Posts Tagged 'research'

On review papers

Papers that act as summaries, syntheses of data, or basic, outright reviews are both important and successful parts of science. The prominence and importance of journals like the Quarterly Reviews in Biology and especially Trends in Ecology and Evolution shows their relevance, and let’s not forget that classic academic texts like The Dinosauria or Romer’s Osteology of Reptiles are more or less reviews of the existing literature. Yes of course there are new interpretations tacked onto these and corrections made to taxonomies, anatomy and the rest, but mostly they are a compilation of the most important and significant papers on the subject and present a consensus view of the current scientific positions.

Reviews are really useful. After all, it’s impossible or at least exceedingly hard to dive into a new subject (or even keep up to date effectively, or simply refresh your memory) from scratch. This is true of course for academics, but also for students of all levels, technicians and the general public – we all have to start somewhere. Review papers (in general) provide a foundation on a subject, giving the first principles of the issues at hand and the outline of what is known and how and what it means. It is not an end in itself, anyone with serious pretensions to work in that subject should be reading much further and wider, but this will be the place to start and of course provides a great resource for a given topic.

However, oddly it seems an awful lot of journals don’t really like publishing them. While there are dedicated review journals out there, my recent experiences with them is that they are overflowing with submissions or requests by people to produce submissions, so clearly lots of people are writing them or want to write them. The huge interest in things like TREE and the massive citations accrued by papers in them or something like the Dinosauria shows people are using them. However, a great many journals simply say that they will not publish reviews, or review-like manuscripts (or similarly useful things like catalogues of specimens, lists of localities or whatever). We seem to be in the odd position where people want to write something, readers recognise their value, they are widely used and cited, but the journals don’t want them.

Moreover, even the review journals can be difficult when it comes to reviews! A paper of mine was ultimately rejected from QRB because one referee demanded that we include new primary data and an analysis of this. I don’t disagree that a review can still contain new data and new ideas, but really? A review paper in a review journal has to contain new work and analyses? Even those that do publish seem to go in for either the tiny (TREE papers are just a few pages) or the monolithic (Annual Reviews in Earth Sciences) with little scope for something say in the 10 page range.

A few more journals willing to accept such manuscripts or even a couple more journals dedicated to reviews would seem to benefit all and sundry and I for one hope this can be encouraged.

On why I really, really dislike all things that rank papers

It’s a long one, best get a cup of tea and make sure you’re in a comfy seat… Ready? OK.

Science has long struggled to rank the worth of the actual science itself. There are all kinds of metrics to rank journals and papers and the contributions of authors. I have yet to meet one that I don’t profoundly dislike and it really all comes back to the same central point in that all of them seem to be so massively dependent on factors that have very little to do with the actual quality or use of the research. I also know that (and understand why) hiring committees need quick and dirty ways to cut through several hundred applications to a few dozen and these kinds of things will scream out at them for use. I am, frankly, worried that I (and many other colleagues) might be missing out badly for no other reason that these metrics can be biased against or towards various kinds of research or researcher, regardless of their actual ability or the quality of their work.

Have a few too few citations or lose a few points on an index and you might never make the shortlist no matter how good or valuable your research is. Moreover, this will promote practices that are at best, not conducive to good science.

Let’s start with the recent version set up on Google Scholar (for those interested, here’s me). This is pretty standard as they go, it looks at my citations, top papers, and a couple of indices that basically look at how often my papers get cited. I have a few problems with some of the things it’s doing at the moment and it’s new and needs work, but the basic principles are the same here as on other metric sites.

So what’s the beef? If my work is good and is being read and cited then my ranks will go up right? Well yeah, in theory. But are these things happening correctly? What things might skew how often (or rarely) a paper is cited (or counted as being cited) and how relevant is that?

First off, there and obvious one. If you’re cited in a paper you get one citation. But someone whose work is critical to a manuscript might be cited dozens of time, but a single tangential point or general review paper might pick up a mention somewhere. Both are scored equally – one citation. So right off the bat, two papers can appear to be equal when they are not. I was recently delighted to get a copy of the new Scipionyx monograph from Cristiano Dal Sasso. Included was a note telling me I was being gifted a copy as I was one of the most cited authors in the paper. Only 1 of my papers was cited in a reference list that ran to something like 400 papers – so in short on this occasion at least a single ‘ping’ for me doesn’t represent the significance of the paper.

Secondly, things can be cited often even if, or even because, they are wrong? How many papers are there out there on birds and their dinosaurian ancestry which mention the BAND group? Most of them give it at least a token mention in their introductions, which means the same half dozen BAND papers rack up the citations even though they are only ever being cited by people saying they are wrong! On a not unrelated note, a big pool of papers that make the same point may be sampled more or less at random (no need to cite 50 papers to say birds are dinosaurs) or the same few pick up all the hits, even if there are better or more appropriate ones out there.

There’s also a lot of journals out there which simply don’t get picked up by the indices at the moment because they’re not considered of sufficient calibre or are simply rather obscure and so citations in those journals won’t be added to the list. You can make a case that if only minor papers are citing your work then it can’t be that important, but I think this isn’t right. After all, the biggest journals count just as much as the smallest ones, there’s no direct rank by journal quality, and I’d argue there’s a bigger gap between the biggest and smallest journals that would count than between the lower ones that are ticked off and the best that are not.

Subject with numerous researchers are likely to rack up the citations far faster than smaller research groups. There are probably four or five people working on theropods for every one who works on pterosaurs, so assuming people publish similar papers at similar rates, theropod papers might get four citations for every one a pterosaur paper picks up, even if both are of hypothetically similar values in quality and usefulness. Chance can play a big part here too, I remember a theropod-worker colleague of mine noting wryly that his one paper on a mammal (a tooth he’d happened to find in the field which turned out to be very important) had accrued more citations than his entire back catalogue of dinosaur research combined.

Some of these ranks are dependent on rates of citations too, or only count those accrued within the first 2-3 years of publication. Well again, some journals are much faster than others, indeed some entire fields are. I know in some branches of science, 2-4 weeks in review is normal, and submission to publication can be in weeks. There are few palaeo journals that are not measured in many months for those kinds of turnaround times, so it’s simply harder to get a few citations that quickly.

So all of these have obvious problems. Someone can write a terrible paper on HIV say, but with lots of researchers out there, and all of them keen to stick the knife in, it could rack up hundreds of hits fast in major journals. But a truly brilliant and groundbreaking paper in a relatively obscure palaeo journal on a subject with only a handful of specialists might take years to get half a dozen. According to these indices (or for that matter an outside observer or non-expert) the former will look much more appealing than the latter.

Moreover, these things can also be manipulated, or at least have the potential to be. People can cite themselves where they don’t need to, to get a few more hits in. Cartels might form of people citing each other to jack their citations up, or supervisors (or even referees and editors) can pressure people to cite their work. People might start splitting big papers into multiple smaller ones, each of which can then cite a few things and bulk the number up again. Or you can put each other on your papers to bump up the number of papers you have apparently contributed to and get all the free citations that go with it down the line. A brilliant student might still struggle to get papers published in good journals if they are not getting the support they should, and a poor student can be gifted credit on papers in major journals by a generous and talented researcher (and I know the latter already happens – it’s dispiriting to meet an alleged author of a paper and discover they don’t speak English, or on one memorable occasion, realise they are on the paper you’re talking to them about….).

Other metrics have been tried or are being considered, like numbers of views or downloads, or number of pages published. Again, this will vary enormously between different fields but can also be screwed up. I remember my Microraptor paper coming out and a colleague got it early and e-mailed it to a couple of massive mailing lists. Within minutes, hundreds of researchers had a PDF (whether they wanted it or not). A few days late I checked the PloS metrics and according to that about half a dozen people had downloaded it, and only a few dozen had visited the page. But then that would happen, no-one needed it because they already had it! But not to worry, it could always be jacked up, just set it as a required reading for a course taught to a few hundred undergrads and the numbers can soon skyrocket. Or be savvy enough to get it pimped on the right media site and you can drive thousands of people to the page.

What about numbers of pages published? Stick to small format journals, make sure your figures are big, pack in extra references and use some nice big tables. The number of pages will soon go up.

In short, I have yet to see a metric which is anything but highly capricious and makes no real measure of all of these problems. Bad papers in popular fields with fast turn around times and short manuscripts will surge ahead of a field with few researchers who tend to turn in long papers of superb quality. Moreover, there’s an obvious risk of escalation – people can start tailoring their work to these ends, focusing on more popular fields, keeping papers short, bumping up their citations (especially to their own work or those of close colleagues) and so on. None of this is good for science.

Discussions with a number of colleagues show that hiring committees, promotion boards and grant bodies are actually using these metrics, or ones like them, to decide things like who gets money or a job. For someone working in a field where turn around times are huge, papers often long, and the number of colleagues small, you can see why I’m worried. I may be competing for positions with people who have apparently a much greater academic record simply because they work in a popular field. I can’t and don’t expect a prospective employer to read, let alone understand, a whole bunch of papers on theropod ecology, HIV transmission and fish mechanics, but equally, if you’re only evaluation is an H-index or the number of citations in 2 years it’s clearly weighted (or can be) for one field and against another. Sure, a theropod researcher is going to spot the better student of a pair or people working in the field, or understand that the egg specialist is likely to suffer from a lack of citations compared to the maniraptoran worker, but that’s always been the case.

I freely admit that there’s no obvious solution (better minds than me have looked I’m sure). And yes, there is certainly something to be said for these metrics: good papers will, I’m sure, on average, get more citations than bad ones. But at the same time I think it’s hard to look at these and how they are built and think that it is entirely fair and ‘on average’ is fine until you discover you’re the one at the end of the statistical tail and are getting shafted by it. Some fields, some people, are going to suffer. And these look like they can be manipulated relatively easily in ways that will not benefit the subject but will those who bother to do so.

Where are my papers?

Let’s face it, it’s been a while since I had a good complain about something, so in the usual holiday manner (the spirit is  supposed to be merriment, but let’s face it, the tradition isn’t!) here’s someone grumpy complaining. There’s another moan to follow tomorrow but I’ll sweetn the deal by following this with comments on theropod sociality and my reviews on the zoo and aviary in Pittsburgh.


It’s customary for me to whine about reviewers and editors periodically and for once it has been a while since my last effort. However, the Christmas break has allowed me to try and catch up with a few little things, one of which has been to see what has befallen various papers I’m involved in and if there has been any news of them. While I do have a pretty large volume of manuscripts with various journals, to be honest it’s not pretty reading. Now sure there are valid reasons for papers being delayed (and of course the Christmas period doesn’t help), but you would hope that the occasional paper would run to time, or be processed in a timely manner.

By my count I currently have 9 manuscripts in out with journals. Of these, based on the ideal review times listed by the journals or what I can remember when being asked to review for them, 8 are now late. The last one will be late if it’s not back to me this week and I have good reason to think it won’t be.

There are couple more which have recently been returned, one in a timely manner and one late, and there are a couple of book chapters which are literally years overdue. More than that, despite contacting editors about them, in some cases I have no news at all what is happening to the paper (including one submitted in July!) and in one case the manuscript is awaiting assignment of referees when it is a resubmission. You’d assume they’d be sending the paper back to the same people, and even if they refuse to review something a second time, does it really take three months to send them out?

In short my manuscripts are late by the standards of the journals themselves. In more than one case things are profoundly late, and in a couple I can’t even find out what has happened to the manuscript. Referees seem to run late as a near matter of course and often they are given months toe review something a handful of pages long anyway, something that annoys me profoundly. But when papers aren’t even being sent to referees for weeks, even months, it’s very annoying. Even if a referee is superb and turns around a review in a few days, if it didn’t reach him for weeks, or the review doesn’t reach me for weeks, then the whole thing is going to be late. It’s especially when journals try all these little tricks like publish uncorrected proofs and the like to get the papers out as early as possible. So, it’s clear they value a paper that’s ready for publication being hurried into availability, but then they make no effort at all to actually have papers edited or refereed in a timely manner.

Now sure, maybe this is happening to everyone, but really is that an excuse? As I’m fond of saying about this, writing that review, or mailing out to ask for referees, or check a set of corrections or whatever takes the same amount of time to do today as it will in 2 weeks, or 6 weeks or even 6 months. And while you might be busy this week, and even next, I don’t think it’s excusable to sit on something for months at a time. It does the author a disservice and for that matter both the journal and the field as a whole. Science is not served by papers, perhaps important papers, being held up by months, even years, because people won’t do the work they said they would.

Is it really this bad for palaeo, or am I profoundly unlucky? Looking back over my past papers and various submissions I would say the average review time for a manuscript of mine is about 5 months, and I’ve had half a dozen that were over 6 months from submission to return. Conversations with colleagues suggests that I have had some bad luck and the extremes I’ve occasionally suffered (over a year on 2 occasions, and several more over 6 months each) are the exception. Even so, I’d be intrigued to know what this is like for my colleagues and indeed for those in other fields of science and research.

Archosaur Musings 2011 roundup

Well as it’s the end of the year it’s time for my annual roundup of the last year’s trials and tribulations of my research and palaeolife. I’ve been generally ticking along well this year in terms of post numbers, at least in part because I’ve had a few major trips that have yielded much new material to blog about and I’ve been in the field less than previous years. As such I’ve been able to maintain nearly a post a day for the whole year which I’m rather proud of. Sticking with generalities, this year saw the Musings hit 500 000 visitors (and now closer to a million than that figure) and I passed a thousand posts too. The palaeoart interviews really took off this year and the guest posts continue to trickle in, most notably the second half on Darren Tanke’s superb Gorgosaurs series. Finally in just the last week I’ve signed up to Twitter which I hope will boost my outreach still further (like I really need that).

Moving on, as per usual I’m moving month-by-month, if mostly because it’s the easiest way of trawling though a whole years worth of posts to see what happened when and what’s worth commenting on. As usual, this is a personal list and deals really with things I did or that happened to me rather than

January saw the description of the little alvarezsaur Linhenykus. Notable for having just a single finger on each hand this was a great little thing to see described. While I can take fully no credit at all for it’s discovery, this was a paper that I was involved in from start to finish and was pleased to see it go through.

February saw the publication of a paper on science communication and my Ask A Biologist site (this is available here on Open Access for the next few days at least for those who are interested). AAB was started really because I wanted to do it and thought it would be useful, and it has grown enormously in the last few years. As such it was nice to get something more tangible personally from it by publishing a paper on the successes and failures of the site and to try and encourage other academics into committing themselves to outreach projects. This month also saw my first trip of the year to China, effectively to sign-off the formalities of my three years there and complete the necessary paperwork and interviews to ‘graduate’ with a formal postgraduate qualification from the Chinese Academy of Sciences (though I’m still waiting for the certificate).

Little happened in March until the last day of the month when I was finally able to bring the world Zhuchengtyrannus, an event that ran through much of April. Obviously this was incredibly popular as this was a new, large tyrannosaurine. For me though, it was the first dinosaur I’d named as the lead author and well, what a taxon to start with – there’s not to many of them out there. In hindsight it’s also a bit odd given the extensive training in taxonomy and systematics I’d had as a student and the work I’d done on pterosaurs and dinosaurs that I’ve yet to name any pterosaur and it took half a dozen taxa before I got my own dinosaur (as it were).

May saw the publication of my collaboration with the SV-POW crew on the alleged sexual selection of sauropod necks. It was a long process to get it there and after years of working on both it was somewhat annoying and frustrating for it came out just a few months before my most recent paper such that Darren Naish and I had to gazump our own paper and slip some mutual sexual selection commentary into this one. More importantly though it was good to really dig into sexual selection and try and get to grips with the subject and its importance to animal ecology.

I returned to China in June, this time for most of the summer and so June and July saw me in Dublin, London, Beijing, Zhucheng, Urumqi, Osaka, Okayama and Toyko. That meant that I was seeing dozens of specimens, carrying out my first fieldwork in Xinjiang, seeing major exhibits in museums and more. It has produced ammunition for a ton of posts and more importantly, a number of papers, at least a couple of which I hope will be out in 2012.

September was a very mixed month. On the upside, it was my first SVPCA in far too many years and as usual it was a superb meeting and I had the opportunity to catch up with a number of old friends and colleagues and get some important projects moving forwards. On the downside, it marked the end of my contract in Dublin, and for those who didn’t know or missed the hints, I am now unemployed. I realise economics are a bad time for all, but well, academia and especially science in the UK has been hit hard so it’s a terrible time to be job hunting. I’m not out of the game yet, but after 15 years of training, you would kinda hope to have a career at the end of it.

Being back in London did allow me to finally get out to Crystal Palace though and October saw my first ever trip to the historic creations in the park and see them. It was genuinely exciting and they were impressive and interesting in their own right, regardless of their obvious importance to the way dinosaurs were first brought to the public.

November brought another major first, my trip to the US and more specifically the Carnegie in Pittsburgh. I have Mike Habib to thank for his generous hospitality and in supporting my trip out there. This was a great opportunity for me to catch up with Mike and also Matt Lamanna, as well as indulging in the superb exhibition halls and getting down with their pterosaur collections. It was truly a superb week.

And so finally to December. Obviously things calm down here normally, though the appearance of my paper on mutual sexual selection in dinosaurs and pterosaurs was a great way to round of 2011. Started back in 2007 (or even 6 perhaps, I can’t really remember anymore) it’s finally come to fruition and for me it’s a very important piece of work and I’m delighted to have seen it through. Now to get the rest of my unpublished papers published. There’s only a few dozen things need finishing off in 2012….

Mutual sexual selection in dinosaurs and pterosaurs

As of last night my latest paper has come out, coauthored with Darren Naish and Innes Cuthill. Those with access to the journal Lethaia can get it here. Believe it or not I’ve been juggling with the idea as to whether or not to blog about this for quite some time. This is, I think, the most significant paper that I’ve produced and it’s the product of literally years of work (though at least part of that was as a result of very difficult editors and referees at various times, this was started back in 2007!) and I’m really rather proud of it.
Then why not blog it? Well the short answer is that this is a long and complex paper and it ultimately deals with a huge range of difficult issues (and not in the length we’d have liked, it had to be cut down severely to fit the journal and we still incurred page charges). It touches at various times on pterosaurs, sauropod body size, various ornithischian lineages, theropod sociality, the origins of feathers among other themes. All of this means that it’s very hard to blog about and cover the salient points for a non-expert audience without writing thousands upon thousands of words and, well, I did that for the paper.

This is obviously counterintuitive for a blog that is effectively about science communication, but I can’t do everything all the time (I certainly haven’t blogged all of my papers of the last few years). Moreover, in my experience, a paper like this which rather stomps a bit over some much cherished hypotheses of people tends to attract huge number of comments along the lines of “but what about *this* contrived example!” which I can assure you gets very annoying when people won’t let it drop.

None of this means I *won’t* be blogging it at length. But I know it’s likely to be covered a bit elsewhere on the web and thus it’ll look odd that I’m not doing it right away and it seemed sensible to provide an explanation up front. What I will at least talk about it mutual sexual selection – it’s right there in the title and the abstract and is, I suspect, a concept unfamiliar to most, perhaps nearly all, readers. it is after all, something almost entirely absent from the literature on dinosaurs and pterosaurs, Darren and I could only find two other references to it ever and one of those was what we put into the Taylor et al. paper on sauropod necks and the other sprang from Portsmouth. So it’s something that’s only really just coming into the literature.

Sexual selection is probably familiar – the idea that some traits are selected for by the opposite sex and can drive the development of bight colours, crests. displays and all manner of other things. The obvious one that’s endlessly used is the train of a peacock, that makes the male look very different to the drab female. This is typically coupled with sexual dimorphism (again, like the peacock) where the male is bigger than the female and has the extra ornaments etc. and males compete for females, with the best ornaments males advertising their fitness through the size and quality of their fitness (though in some cases like jacanas, this is reversed with bigger females).

So far, so simple. Mutual sexual selection is simply an extension of this into both genders. Both males *and* females are ornamented (or rather, have sexually selected traits) and just as males are competing with other males for the best females, so too the females are competing with each other for the best males. This means that dimorphism is limited or even absent – both genders having such traits. This is in fact, well known for quite a number of bird species and the number of papers on the subject in living species is increasing in leaps and bounds.

In the paper we hypothesis that this may have been common in the ornithodirans. It explains (potentially) quite a lot and solves a couple of previous paradoxes about crests evolution and development. Critically it means that you *don’t need* dimorphism of a feature for it to be sexually selected – both genders can have a crest and it can still be a sexually selected feature. This needs testing, this paper does little more than lay out all the conceptual issues and evolutionary biology and ecology behind the hypothesis, but at the same time, I think we do have some pretty good support for our ideas.

But as ever, what really needs to happen is for you to go and read the paper! And yes, I do have a PDF if you want it.


HONE, D. W., NAISH, D. and CUTHILL, I. C. (2011), Does mutual sexual selection explain the evolution of head crests in pterosaurs and dinosaurs?. Lethaia. doi: 10.1111/j.1502-3931.2011.00300.x

Reserving Specimens

A while back I mentioned that I had sort of ‘reserved’ the new pterosaur specimens in Toyko to work on. This practice is pretty normal in vertebrate palaeontological circles – there are only so many specimens available and it can take a lot of time and money to go and see something. If you spend that only to discover that someone else is already publishing on that material then it’s rather wasted and your funding body may not be too impressed.

As such if you have an invitation to work on something or have seen something and the curator has agreed that you can work on it, the unwritten rule / general consensus is that this is your ‘exclusive’ specimen and no one else should work on it without permission until your work is done. This can apply as much to revisions of old material as new specimens but the general idea is the same. Obviously if you come across something and are informed that someone else has ‘reserved it’ then you need to get in touch with the ‘owner’. Naturally, many people are happy to collaborate on something, or are happy for people to do minor work like code something for a phylogenetic analysis, or even carry on as normal if the work is completely non-overlapping (say you want to take a histological sample and the other guy is only interested in skeletal proportions or doing and FEA analysis of the skull). In theory at least this also means that if you can’t get the work done for whatever in a ‘reasonable’ amount of time, then you should make it clear and let any circling people into the fold and let them do their work (and if they are being generous, they should try to involve you).

When this all works, it works well. People can guarantee they won’t be gazumped after writing a grant or spending all their cash to do a piece of work, and others know what they can and can’t do in advance. People can collaborate or tailor their projects to build up a piece of work or avoid toe treading and feelings can avoid being hurt. Of course there are those who either cling on to stuff they can’t (or won’t) work on and there are (true) horror stories of specimens being withheld for decades while someone (allegedly) works on them and at the other end, some people try (and even succeed) in publishing on things they have been told other people are working on. It is imperfect, but in my experience at least it generally leads to much better working practices and less confusion and paranoia, than simply declaring anything up for grabs.

Finding the fliers – pterosaur discoveries

Having spent a couple of posts talking dinosaur discovery rates, it seemed worth musing for a few lines on the same phenomenon with regards to pterosaurs. As noted, new pterosaurs are being discovered at only about a quarter of the rate of new dinosaurs, though given that there are far fewer pterosaur than dinosaur researchers and the overall greater rarity of pterosaurs, this in fact probably represents an overall relatively higher rate of pterosaur discovery even if the absolute numbers are lower. That is already quite significant to my pterosaur-centric mind and belies the pterosaur revolution we seem to be undergoing.

On a slightly cloudier note, the ongoing controversy and problematic taxonomy of a number of groups or genera does mean that it’s likely that a number of these new taxa will be sunk back into obscurity. While obviously this is the fate of some taxa in all groups, to my eye the pterosaurs to tend to do a bit worse in this area that do say the dinosaurs. Still, when just a few years ago Dave Unwin surmised there were only around 110 valid pterosaur genera after nearly 200 years of research, the fact that we have been able to add around 20 more in the last three years alone is stunning. Next year might well provide a bumper harvest too with the next Flugsaurier volume due.

While they’re never going to get the same attention as dinosaurs, the last decade for pterosaur research really does point to a quiet revolution. We have more active researchers now than ever before (and by a fair margin) and we seem to be drawing in more attention from other workers (that is, there are quite a few dinosaur and archosaur guys who dabble with pterosaurs when in the past they wouldn’t have done so) and we’re getting together regularly too and producing whole volumes of papers. We’re seeing not just a huge increase in the numbers of new genera, but even entire new clades like the boreopterids and chaoyangopterids, unexpected late surviving toothed taxa, and of course Darwinopterus makes quite a difference. There are also major increases in our knowledge of older taxa – there are lots more anuroganthids and azhdarchids than a few years back, and other discoveries are adding massively to our knowledge. You’d struggle to find even a handful of really good specimens with soft tissues a decade ago but now we are positively blessed, and we now have 4 pterosaur eggs (and three of them with embryos) when before 2004 we had none.

At the risk of a little hyperbole, I really think we are in the midst of something special happening with pterosaurs and I genuinely think that in a few decades we will look back at the time between around 2000 and 2020 as the time when we really got to grips with these taxa and much of our knowledge settled into a familiar pattern. There will of course be more surprises and changes to our ideas, but this is very probably the beginning of a new age of pterosaur science and their renaissance (which dinosaurs had in the 80s and 90s) is begun.

Discovery rates

I talked yesterday about the rate of discovery for dinosaurs and the almost overwhelming mass on new taxa that are constantly appearing. While this is inherently important, what’s more interesting is what this can (or rather cannot) tell us about the total number of dinosaur species that might be out there. In short, 175-ish years since dinosaurs first started being found and recognised as such there has been no real sign of discoveries slowing down and in fact the rate looks to be picking up. With new and important localities in Australia, Argentina and Asia looking very profitable, this might accelerate still further. Even allowing for synonymy we are obviously getting quite a lot of new dinosaurs right now.

In the past people have attempted to predict the total number of dinosaur species that might be out there to be recovered (and obviously that;s not the same as how many there were – not all of them would have entered the fossil record or be identifiable). However, this rather relies on knowing how the discovery rate is changing and also it might change in the future. The rate of discovery of species of all kinds (both living and fossil) follow pretty similar patterns (as shown here rather well on Tet Zoo). They start slow, then shift into an exponential phase and eventually as researchers get near the limit of species to be found, this tails off and flattens out as it takes more and more work to find fewer and fewer species.

The thing is, as long as you are in the exponential phase of discovery, it’s impossible to tell when then tail off is going to be hit. It could be in a couple of years, or it could continue for decades. For the moment, all we can say is that it’s still going up, fast, and with no tail off in sight, we can expect these kinds of discoveries to keep coming. It’ll be some time yet before we can start to think about knowing just how many dinosaurs are out there to add to our taxonomic list.

Darren Tanke’s Gorgosaurus preparation: final roundup

I have been less than brilliant at cross-linking all the various Gorgosaurus posts that have been running now since December and finished yesterday with Darren’s final summary and update. It seemed sensible then to have a final little round-up on here back linking to all the previous posts and giving a central repository for everything up to this point.

I also want to use the opportunity to repost a few of my favourite images from the series which are scattered in below. Of course I also want to give huge thanks to Darren for all his work on this. I’d originally conceived of the series of being little more than some nice pictures shows the rock slowly clearing to reveal the underlying dinosaur with a few notes on what was going on. Darren obviously has gone way beyond this with a huge series of detailed posts and documenting every step of the process and every little trick and tip he has going. My thanks too, to the Royal Tyrell Museum for letting us do all of this and stick this, as yet undescribed, specimen all over the web.

Right, here we go:

Continue reading ‘Darren Tanke’s Gorgosaurus preparation: final roundup’

The grey literature

No piece of work is immune from error, and I’ve rarely seen any paper without a mistake in there somewhere if you dig deep enough, even if it’s just a typo. Even so, the point of peer review is to iron out papers and reduce the amount of mistakes and maximise the amount of accuracy. Given the review and editorial process, this makes the scientific literature proper rightly the primary source of research material and information for academics.

However, while the vast majority of what you will (or should!) see cited in a paper is other academic papers this is not the only source. The point of citations is of course to allow other people to track down your information source and not everything is in the scientific, or primary, literature.

At the other end of the scale we have popular literature. Non-reviewed and quite probably non-expert written material. Normal dinosaur books aimed at the public, news articles, bits in magazines, and these days most blogs (including this one) and the like.

However, somewhere in the middle we have what is often called the grey literature. It’s written by an authoritative source and was probably checked, if not actually reviewed, by other professionals. It might contain detailed references and ‘proper’ figures with scale bars, detailed labels, contain specimen numbers and so on. Things like Peter Dodson’s “Horned Dinosaurs” or the “Complete Dinosaur” book and similar fall into this category. So too to various articles in some journals (like opinion pieces, book reviews and the like) and, in all probability, the really solid and referenced blogs like Tetrapod Zoology.

There’s nothing wrong with citing any of these in a paper, in theory at least. And if your only source for a given point or bit of information is the ‘Jumbo A-Z of dinosaurs’ then so be it. However, it’s not what you should be going for if Smith et al. in a paper in Nature is available. No paper is perfect, but much like the concept of argument from authority, it’s generally better to head to the primary literature, though it’s not always possible.

A less good but more important Pterodactylus

To emphasise the point of my other post on this exceptional Pterodactylus, here is another specimen from the Solnhofen Museum. This one may not look as nice as the other, but the bones are preserved closer to an original 3D state. More importantly, although you can’t see it here, numerous soft tissue parts are preserved. An anterior crest, and occipital ‘cone’, a partial beak and claws and skin around the feet.

So while this little critter may not have the obvious aesthetic appeal of the last one, this is probably the more important and significant specimen scientifically.

The pterosaur mandibular fenestra part 2

Yesterday I introduced the problem of the ephemeral mandibular fenestra of ptersaurs and wondered where it might have gone. Based on the paper out the other day that Sterling Nesbitt and I wrote (well, Sterling wrote, I helped out) we reveal what we think happened.

Firstly the Eudimorphodon specimen with the medial fenestra, is this real, and does it extend externally? The answer lies in several different areas. First off, the may not be Eudimorphodon. The specimen was described in the days before Raeticodactylus and other pterosaurs with Eudimorphodon-like teeth but that were not Eudimorphodon. Several things were tied to this taxon based on their teeth when hindsight suggests this was not a great idea. If we assume this is not Eudimorphodon (and there are reasons to think so) then the problem of fenestra-free Eudimorphodon specimens disappears.

Secondly, the jaw is not in medial, but lateral view. This is a genuine mandibular fenestra that fully penetrated the jaw. This came about thanks to Sterling’s superb eye for detail when he noticed that the sutures of the bone for the various jaw elements just didn’t match up with the medial pattern seen in other archosaurs, but was very similar to that seen on the lateral face.

Archosaur mandibular fenestra. From Nesbitt & Hone, 2010.

This is interesting news in itself, but still leaves us with the problem of a non-basal pterosaur with an apparently primitive jaw condition when none of the things that came before kept one. Not impossible, but certainly odd. Enter Dimorphodon. Way back when the great, and, let’s face it, a bit nuts, Richard Owen wrote a description of various Dimorphodon specimens he noted that one may have had a mandibular fenestra. However, noting himself that other pterosaurs seemed to lack one, he wrote this off as an internal one revealed by missing bones at the back of the jaw, just as Wellnhofer did over a century later. Again, revisiting this specimen and a third with new ideas means it looks very much like Dimorphodon had the same thing going on. Now we have two taxa with fenestrae, including in Dimorphodon, a very basal pterosaur.

This at least suggests that this really is a hang over from the ancestral archosaurian condition and that it was then lost several times in various pterosaur clades, though probably quite quickly given how rare it seems to be. This then is our, not actually all that helpful, but ultimately quite interesting, solution to the question of the problematic Swiss Eudimorphodon. Come in mandibular fenestrae, you time might just be up. (Possibly, and with the full knowledge that this really won’t go down well in at least a couple of pterosaur researcher camps).

There are some other bits in the paper on pterosaur origins and the distribution of various characters. In short you can get good mileage from difficult problems from new specimens and of course ideas can change as the available data increases and changes. To get more you should read the paper. Happily, it’s freely available, so off you trot to here to get your copy.

Nesbitt, S.J. & Hone, D.W.E. An external mandibular fenestra in pterosaurs supports placement within Archosauriformes. Palaeodiversity, 3: 225-233.

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