Gravity cannot reach us anymore
I'm a big fan of recycling. Any rubbish we have around the house is a candidate. Bottles and jars? In they go. Polystyrene and foam packing? That's in too. Food waste? Compost it. Bottle tops? Well, not really meant to, but I figure if I keep throwing them into recycling waste then someone, somewhere, will eventually get the message that they should be recycled, too.
In keeping with this spirit, I'm not going to write anything new to go with this image: I'm going to recycle something from elsewhere. All you need to know before diving into this second-hand text is that the image above depicts a Pteranodon taking off, but obviously using its arms, not its legs, as the main launch propulsor. This may seem a bit odd, but read on and all will be clear.
The first stage of achieving flight, of course, is becoming airborne. As alluded to above, quite how pterosaurs did this has long been a problem and running starts, gravity, headwinds and/or different atmospheric conditions have been pulled in to help. Whilst there is little evidence for the latter, you can just about scrape an argument together that pterosaurs living in coastal or marine environments may have been able to find enough cliffs or wind to regularly employ them in takeoff, but the same certainly cannot be said for the increasing numbers of pterosaurs turning up in inland continental deposits. Inland settings are often very flat, windless and densely vegetated places that really limit the potential for finding suitable pterosaur runways. It’s particularly interesting that the real pterosaur giants, the azhdarchids, are most abundant in terrestrial settings too, as they presumably needed the longest, widest runways, strongest headwinds and sloppiest slopes to takeoff: it’s hard not to wonder just how many places these guys could conceivably take off from under such constraints. Adding further fuel to this quandary is the recent calculations by two teams of authors that suggest pterosaurs massing above 70 kg (Chatterjee and Templin 2004) or even 41 kg (Sato et al. 2010) were unable to launch at all, regardless of environmental assistance. These masses are strikingly low when the arguments on pterosaur mass outlined above are taken into account and, moreover, the widespread distribution, longevity and apparent volancy of all known pterosaurs seems to suggest their flight was not so environmentally limited. In short, then, our problem is thus: how did realistically massed pterosaurs become airborne without the luxury of a Mesozoic airport?
The answer, it seems, comes from the fact that we’ve been looking at only half of the picture. It has always been assumed that a pterosaurs launching from a flat surface will have taken off in a bird-like fashion, using a leap or a run to attain the velocity needed for flight. While this assumption may appear quite safe and, indeed, the strength of pterosaur hindlimbs have been noted (Bennett 1996; Padian 1985), two American pterosaur workers, Jim Cunningham and Mike Habib, have long pointed out that assumptions of bipedal launch contradict other evidence (e.g. Habib 2008). For one thing, it’s notable that walking and launching are achieved using the same gaits in birds and bats: birds walk and takeoff bipedally, whilst bats do the same tricks as quadrupeds. We may expect, ergo, that pterosaurs may have also stuck to their quadrupedal gait whilst taking off. Similarly, it turns out that launching with the hindlimbs alone seriously pumps up the leg skeleton of the launcher: bird legs scale much faster with mass than other parts of their bodies - even their wings - to meet the demands of shoving their weight into the air with only one set of limbs. Pterosaurs, by contrast, do not have particularly robust legs for their size but do bear strong, overscaled forelimb bones that are particularly well-developed around the shoulders (Habib 2008). Under mechanical analysis, these bones are more than strong enough to catapult twice the weight of a given pterosaur into the air, whereas their hindlimbs would fail at much lower stresses.
What this all points to, then, is the high probability that pterosaurs took off quadrupedally and, in all likelihood, from a standing start. Firstly, the pterosaur would crouch before shoving up and forwards with its hindlimbs to vault over its own arms. Almost simultaneously, the powerful forelimbs push upwards, changing the trajectory of the pterosaur body from one moving primarily forward to one moving forward and skyward. Whilst this is occurring, the wing finger is being extended out to open the wing and, as the animal becomes entirely clear of the ground, a partial upstroke is achieved as the arms are swept above the shoulders. The wing is fully open by the end of the upstroke and full flap cycles can begin, which the pterosaur would continue as it ascends to a suitable height. All this would take place in a very quick, highly synchronised fashion and even the largest pterosaurs would be clear of the ground in a second or so.
Such a sight would certainly be worth shedding out some cash to see and it’s worth taking a quick moment to consider the prospect of a giraffe-sized monster azhdarchid launching itself into the air in this way. What’s more, while this may sound like the latest in the long line of crazy ideas that have been proposed about pterosaur habits, bear in mind that a number of bats (most famously vampire bats) launch in a very similar fashion and, because they employ the most powerful muscles in their body –those developed for flight – their takeoff is particularly powerful and efficient (Schutt et al. 1997). In fact, little vampires almost spring into the air vertically, a trick, it must be said, that would not be seen in larger pterosaurs. With greater masses to heft into the air, climbout angles would decrease as size and mass increased, meaning the largest pterosaurs would require a relatively clutter-free area immediately in front of their launch site. Still, it would seem odd for large, gangly, volant animals to hang around in woodlands or forests anyway, so this probably wasn’t much of an issue. The evidence for quadrupedal launching appears pretty convincing, then and, if sceptics need further evidence of this behaviour, there are rumours of a trackway that may show a pterosaur taking off in just such a fashion (Habib, pers. comm.. 2010).
Pretty neat, huh? If that doesn't stir your palaeontological loins, nothing will. Before we go, though, a word on the source of that text: eagle-eyed readers will have noted references to preceeding text that was not reproduced here and, clearly, there's a list of cited literature associated with the piece, too. Where did it come from, then? Well, folks, you've just read a short excerpt of the first draft of a book that I'm currently writing: yup, after years of people telling me to write a book, I've finally picked up a pen - er, keyboard - and got cracking. It exclusively covers pterosaurs, unsurprisingly, and is intended to be equal interest to researchers and interested layfolk. Princeton University Press will be publishing it next year and, with 100,000 words and 200 illustrations planned, it should be capable of holding open even the weightiest of doors. It's planned to be about A4 size and most pictures are in colour, so it should look reasonably pretty too. While we're all here, actually, anyone comments or suggestions about the style of the text above will be appreciated: too technical? Too patronising? Too verbose? This is, after all, a book aimed at you (yes, specifically you. By the way, you have a little food next to your mouth) so any comments will be welcome.
Right, best get back to work. The hardest part of the whole thing awaits me: I've still not decided exactly how to start it. A tangential discussion of lamposts, perhaps? Or maybe how cookbooks always list 'chicken mince' as an ingredient and yet I've never seen it anywhere in the shops? I'm sure that's an allegory of something in pterosaur research. Probably.
Uploaded on Aug 29, 2010
This somehow seems apt. Sort of. Why not sing along?
Good evening one and all we're all so glad to see you here
We'll play your favorite songs while you're all soak up the atmosphere
We'll start with old man river, then maybe stormy weather, too
I'm sure you know just what to do
On with the show good health to you
Please pour another glass, it's time to watch the cabaret
Your wife will never know that you're not really working late
Your hostess here is Wendy, you'll find her very friendly, too
And we don't care just what you do
On with the show good health to you
Petina, start the show at 2 o'clock
And if by chance you find that you can't make it anymore
We'll put you in a cab and get you safely to the door
But we've got all the answers, and we've got lovely dancers, too
There's nothing else you have to do
On with the show good health to you
You're all such lovely people dancing gaily round the floor
But if you have to fight, please take your trouble out the door
For now I say with sorrow, until this time tomorrow
We'll bid you all a fond adieu
On with the show good health to you .
More details on this madness here.
Uploaded on Jun 25, 2010
Take me out and show me off, Put me on the scene
In recent days my place of residence, the small coastal city of Portsmouth, has been inundated with craploads of snow, freezing temperatures and icy conditions. This is really unusual: Portsmouthonians usually consider themselves lucky to see a few snowflakes, let alone four inches of the white stuff across pavements, parked cars and roadways. At first, this was undoubtedly the Best Thing Ever, with the closing of the university offering ample opportunity to engage in snowball fights, build nicotine-addicted snowmen, walk in virgin snowfalls to hear the neat crunching noise that snow makes underfoot and, well, do other snowy things. Four days on, however, our Winter Wonderland has transformed into a New Year Nuisance, with chief aggravator being the transformation of the soft, snowballable snow into packed, two-inch thick sheets of ice that adorn pavements and road surfaces around the city. While some main roads were gritted and cleared, the majority of the city’s streets have been left alone, making even a run to the supermarket far more adventurous than it need be. Even without the hazards of slipping over (which is mostly just an embarrassing annoyance, but something I’ve considered a little more seriously since seeing a blood-splatted, fractured ice sheet yesterday evening), it doesn’t half slow you down. I walk quickly, y’see – I’ve got things to do, places to be and regular need not to be late for work, after all – and become frustrated very easily when shopping crowds, ice or other dense, amorphous obstacles slow me down. I’m the walking equivalent of a reckless driver, moving too fast, cutting people up, performing risky overtaking manoeuvres and all: how can I do that when there’s all this ice around? I can’t, obviously, and it’s really getting on my nerves.
In this respect, the current state of Portsmouth is a metaphor for the early days of the Internet (yes, really). Remember that period back in the mid-nineties? Back when you had to listen to your modem whistling as it connected to your Internet provider, downloading your favourite Walking with Dinosaurs wallpaper in 1024 x 768 resolution took a month of Sundays and the entire Internet landscape was decorated with poorly animated GIFs? Moving around the Web was so slow: particularly image-intensive pages gave you enough to enjoy several cups of tea, listen to your favourite Suede CD and watch a classic, mid-nineties episode of The Simpsons whilst it downloaded. Still, armed with nothing more than a 56K modem and a big-assed monitor, we took our first turgid steps into the land of filth and procrastination that is the Internet and, back in those days, there were several big palaeontology sites that my gawky adolescent form liked to visit. Many of which have since become defunct, but I fondly remember wading around the Dinosauricon (including that fantastic art gallery), the embryonic Dinosaur Mailing List, early versions of Dinodata and Palaeos, Dinosauria.com and some, long forgotten place where I scored a bounty of Gregory S. Paul skeletal reconstructions in some weird format known as a ‘PDF’. It’ll never catch on, you know.
Nowadays, of course, the Internet is a very different place. The Interweb of the mid-nineties is like a meandering country lane compared to the superslick, ultrafast Web 2.0-Facebook-Myspace-full-streaming-HD-video-YEAH! motorway that we now browse on. The amount of palaeontology on the net has skyrocketed, a feat aided by the invention of blogs, the ease with which websites can be created and the way in which high-quality E-information can be passed around so readily. Of course, a lot of these sites are of suspect quality, containing out-of-date or sparse information or reflecting the opinions of the authors disguised as scientific fact, but there are several Palaeo-themed blogs and websites maintained by level-headed, knowledgeable folks that provide reliable information and intelligent analysis. Problem is, while there is a Pantheon of E-information available on dinosaurs, other fossil groups are really neglected online, including those most loveable of non-avian flying reptiles, pterosaurs. So far as I can remember, there has never really been any truly exceptional, dedicated pterosaur websites. There have been and, indeed, still are some very good ones, but most fall short in not keeping up-to-date with pterosaur science, provide really skimpy information about very interesting things and, crime of crimes, provide archaic, horrendous restorations of pterosaurs in life. As such, finding out things about pterosaurs online has always been difficult but, thankfully, this is all about to change. Well, maybe.
Y’see, some time ago – 2007, to be exact – the pterosaur yuppies of the world decided to unite and, rather than using their vast intellects and good looks for evil, cobble together a pterosaur website that would reflect up-to-date pterosaur research, provide information on more animals than just Pterodactylus and Quetzalcoatlus and use accurate reconstructions of their anatomy and life-appearance. The role call for this exercise included a bunch of household names in the pterosaur world: vertebrate palaeontologists Dave Hone, Darren Naish, Ross Elgin, Lorna Steel, Helmut Tischlinger, Dino Frey, Michael Habib and palaeoartists John Conway and Luis Rey offered to lend their pens, artwork and domain addresses to the cause and, somewhere along the line, I was offered some jobs too. The result is the appropriately titled Pterosaur.net, a compilation of articles, and images of all things pterosaur. The site is not entirely finished, but, seeing as it has already taken a couple of years to get this far, we figure that there’s enough there to cast our Internetvessel into the sea to see if she floats, with odds and ends to be added later.
So, if you cruise over to Pterosaur.net, what will you find? It’s all pretty self-explanatory, really, and easily navigable with the two menus at the top and bottom of every page. The main sections see Dave Hone introduce the group, give a run-down on pterosaur systematics and a brief glimpse at pterosaurs in popular culture; Mike Habib reviewing pterosaur anatomy and attributes of their flight; me giving a typically long-winded account of pterosaur terrestrial locomotion and palaeoecology; a variety of authors introducing select pterosaur genera; John Conway revealing how the life appearances of pterosaurs are restored from their fossil remains; and Darren Naish explaining how much of typical pterosaur portrayal in the press and fiction is pure bumph. But that’s not all, little chickadees: we have a fossil gallery that doesn’t just show you images of fantastically preserved, three-dimensional pterosaur remains, but also Helmut Tischlinger’s fantastic photographs of Solnhofen pterosaurs taken under UV light. There’s another set of pterosaur restorations by two of the top pterosaur artists of modern times, John Conway and Luis Rey, with my work in there to demonstrate just how good these guys are. Dave Hone has scoured the web to provide a list of half-decent pterosaur websites and you can read all about the aforementioned pterosaur yuppies with our short contributor biographies. Although it’s not up and running yet, there’s the beginning of a Pterosaur.net blog, too: while many members of the Pterosaur.net team already have their own internet soapboxes, this provides a place to post pterosaur-specific news. The best bit of all, though, is that we want to hear from you: following the methods provided in the 'Contact' section, you can E-mail Pterosaur.net’s creators and tell them what you think. The site has been designed to be constantly modifiable, so, if we receive constructive feedback, we can tinker with the site to make it more accessible and informative.
So, there you go, then: a new, pterosaur-specific website put together by people who, hopefully, have some idea about what they’re talking about. Of course, some folk may have already seen the site: it’s actually been live for a while, but today marks its ‘official’ launch where we’re directing the world to its figurative doorstep. If you have already paid a visit and perused our list of neat pterosaur taxa, you may have noticed the above image features alongside Ross Elgin’s words on Anurognathus: I’ve had this image knocking about for a while (it was commissioned back in July 2009 and, in the final version, it sits alongside a giant azhdarchid to demonstrate pterosaur size range) but, to date, had no time to do anything with it. It’s easily my best anuroganthid image yet – though that’s not saying much – and incorporates all the newest data on these critters afforded by a sexy new specimen from the Solnhofen limestones (check out the Fossil Gallery at Pterosaur.net to see a brilliant UV image of it, complete with glowing traces of it's muscles) would discuss these here but, frankly, I think this post is long enough as it is. Before I finish, though, I should say that while a lot of people worked hard to bring Pterosaur.net into being, two folks deserve a particularly large pat on the back: Dave Hone, the man who took the main organisational reigns of the project and John Conway, the guy responsible for building such a functional, fantastic-looking site and an editing platform that even dunderheads like me could log in and use. Thanks to them, then and, as for anyone still reading at this stage, I only have one question for you: why’re you still here?
Uploaded on Jan 10, 2010
Trouble in the Message Centre
Once again, months have flown by without a new post: that wasn't meant to happen. I've got at least two new images that I want to put on here soon, but finding the time to write something of note about them has proved more or less impossible. A not unnoticeable affect on my free time has been the impending arrival of Christmas: this means it's obviously time for another E-card thingy to be posted up here. This one comes with a festive warning comparable to those given in Dickens' A Chirstmas Carol: if you're going to send said E-card to your friends, family, colleagues and acquaintances, it's a jolly good idea to make sure the E-card is attached. Otherwise you send out your biggest E-mail of the year and look like an ass.
Merry Christmas and Happy New Year to you all, anyway.
Uploaded on Dec 17, 2009