodactyloid anatomy ahead. Anchiornis was made deliberately bland to contrast with all those dinobird images that have them painted in the same schemes as the most brilliant birds of paradise: I’m sure there were fantastically coloured Mesozoic dinosaurs, but there were probably plenty of dull, brown ones too. I figure that I’m already working on a reputation for making pterosaurs less interesting (they weren’t hyperlightweight, had relatively uninteresting feeding strategies etc...), so I may as well try to make dinobirds boring, too.
Beyond this, a background had to be painted. The Tiaojishan Formation rocks that yielded Frank are much better known for their palaeoflora than fauna, suggesting that it would’ve been very, very green around there 160 million years ago. A lush, vegetated background was clearly needed then, and my initial plan was for the backdrop to be painted with a directional blur. You know, as if the image were a tracking photograph of Frank and his prey that grabbed the animals in focus but blurred the background. However, I opted away from that in favour of experimenting with some depth of field stuff that, with it’s grading into mist and fog, also serves as a subtle nod to old Chinese ink and wash paintings. I think it works. Sort of. That being done at the end of several weeks – maybe even a couple of months – of sketching and redrafting, the image was ready for presentation at the big SVP conference in Bristol last month. I think it’s generally all right, but there are some bits that could be better: Frank looks a little flat and undershaded, and some parts just look unfinished (apologies to the authors – deadlines and all).
And on that note, I’ll finish. Don’t forget to check out Flesh and Stone for more Frank-related goodies if you haven’t already, as well as their other articles on all things science. As for me, this year’s transition from summer to winter has churned up a very nice looking day, so I’m going to have a shower and enjoy the warmth of the sun for a while. Probably while drawing one of the dullest pterosaur fossils in the world. Oh well: can’t have everything.
Image by Anton Novoselov