Archive for July, 2013

More outreach and communications

So once more I’ve been doing outreachy stuff that’s not just the Musings and so want to spread the word on the off-chance that some of my readers will want still more Hone-generated ramblings.

First off, The Lost Worlds over at the Guardian still keeps on going and I’m still posting material there regularly. However, they have just updated their name and so any old links may no longer work and so you’ll be wanting to use this link now and update any you have on your own blogs etc.

Second, I recently did an interview for the Jersey Boys Hunts Dinosaurs site, talking about my research and the advice for students and young researchers hoping to break into palaeo.

Finally, I recently sat down the people from Faculti Media. This is an interesting new concept where they create short videos of researchers talking about their work to provide a platform for outreach. It was great fun to do (but tricky, although edited, it was close to being live with only a couple of takes at the thing) and I think it offers a new approach with nice little bite-sized chunks of science explained by the researchers. In my case, it was on sexual selection and socio-sexual signaling in dinosaurs and it’s come out quite well, (though clearly the camera was focused on the background, not me, whoops!).


An appeal for data on dinosaur tail data

Regular readers should be familiar with my 2012 paper on the lengths of tails in non-avian dinosaurs (those who you who missed it, for shame! can catch up with my post here). In this I looked at the general lack of complete tails in the fossil record, but also showed that tail length varies considerably in dinosaurs, and thus should not be included in length estimates or mass estimates derived from length.Collecting data for the paper I scoured a number of museum collections, went through as much of the dinosaur literature as I felt able, and also contacted numerous researchers and curators to ask for any ideas and things I might have missed or undescribed specimens hidden in basements and drawers. Many people were generous with their time and knowledge and by the end of it, I was really pleased with what I had in terms of a dataset.

Almost inevitably though, without hours of publication and my blog post on the subject, people started contacting me with new leads. Many were things I had looked at and decided were not complete, but some were things I had missed and represented additional data. Great though this was, there was not a lot I could do with even a handful of new data – the paper was done. However, inspired I did dive back into the literature and had another look and did find a few more and as you may have guessed, have now got as far as I, or rather we, can. This time out I’m collaborating with Scott Persons (who has been doing a lot of his own tails stuff) and a mathematically inclined colleague Steve Le Comber.

Scott and I have pooled our resources and have now found nearly 50 dinosaur specimens with complete tails, though we have this time out also been including specimens with ‘nearly’ complete tails. Obviously subjective, but we’re working on that.

Anyway, we’re appealing for more data. If you are aware of a dinosaur that has a truly complete (every single caudal vert, down to the last nub) tail, that’s not on the list, then do please let us know. If you know of something that’s near complete (maybe just a tip missing, or a couple in the middle or similar) do also let us know. Please be as specific as possible – “I think I saw a hadrosaur with a good tail in the AMNH” isn’t going to win you any prizes or get us anywhere, and we have at this point checked out a lot of material. On that note, all we can really offer is a mention in the acknowledgements for good leads that yield datapoints, and this may also include some limited measure of gratitude, or even a pint at the next conference where you catch us. Maybe.

Here are the lists of what we have to date.

Complete tails:

Othneilosaurus SMA 0010
Jeholosaurus IVPP V 12529
Scleidosaurus NHM R1111
Scutellosaurus MNA PI. 175
“Saichania” MPC 100/1305
Pinacosaurus PIN 614
Dyoplosaurus Arbour et al., 2009
Dryosaurus YPM 1884
Tethyshadros Dalla Vecchia, 2009
Edmontosaurus Lull and Wright, 1942
Lambeosaurus ROM 1218
Corythosaurus ROM 845
Hadrosauridae indet TMP 1998.58.01
Centrosaurus Brown, 1917
Psittacosaurus Sereno, 1987
Psittacosaurus IVPP V 120888
Coelophysis AMNH 7229
Sinocalliopteryx JMP-V-05-8-01
Gorgosaurus Currie, 2003
Gallimimus Osmólska et al., 1972
Ornithomimus TMP 1995.11.001
Caudipteryx IVPP V 12430
Nomingia Barsbold et al., 2000
Microraptor IVPP V 13352
Mei Xu and Norell, 2004
Jinfengopteryx CAGS IG 040801
Archaeopteryx Wellnhofer, 1974
Epidexipteryx IVPP V 15471
Lufengosaurus Young, 1941
Camarasaurus Gilmore, 1925
Opisthocoelicaudia Borsuk-Bialynicka, 1977
Protoceratops Fastovsky et al. 2012
Protoceratops Fastovsky et al. 2012
Leaellynasaura Herne pers comm
Chasmosaurine Mallon, 2010
Stegosaurus SMA 0092
Archaeoceratops IVPP V11115
Parksosaurus ROM 804
Anchiceratops CMN 8547
Microraptor Li et al 2012
Anchiornis IVPP
Sinusonasus Xu & Wang 2004
Spinophorosaurus Remes et al 2009
Kentrosaurus Holotype
Ornithomimid TMP 90.26.01
Tenontosaurus OMNH data

Near complete tails:

Epidendrosaurus IVPP V 12653
Sinornithoides IVPP V9612
Ceratosaurus USNM 4735
Khaan IGM 100/1127
Corythosaurus Lull & Wright, AMNH 5240
Anatosaurus Lull & Wright 8399
Anatosaurus lull & wright
Tianyuraptor Zheng et al 2009
Apatosaurus Gilmore 1936
Juravenator Chiappe & Goehlich, 2010
Sciurumimus Rauhut et al 2012
Psittacosaurus sinensis IVPP V 738
Psittacosaurus IVPP V14341.1
Psittacosaurus IVPP V14341.2
Psittacosaurus IVPP V14341.3
Psittacosaurus IVPP V14341.4
Sinocalliopteryx Ji et al 3007
Sinosauropteryx Currie & Chen 2001
?Heterodontosaurus MCZ 4188

Any other suggestions (specimens or papers), please do add them to the comments below. All help is most gratefully received.

Nasutoceratops art

Well the new ceratopsian Nasutoceratops has been named and the paper is out. If you want to read a bit about it, I have a post up over on the Guardian here. Since that’s already written, I wanted to do something a bit different here and thanks to Mark Loewen, I’ve been supplied with a series of nice images and art of the beastie and it’d be a shame not to use them here.

Nasutoceratops skeletal drawing by Lukas Panzarin
Here’s Lukas Panzarin’s skeletal of the animal (note that most of the skull is known).

Nasutoceratops stipples by Sammantha Zimmerman
Here’s Samantha Zimmerman’s lovely scientific illustration of the skull in two views which really shows off the shape and pattern of the horns well.

Nasutoceratops titusi on black by Lukas Panzarin
Lukas Panzarin is back again with this life reconstruction of the head.

Nasutoceratops titusi by Raul Martin 300 dpi
Next we have a Raul Martin piece of the whole animal, making its way through a swamp.

Nasutoceratops titusi by Andrey Atuchin
And finally Andrey Atuchin’s effort, another life reconstruction, this time with a nice tyrannosaur half hidden in the background.

All in all some beautiful stuff, but I had no room for it on the Lost Worlds, so I’m pleased to get it up somewhere. Thanks to the team for sharing and great stuff from all the artists.

Science communication and fossil preparation

As part of my travel to Canada for the Project Daspletosaurus work, I attended the Fossil Collections and Preparation Symposium hosted at the Tyrrell. Obviously I’m not much of a preparator, but after getting through the mammoth Gorgosaurus prep stuff with Darren Tanke, there was obvious scope to talk about sci comms in general and what we’d done with the field of preparation specifically and how me might go about improving that. All of the talks were recorded and have now gone up on line. There’s some cool stuff like removing old consolidants  or microvertebrate screening, so hunt around on the Tyrrell’s YouTube channel, so it’s well worth having a look around, there were a ton of talks.

Species recognition in dinosaurs? Not so much

Those with an interest in dinosaur cranial crests and exaggerated structures (which should really be everyone since they turn up in pretty much every major lineage one way or the other) will probably be aware of the exchanges going on in the literature over these features. Although myself and colleagues have been advocating that sexual selection (and or socio-sexual signaling: the two can be hard to separate) is a likely strong candidate as the prime driver for many of these features, others have been advocating that this is not the case and instead the answer lies in species recognition. The latest to delve into this area is a paper I’ve done with Darren Naish and is the first time we’ve addressed this issue directly. While we have written or contributed to a number of efforts looking at support for sexual selection in dinosaurs, this is the first time we have tackled the other side of the problem.

The paper originally started as a long section that was included in our paper on mutual sexual selection with Innes Cuthill, but as we were later forced to cut down the length of the submission, this was a section that was relatively easy to prune as tangential to the main issue. However, we felt it needed saying and with new data coming out and the discussion ramping up, we revived and revised the work and it is now out. (Well, it has been in press and available for a while but is now properly out).

This is an important area for discussion – after all, the horns, crests, frills, plates, bosses and the rest (not least feathers) are key features and adaptations in various dinosaur lineages and trying to work out how they might have been used and what this means for evolutionary drivers and patterns is going to be a major issue. It’s hard to really understand stegosaurs or ceratopsians say if you can’t say that much with confidence about their ‘bonus’ features. While obviously each clade, or even each genus / species probably needs to be taken on a case-by-case basis when it comes to detailed analyses, some gross patterns can be seen or at least discussed. In the case of species recognition, is it even an actual ‘thing’ when it comes to exaggerated structures, and if it is, how is it supposed to work. The hypothesis has enjoyed some support in the literature for some unusual dinosaur features so it’s well worth examining.

Species recognition (in the context of exaggerated structures) for those who don’t know, is the idea that individuals of a species use these features to help them recognise cospecifics with to ensure they mate with the right species, or to maintain herd coherence. In short, carry round a key feature and you should be able to make it easier to stay in touch with the right animals and avoid the wrong ones. Various lines have been put forward to support this idea (in general and specifically towards dinosaurs) but we feel that none of them actually stack up and some have some serious problems.

First off is a pretty big issue – to our knowledge there is no evidence of any living species using some form of crest or exaggerated structure for species recognition. Individuals of species do recognise each other (not a big shock) but actually things like antlers or casques don’t seem to form part of the pattern that conspsecifics recognise. This may not be a big shock, after all, you can recognise a species by the overall appearance (size, shape, colour), their smell or specific sounds they make, behaviour, and other features. On top of this, some species are very varied in appearance for the big features (antlers of deer look very different as they grow, and are different between males and females and between juveniles and adults etc.) so relying on one feature is a bad idea at best, and a plastic one an especially bad call.

Plus of course, you often get closely related taxa that are sympatric. Is some big set of horns going to help you correctly identify conspecifics if there are half a dozen similarly-looking species also in the area? Look at things like African antelope and gazelle, or more extreme examples like tyrant flycatchers. We have trouble telling them apart sometimes based on their morphology, yet they seem to have no trouble. If this is so critical to dinosaurs, why to the iguanodonts seem relatively free of crests, but the hadrosaurs go nuts with them? And why are they all so similar in general form between species when they are supposed to help separate them out? Surely they should be divergent, not all similar in appearance. And why do we see things like Wuerhosaurus or Spinosaurus running around with all this weight to make sure they don’t mate with the wrong species when there are no other members of their clade to get confused with?

In some cases we see both issues coming together. If we look at the various small protoceratopsians of China / Mongolia, we see disagreement between researchers as to how many species (or genera) there may be. What is notable however, is that the characters being used to separate them out don’t typically involve the frill or bosses of the skull, and where they do, may be things that are not externally visible (e.g. the width of the media bar in the frill). In short – if there are multiple species here, the frills are apparently similar enough that we can’t separate them and so are unlikely to be part of the identity concept of the animals. If however, there is only one species present, then we are back to the paradox of a large frill being carried around but with no other species that could confound any signals.

On top of that, is it really worth it? After all, while you do want to stay in touch and make sure you mate with the right species, bolting on a good few kilos of bone to your head, and then the extra muscle to support it, and then lugging that around for your entire life is a lot of effort. When you can probably already identify conspecifics by their colour, patterns, scent and calls (of simply because nothing else like them at all is on the same continent) surely these would experience strong negative selective pressures if they didn’t have any other support.

Furthermore, how would such features ever evolve? If the populations / species were allopatric then we return to the situation of them not having another group to get confused with and crests are unnecessary for recognition. If they were sympatric though, how would this work? Pretty much the definition of a natural biological population is one that is breeding within itself, but here we’d have to have a population diverging because some don’t recognise each other as conspecifics even though we would expect, pretty much by definition, there not to be too much difference in structure shape between them (e.g. a tiny crest vs no crest). Now some animals might prefer each other, but that’s mate choice, not recognition, and there would have to be enough individuals for this to work – one mutant with a crest when no one else has one is not going to start forming a new species, and if there were a bunch of the with the new crest they’d also have to identify each other as different and avoid mating or hanging around with the others. So how would a large feature that’s for correct recognition allow a population to split in this way? To us at least it appears most unlikely to occur at all, let alone repeatedly.

In addition to this, there is rampant hybridization of closely related species in the natural world (and indeed in captivity). Even extravagantly ornamented species like pheasants with numerous adornments and bright colours and patterns hybridise regularly – clearly no matter how extreme the cue, at least some animals regularly have problems with them or are indiscriminate, but either way they are not that effective.

While some data like the apparent rapid growth of structures late in ontogeny has been used to support the idea that they are characteristics involved in socio-sexual signaling, it’s also a problem for the herd coherency part of the model. After all, lots of juvenile dinosaurs are known from aggregations suggesting they spent a lot of time together, even when the adults did not appear to. If these features were key, we’d expect juveniles to have them, and adult perhaps to shun them when they were no longer needed, but instead the opposite is true. In general the herd coherency argument is a bit odd anyway, again you have lots of ways of identifying and keeping in touch with conspecifics and some are clearly better than visual aids. Scent can have a temporal component, and vocalizations can be interactive beyond line of sight (especially useful in forests, or when things are behind you, or you are foraging and looking down etc.). No matter how big they are, visual structures are not always going to be that useful, even if they are unique.

In the increasingly infamous issue of Torosaurus and Triceratops, if these animals are truly conspecific then for a start we are back to the issue of ‘lone’ taxa (I don’t think Leptoceratops is going to be much of an issue here) and the pointlessness of crests where none are needed. On the other hand, this is also potentially a problem for the mate recognition idea. We know that at least some dinosaurs were sexually mature before they were osteologically mature and this could be the case for these animals too. If so, then the alleged transformation between one morph and the other would create confusion – both the Triceratops morph and the Torosaurus morph (or indeed anything in between) would be viable mates.

In short, we really have no clear evidence for species recognition in any living species, and that alone should make it unlikely to have been a key player across dinosaurs for the whole Mesozoic. Such structures would be costly, and yet not necessarily do the job it is supposed to with other signals being cheaper and just as effective, or more effective in many circumstances. It’s not clear why it should be so important for some clades and not other similar forms (iguanodotids vs hadrosaurs for example) and is clearly either redundant for some taxa, or would not actually reduce confusion. Nor is it clear quite how this would evolve in the first place, or why it would be sustained, and hybridization suggests that crests alone would not even prevent incorrect matings. Put this all together and we feel that there really is no good support for the idea of crests and other structures being primarily used in species recognition. They did of course likely have an effect – it would be odd if Stegosaurus or Corythosaurus didn’t use their respective features as part of how they identified one another. But that does not make them the prime, or only, driving force of all these different features in all these different lineages.

There was a fashion in dinosaur palaeo to write off any odd structure as simply sexual selection and leave it there. This was rightly railed against, but what was often criticised was the fact that sexual selection seemed undiagnosable in the fossil record and so the problem was that it was untestable rather than the fact that such throwaway remarks devoid of context or explanation do little for the subject. Now we are in the odd position where rarely you see very similar comments (in terms of their style) about species recognition popping up in the literature about exaggerated structures despite the lack of support for it, and the now (well, we think), strong cases made for sexual selection, or at least it’s assessment. Although previously the case for sexual selection was pretty weak, it is at least an extremely common phenomenon in living taxa and with obvious powerful effects on anatomy and behaviour. Species recognition has not yet even been shown (in relation to exaggerated structures) in any living clade, and while offhand one-line explanations are not the way to go, it seems odd that one has been replaced with the other.


Hone, D.W.E., & Naish, D. 2013. The ‘species recognition hypothesis’ does not explain the presence and evolution of exaggerated structures in non-avialan dinosaurs. Journal of Zoology, 290: 172-180.

Another incredible Gorgosaurus


Gorgosaurus has had a lot of love on here thanks to the huge series of posts on the preparation of a specimen by Darren Tanke, but also with this recent effort. Despite the awesome quality of those, this one is arguably better. While not complete (almost no tail dang it) and with a little bit of squishing to the skull, this one clearly retains an awful lot of the 3D relationships between bones and it overall rather uncrushed. This is a rarity to say the least and really helps show just how, well, big these things were. As you can see from the images, the animal is really barrel-chested and chunky. Obviously restoring muscles and fat layers etc. is another issue entirely, but I think it’s fair to say that this animal should really not be slim.

Obviously there’s a ton of just beautiful detail here and some lovely nuances (like the interlocking gastralia, the massively retracted left leg, the ilia tight to the neural spines of the sacrum, and the rugosities on the snout). It may not have quite the visual impact of the last one, but there’s really a lot to be gained from this and palaeoartists out there should be (t0 quote a friend of mine) onto this like a starving chihuahua on a pork chop.





Near perfection with Gorgosaurus


This is the famous Gorgosaurus specimen at the Tyrrell that is pretty much perfection when it comes to tyrannosaurs. It’s as complete a skeleton as you are every likely to see, in wonderful condition, articulated pretty much perfectly and in an iconic posture. I loved simply looking at it, and it’s a hell of a thing.

I did not however love taking a photo of it, the position it has been put it, combined with the lighting in the hall makes it extremely hard to photograph. Now while museums can’t cater to the requirements or demands of every single visitor (some want it light, some dark, some want things high up, others low down, some want chairs, some want spaces etc.) it is frustrating that what is possibly their best specimen on display is annoyingly hard to photograph and hence this single decent shot which really doesn’t show off the feet properly, or indeed the complete (yes, actually really complete) tail.

Even so, it’s a magnificent specimen and I think the photo does it a decent amount of justice and at least lets you see the real quality of the preservation and indeed the preparation to get it out like this. Enjoy.

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