Archive for December, 2011

Lambeosaurus

While I’m clearing out old photo albums, here’s a cast of the Lambeosaurus head. Well, I rather assume it is, I’m not that familiar with the more obscure hadrosaurian crests and this does look about half-way between a Corythosaurus and Lambeosaurus. A quick skim of Lull & Wright suggests it’s more like L. magnicristatus than anything else, but it’s still not *quite* right for that either.

It’s held in the basement at Eichstaett and they don’t seem to know where it’s from beyond ‘Canada’ or which specimen it’s based on / taxon it’s supposed to be. Anyway, it is a nice one and something I’ve not seen before (perhaps no surprise given the paucity of hadrosaur mounts in Europe) and lacking anything else to go up till New Year it’ll have to do!

The Archosaur Musings 2011 awards

As usual to round off the year it’s time for a bit of fun, so here’s my take on the last 12 months in archosaurs.

Most important new archosaur discovery

There’s not been much this year that I’d truly class as being the most important find of the year, the kind of thing that will still be making headlines or leading papers 20 years from now. I guess the combination of a new Archaeopteryx and Xiaotingia will go a long way on the subject or bird origins for quite some time to come.

Best newly discovered archosaur specimen

Has to be a Darwinopterus with an egg. Great pterosaur specimen it it’s own right, but that’s a hell of an addition with it.

Best named new archosaur

I’m rather taken with Spinops, so this one is going to Andy Farke and colleagues.

Worst named new archosaur

I’m not giving this to Zhuchengtyrannus simply because it wasn’t my choice of name!Instead it goes to Unwindia. I know it was supposed to be a bit of a gag, but really it just sounds weird.

The ‘Similicaudipteryx’ award for lest original archosaur name

Last year I wrote “I know Xu Xing doesn’t read this, so I’m probably quite safe plumping for Tianyuraptor. It’s a raptor from Tianyu. Great.”. This year brought us Linehnykus and Linhevenator to join Linheraptor. Oh.

Most egregious media error on archosaurs

Hard to pick out anything specific, but pretty much everything written about Xiaotingia and ‘Archaeopteryx isn’t a bird!!!!’ was pretty poor. It was, to be fair, not an easy subject to get to grips with, but so many people failed so magnificently it was a real shame.

Best media report

I’ve really not read that much this year for popular science which is a shame. As such there’s nothing stand out in my memory for the last year. That’s not to say there was not good, even great, media coverage of the archosaurs at times, more I can’t point to anything I remember as being, well, very memorable.

SVPCA long time no see award

I got to catch up with a lot of people this year who I’d not seen for ages, most especially Don Henderson and Matt Carrano. A great year for renewing friendships and research plans.

The ‘about time’ award for slow publication

My own mutual sexual selection paper. First hinted at in a 2007 Flugsaurier abstract it’s taken 4 more full years to see the light of day, mostly down to horrible refereeing (the kind that was so bad other referees complained about it and the editor still accepted the criticism). Delighted it’s out, annoyed it was delayed by probably 2 full years by bad refereeing and editing.

Ridiculous prediction for 2012

Having gone for flying troodontids and feathered sauropods I might be starting to run out of mad, but just about plausible, concepts. However, in a couple of different places ‘flightless pterosaurs’ have recently come up again, so I’ll go with that.

And finally it’s been made quite clear to me that I’d better have an award ready for ‘best dinosaur biscuits’ after these came my way. So here it is.

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….

Rex heads

Following my last few posts clearing out my archive of photos of theropod skulls here’s a couple of Tyrannosaurus heads in near ventral view. The upper one is from Oxford and has, I think, a nice background in the glass roof panels, while the lower image is from the IVPP in Beijing.

Monolophosaurus

This is a rather better photo of the skull of this theropod than I’ve managed before, and with my recent paper on dinosaur crests now out, it seemed a relevant time to post this up. Monolophosaurus is famous for having quite a large crest of bone along the midline of the skull that runs from the front to the orbit – it’s rather hidden here as the shot is taken from a low angle, but you can see the enlarged naris and parts of it above the antorbital fenestra.

For a theropod, this is really quite a large crest which might sound odd, but in fact makes a lot of sense. We sort of discuss this within the sexual selection paper but in hindsight we could have made clearer so I thought I’d mutter about it a bit here. The short version is that herbivores spend a great deal of their time foraging for, and consuming, food. That puts them in the firing line of predators of course, but that’s going to be a major issue no matter what they do, and of course adults tend to be at a rather lower risk than do juveniles. As such, for something like a Triceratops or your average hadrosaur, having a large crest on the head is not likely to quite have such a major effect on their survival.

A predator however has a rather bigger issue. It’ll feed less often and unlike the average plant chewer, it’s prey can get out of the way and could see it coming. No matter your hunting style, the sooner potential prey sees you coming, the harder it’s going to be to grab it. As such, even a relatively small crest on your head might well be the end of your dinner if it’s seen, and of course the head is the one part any hunter would have to poke out of cover to see, hear or smell it’s targets.

In short, you’d expect theropods to have smaller crests than ornithischians becuase they have fundamentally different ecologies and are under rather different degrees of evolutionary pressure, even if the mechanism and origins (obviously here I’d suggesting sexual selection) are the same. And what is what you see, in proportion to the size of the animal, theropods crests tend to be quite small (Guanlong has the biggest one I can think of) but for the ornithischians, a crest that’s close to the size of the head it’s attached to is pretty normal. I’m not aware of anyone having commented on this size discrepancy before, but regardless of the drive for a crest, the ecological differences really would explain it quite simply.

Deinonychus

Hardly festive, but definitely awesome. A pair of mounted Deinonychus skulls from museums in China (above) and Japan (below).

Last Allosaurus, promise

Well, I’m on a roll, so here’s some photos of a cast of an Allosaurus skull held in Japan.

Another other Allosaurus

I’ve had this photo knocking around for a couple of years and never got around to using it. It’s an Allosaurus skull cast on display at the BSPG in Munich. However, with my recent post on the Carnegie Allosaurus, it seemed a good time to drag this out of the vaults and stick it on show. That’s it for today.

Twitter

Following an unfortunate / odd / distasteful / disturbing event earlier in the week, I’ve finally signed up to Twitter. I’m not expecting to do *too* much on there that’s not simply tweeting blog posts from the Musings and Pterosaur.net, but, well, you might well want to know. I’m sure there’ll be other bits and bobs on there of interest from time to time. You can find me under @Dave-Hone. See some of you there I suspect.

Taking photos of fossils in museums

As part of my huge and ongoing (but nearly finished) series of posts on material from the Carnegie museum, it was suggested in the comments that I write about the methods I use to take photos. I doubt there’s anything I can say that an experienced photographer can’t tell you already, but there are a couple of special issues that can come up and it’s something not everyone is likely used to dealing with. As such, I’ll run though it all and hope it helps a few people.

First off, the camera. I’ve always said you can take great shots with a cheap point-and-shoot and you can take terrible ones with a massively expensive SLR. That said it’s much easier to take great photos and harder to take bad ones with a good camera, so if you can afford to invest, it will make a big difference. Aside from that I don’t want to say much about cameras and lenses and settings as, well that’s part of good photography in general rather than taking photos of dinosaurs, but clearly if you want a good photo of the head of a sauropod or the details of a pterosaur strung from the ceiling, you need a good zoom and / or a macro lens. I take most of my stuff in dinosaur halls with about a 25 mm and then I have a 70-300mm zoom for details.

Next up, framing. Obviously how you frame your photo depends on what you want out at the other end, but there are some things to consider. First of all, line up the shot and check all around the edge of the frame that you have everything you want in place. Are all the feet in the bottom of the frame, the tip of the tail in there, the top of the head? Maybe the tail curves away and is hidden behind the body, so if you want it in there, you might have to move. If you want the photo to be of a specific element, consider taking the photo at an angle. For example if the head is angled down, then you’d naturally take a photo that showed that, but you can rotate the camera so the head runs straight left-to-right across the frame. The background may now look odd (beams or windows all crooked) but the bone is better illustrated. Try and make sure there are no people in the frame, or minimise where they are.

Don’t be afraid to adopt odd posture or lean out and round things to get the shot you want. Obviously be careful of your possessions and the material on display, but you can stretch an arm out over a balcony, or put the camera through a gap. A bit of practice and experience and you can get good shots even when you can’t see the viewfinder.

Be mindful of shadows and light. Your eyes adjust brilliantly to things that a camera won’t. Watch out for bright spots from reflections on glass or off metal supports, shafts of light from windows, or things being hidden in deep shadow. A lot of modern museums really like lots of small spotlights and these are great for eleminating odd shadows, but terrible for making bright spots on your photos. My technique is to alter the angle of the shot such that as many of these as possible are behind the bones, or *just* out of shot. Try enough positions and you should get the kind of shot you want with few, or even, none of these.

Try and avoid using the flash. Dinosaur mounts are a pain to clean and are often dusty, and the bones and mounts can be really quite shiny. A flash shot might get better illumination but it might be full of reflections and all the bones show up grey. So if possible, avoid it, and instead stick the ISO up on the camera and put the exposure time up. You can compensate with a tripod, or even just practice and a steady hand. Leaning on railings also helps keep things steady, or you can balance the camera on a bad or rolled-up jersey to get the shot you want.

In the case of cabinets, you might need to stick the flash on, so shoot at 45 degrees to the plane of the glass, or put the lens flush against the glass, both should stop flare. You can also use yourself to help block out reflections and make a nice dark area on the glass. Hold the camera with one hand (if you can) and use the other to block out spotlights behind you, drape a jersey off your arm, or even tie it around your thighs to hand between your calves. Little things like this can make a small difference and a few of them can add up.

Take lots of photos. With modern digital cameras you can take dozens and throw out loads of bad stuff. Even if it looks fine, take a couple again. If you’re not sure about things, take photos with different settings (flash on or off etc.) and at different ranges or angles. Taking things at subtly different angles can make nice pairs to show off details. If you have time, check some of them on your screen or even download them and check them on a laptop.

Take photos of signs. It’s nice and quick and can give a good reference for all manner of specimens and details. Try and shoot one specimen at a time so nothing is mixed up. Do sort your photos as soon as you can so you know exactly what close-up fits to which specimen.

Finally remember you can tweak things afterwards. You can always adjust tone, colour and exposure on the computer. You can rotate things a bit and crop out errors etc.

Right, that’s it from me, I hope this helps a few of you the next time you’re surrounded with dinosaurs on display.

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

Another Allosaurus


So having never covered Allosaurus before on the Musings in what, four years, I’ve now done in twice in the last few months. Last time out it was in Japan, but this is an all-American one that’s sat (to no-one’s surprise) in the Carengie. Well, more running than sat, but you get the point. Here it is alongside an Apatosaurus, though perhaps making its way towards junior.

This being the Carnegie, there’s also an original skull to accompany the mount and let you see real bone alongside the cast. Though as Tom Holtz has pointed out in the comments, it’s Marshosaurus and not Allosaurus.


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