Saturday 20 September 2014

The 'Spinosaurus reboot': sailing in stormy waters

UPDATE: 21/09/14: Following chats with Nizar Ibrahim and Simone Maganuco, it appears the Spinosaurus 2014 saga has another twist to take concerning the controversy over the revised hindlimb proportions. I'd rather write about it in a comprehensive fashion when I have the time (hopefully tomorrow) and am hoping to deliver some definitive, knock-out information from the authors which puts this controversy to bed. Bear this in mind before you read the following...

ANOTHER UPDATE: 22/09/2014: Read this.

Are depictions of Spinosaurus like this now redundant? Answer: who knows? After weeks of anticipation and teased images, the 'new look' Spinosaurus has met a sceptical reception from academics and the online palaeontology community, and they've not kept their opinions quiet.
One thing is clear a week after the 'Spinosaurus reboot' (a phrase coined by Mickey Mortimer) was revealed amidst a furore of academic and media swirl: Spinosaurus c. 2014 has not met the warmest reception from the palaeontological community. A sceptical tone, sometimes very openly so, can be seen in numerous articles from the first popular science write-ups to articles penned by professional palaeontologists. As we all know by now, the primary concerns centre around Ibrahim et al.'s (2014) new Spinosaurus aegyptiacus reconstruction, which Brian Switek describes as a 'hodgepodge [of] different dinosaurs... the new subadult skeleton, digital representations of the original and long-lost Spinosaurus bones, vertebrae and hands that may or may not belong to Spinosaurus, as well as replacement parts from an assortment of spinosaurs'. Allegations have been made that scaling errors are responsible for the unusual new bauplan rather than an unprecedented lifestyle, with the allegedly tiny legs being far more proportionate once the scaling problem is addressed. These undermine the credibility of the furthest reaching claims of the authors - theropod quadrupedality and a lifestyle/locomotory strategy akin to early whales. Two widely shared and commented blog articles on this topic over at Scott Hartman's Skeletaldrawing.com have cast enough doubt over the new reconstruction that the Spinosaurus 2014 authors publicly responded to the criticism, but the reply is really just a holding message. Other than pointing out well known problems of measuring images rather than fossils (which, to be honest, are unlikely to produce the large scaling problems levelled at the paper), the message is essentially 'all will be clear in an upcoming Spinosaurus monograph'*.

*For what it's worth, I took five minutes to measure up the new Spinosaurus skeletal restoration myself following Nizar Ibrahim's measuring instructions for dorsal vertebra 8, just to see if I could make head-or-tail of the debate. Differences in measuring landmarks were chalked up as being a potential problem, so I measured the ilium and femur blind to other methods, instead using whatever landmarks were most intuitive. For both the ilium and femur lengths, I arrived at almost identical scaling errors to Scott, and the legs should - according to the data in the paper - be c. 25-27% larger in the reconstruction. Something - the original measurements of the specimen or the reconstruction - just doesn't add up, and I suspect the latter, as I figure someone would have owned up to and corrected simple numerical errors in the paper by now. My working is below.

Independent test of the alleged hindlimb proportion issues in the new-look Spinosaurus. Skeletal reconstruction from Ibrahim et al. (2014); see Skeletaldrawing.com for the posts inspiring this test, especially this and this.
The controversy extends much further than just scaling, however. Across other articles, multiple issues have been raised including the incorporation of isolated spinosaur elements and other taxa to a single Spinosaurus reconstruction; whether all the material used in the reconstruction is of spinosaurid origin (e.g. this humerus); the likelihood for theropod quadrupedality (remember that we don't know anything concrete about Spinosaurus forelimbs: there is really nothing to suggest quadrupedality in this animal other than its alleged proportions); the authors taking too much credit for the 'semi-aquatic hypothesis'; the suitability of their journal choice and the somewhat ambiguous circumstances surrounding the provenance of the new material. And this is to say nothing of the extensive discussion on social media, much of which revolves around the same topics. This is not to say the Internet is hating on Ibrahim et al. (2014) - I think the pieces linked to here are balanced, reasoned critiques, not slanderous attacks - and, before anyone asks, I'm not saying I agree with, or even have opinions on a lot of these issues. The point here is that the 'Spinosaurus reboot' has experienced a very bumpy, almost slightly hostile landing.

The response to the Spinosaurus reboot is of some interest. Controversial, questionably-supported claims are made in palaeontology all the time, but they don't get the online palaeontology community anywhere near as riled as Spinosaurus has in the last seven days. Ibrahim et al. (2014) clearly hit a nerve, perhaps because they have inadvertently created a 'perfect storm' for scientific backlash.

At the heart of the storm is a data vacuum about Spinosaurus - an odd state to be in seeing as we're now meant to have a good idea what it looked like. The main discussion about Spinosaurus in the last week has been methodological: that is, trying to figure out how the new reconstruction has been put together. This is because the paper lacks essential details concerning how the 'hodgepodge' of spinosaur bits were scaled to size or identified as Spinosaurus aegyptiacus in the first place. In skipping these details readers are left guessing - and discussing - how the proportions were ascertained and whether they are trustworthy. That people would want to know this was predictable: you can't propose a radical notion like a famous theropod being a semi-aquatic quadruped, even converging on whale ancestors, without academics, enthusiasts and dinosaur nerds wanting to know more. While the paper does have plenty of good data, it lacks transparent methods and discussions where it counts, leading readers to make their own tests and discoveries. Lest we forget, people like talking about dinosaurs online at technical levels, and it's only natural that blogging software and social media is being fired up to discuss these revelations. It's quite likely that there'd be less fuss made if the paper stood on sounder methodological ground but, ultimately, controversy sells, in part because the continual uncovering of new information and scientific debate makes for good copy.

Compounding this effect is the star of the show: Spinosaurus itself. By now, Spinosaurus has to be one of the most popular dinosaurs of all. It's the one widely known theropod to have a size advantage over Tyrannosaurus, has starred in a couple of big movies and documentaries, is undeniably cool looking, is a bit 'alternative' as dinosaurs go... for lots of reasons, it's a major dinosaur celebrity. Even among po-faced academics, the sheer size and unusual anatomy of Spinosaurs means most - probably even guys who work on brachiopods - find it a little bit more interesting than usual. Any publication on this animal is guaranteed a good amount of casual interest, but one where the animal is almost completely reinvented will send the online palaeontology community into overdrive. Did anyone else have to wait for the Science website to stop crashing when the embargo was lifted last week? I'd be interested to see how riled the internet palaeontology community got if someone questionably reconstructed a small ornithischian. For contrast, consider that the publication of another dinosaur with a radical lifestyle - the burrowing dinosaur Oryctodromeus - ruffled relatively few feathers when it was published, despite it's PR. I remember most discussion of it on the Dinosaur Mailing List concerning the formulation of its name.

Driving the storm is the considerable hype surrounding the paper, which bears little resemblance to traditional scientific press releases and is more akin to the launch of a summer blockbuster. 'Surrounding' is the right word, too, as tantalising glimpses of the new reconstruction were online weeks before the paper's release, foreshadowing the avalanche of 'official' art, articles, and videos which would follow. There are documentaries, a tie-in exhibition in Washington DC, press conferences and lectures. You'd think Spinosaurus and its wranglers were rock stars. I mean, can you name one other palaeontological PR event which needs dry ice?

The popular side of this release has been a resounding success, which - whatever you think of science being spun as a media event of this kind - is certainly well earned. In concert with National Geographic, Ibrahim et al. (2014) have put on a very slick, professional show with some wonderful art and graphics, and they've certainly made it difficult to miss. But publicity can be polarising, not to mention difficult to steer. It seems the PR for Spinosaurus 2014 has somewhat backfired in the palaeoblogosphere, the conspicuous, sensational nature of the story encouraging interested minds to investigate and test, and ultimately question the findings at the core of the hype. I expect the extensive publicity surrounding a widely-questioned paper also brings a faint sense of irritation to some, prompting them to advertise the fact that the conclusions are not as watertight as the documentaries, exhibition and magazine covers indicate. Whereas other studies with problematic conclusions would slip away into the literature to be discussed within the closed confines of scientific journals, Spinosaurus 2014 cannot hide easily: the advertising and publicity for this paper is keeping the controversy relevant and prompting more responses. I do wonder what National Geographic, presumably footing the bill for all this press work, are making of the frosty scientific response to Spinosaurus 2014.

Between the data vacuum of a radical new proposal, a megastar fossil animal and persistent reminders of a controversial study, it's hardly surprising that the online palaeo community has spent the week giving the Spinosaurus reboot a good grilling. What does the future hold? With the promise of a Spinosaurus monograph, we can be sure that there will be more discussion eventually, but, more realistically, the next major ripples will follow response papers. Some authors are already in talks about this and - given what's been demonstrated online already - there are strong cases to be made against the main hypothesis of the Spinosaurus reboot. Is a rebuttal article appropriate with another paper on the way? Yes, entirely, because we have to work with data which is available and test the hypotheses presented to us. In this case, the new-look Spinosaurus and the many implications made about its habits have been quickly questioned - deemed irreproducible, even - by a number of scientists, and this should be 'formalised' as a genuine concern about the initial paper. The upshot, of course, is that the eventual monograph will have to take this into account, which should make for a stronger publication, and hopefully an improved understanding of Spinosaurus itself.

I can't help think that there are a few causalities from the last week, not least being the good new data in Ibrahim et al. (2014), such as Spinosaurus weirdly tetradactyl feet, unusually short femur and dense bones (Ibrahim et al. 2014). What do these mean, in light of the hindlimb scaling controversy? Is the long first toe more to do with spreading weight than creating a flipper? Are the thickened bone walls more to do with relocating the centre of gravity than swimming? There are interesting discussions to be had there, but they've been overshadowed by other details. Also, scaling issues or not, I imagine the 'dachshund' Spinosaurus is here to stay for a while, so we can look forward to having to downplay confidence about the new reconstruction of Spinosaurus for the foreseeable future. It's very doubtful that the press will be interested in a story about the uncertainty over a new paper, nor is National Geographic likely to replace the legs on its Spinosaurus model with question marks. This is a constant bugbear of working within science of course: the media is interested in new and exciting discoveries, but has virtually zero attention span for scientific debate.

Finally, is there anything to learn from this? For me, the message is that while publicity is largely about presenting conclusions and results, we can't just assume our audiences are passive. Particularly if you're discussing a fan-favourite species (and let's face it, 'fans' here includes a good number of vertebrate palaeontologists), people remain just as interested in what you've done as what you conclude, and omitting those details leaves papers, and those associated with them, vulnerable to misunderstandings and criticism. As demonstrated this week, even the combined might of Spinosaurus and its PR campaign is not immune to this: when the world's largest theropod took a bite out of the Internet, it was bitten right back.

Reference


  • Ibrahim, N., Sereno, P. C., Dal Sasso, C., Maganuco, S., Fabbri, M., Martill, D. M., Zouhri, S. Myhrvold, N. & Iurino, D. A. (2014). Semiaquatic adaptations in a giant predatory dinosaur. Science, 1258750.

14 comments:

  1. Really we won't know how good or bad the reconstruction is until that monograph. There's also the fact that we're working off one good specimen. Best we keep looking for some more of them, if we want more clarification.

    I'll be the first to say "In the absence of proper data, speculate wildly.".

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  2. Hi Mark congrats on the wedding I hope you have more planned for your honeymoon than "spinogate". I like many of your observations on the spino-roll out. It should be noted that there is really no way that this rollout could have been modest... that being said I believe that, hindsight 20/20 Ibrahim et al., releasing the monograph and paper concurrently would have had much benefit. We can all speculate that with all the parties involved nat geo/smithsonian etc etc/time constraints and getting that museum stuff up and running would have some benefit to be opened before the holidays $$... and Sereno has shown us before he is a master showman.

    That being said the reason(s) I am attaching my wagon to the conclusions of Ibrahim et al. are as follows:

    1) There are two independently arrived at skeletal reconstructions that converge on the same body plan. Image 1 Ibrahim 2014
    Image 2 Marco Auditore

    As both parties had access to the bones/and measurements first hand I am going to give value to these measurements over the objections given due to scaling issues noticed by Hartman. No offense to Hartman, I respect him a lot, but there are vagaries that can be due to choices of landmark/loss of three dimensional bowing of the femur not captured on a flat screen. Long story short until these proportions are demonstrably and unequivocally shown to be false I am attaching my wagon to the 8 author published peer reviewed paper. You can choose not to or remain agnostic I think all three options are tenable positions to take at this point.

    2) A certain blogger/researcher/paleontologist, who shall not be named but who I am sure you can all figure out, who happens to share statehood with several of the authors and been privy to the bones and direct questioning of the authors - this person has taken more or less an "agnostic" position (but I feel knows more than he lets on) has not spoke as stridently in objection of the material to the extent of other workers. I will leave it at that.

    3) I believe the suite of features described in the new paper; retracted nares; heavy thick bones (limb and dorsal spines btw); obvious and striking hindlimb reduction coupled with strong attachment site for caudemofemoralis muscle (inferred underwater running); sensory snout; gaff like hand claws/croc like snout; flexible and supple tail; tetradactyl paddle like hindfeet; and environment dominated by water with abundance of potential large aquatic prey - I believe this preponderance of evidence satisfies an increasingly aquatic adaptation in this animal. Of course this might not be enough evidence for you and that's ok.

    For those who are on board with an increasingly aquatic adaptation in S.aegyptiacus you might find this post Spinosaurus: The Tidal Rover (aka How I Interpret the Sail) of interest or my hypothesis on belly sliding as a viable form of locomotion is S.aegyptiacus Did Bakker Get Spinosaurus Right After All?

    In conclusion agnostic/in support of/ or doubtful of the conclusions are all tenable positions to take at this point and how far you want to go down the wormhole of "what was Spinosaurus like" depends a lot on where you fall on this spectrum.

    Duane Nash antediluvian salad



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    1. I haven't noticed any consideration in this belly-sliding hypothesis (and I perused your blog post on this) of the much greater mass of at least adult spinosaurus and of the shape of the spinosaurus torso. Even the largest salties are small compared to modest estimates of spinosaurus mass. Crocodiles also have a broader, flatter torso than even the NatGeo reconstructions of Spinosaurus. Mass and shape have a lot to say about whether an object propelled across a soft surface will plane over the top of it or plough through it.

      As to the sail as helping the animal to move with the tides, apart from its image of Spinosaurus floating along sidewise, there's that it is entirely unnecessary. Water is a denser medium than air, denser, of course, than Spinosaurus, and more viscous than air, so there's no need for additional surface to allow currents to get a grip on an object to get them moving along. Unlike sail boats or portuguese man of war, your Spinosaurus drifting with the current is moving along with the water, not trying to move across the water faster than, across or even against the current. If you want an analogue for your drifting Spinosaurus, look to balloons, which are similarly buoyed up in their similar density medium and don't seem to need any sails to get them moving with the air currents.



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    2. Very valid criticisms thanks Mike.

      With regards to shape/mass of spino operating as belly slider: I think we will see more than one method of locomotion possible and perhaps probable especially through the different ontogonies of this undeniably massive animal. My main point/contention is this: a crocodile can and does use multiple terrestrial locomotions but they tend to discriminate on what substrate they do it on. Highwalking more on stable ground/semi-sprawled on dry-semi firm substrates/belly crawling/sliding on extremely muddy, unstable grounds. I think of the debated options belly sliding offers some advantage on especially muddy (i.e. tidal mud) substrates. It at least has as much "steady ground" as the other two hypotheses of obligate/quadruped. Additionally soft tissue and gastralia - do we even have any gastralia for spino? - can give a lot more info than we currently have with regards to the shape of the ventral surface.

      Interesting points about the sail underwater. I still would suggest that with a bone density higher than alligators/penguins it would sit low in the water. All options of sail out or in or a mix are positions that can be taken. But I think it worthwhile to explore what a sail underwater could be used for. I do think it also worthwhile to look into where the body would naturally float at when the eyes and nose were above water (like crocs/frogs/seals/beavers).

      Perhaps underwater the sail could offer better control of the direction it was drifting in? As I argued on my post there are in fact lots of times when you do not want to be seen - esp as a young one growing up ( I am admittedly inferring high levels of intraspecific aggression/cannibalism).

      But honestly thanks for taking the time to write that good points.

      Duane Nash antediluvian salad

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  3. Quick question: Have any of the post publication complaints about the original publication come from anyone who has directly measured the materials or high quality casts of the materials, or is this all from photos and reconstructions? If only the latter, then somebody's gotta get themselves on an airplane and don't forget the calipers, because it is at least in my corner of paleo a bit unprofessional to question the legitimacy of research as though you've reproduced it when you haven't actually reproduced it.

    Not to say the questions cant be raised as questions but I'm seeing strongly worded alternative reconstructions being proposed and I just want to know if any of that is based on original materials. I'm thinking not from what I've read.

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    1. "I'm seeing strongly worded alternative reconstructions being proposed and I just want to know if any of that is based on original materials."

      The problem is that that question can, because of the discrepancy between the published reconstruction and the published dimensions, be asked of the quadrupedal Spinosaurus reconstruction.

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  4. By the way, loved your book, and my review of it is getting a gazillion page views; pterosaurs are cool, apparently!

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    1. Thanks for the comments Greg, especially about the book. Glad you enjoyed it.

      "somebody's gotta get themselves on an airplane and don't forget the calipers, because it is at least in my corner of paleo a bit unprofessional to question the legitimacy of research as though you've reproduced it when you haven't actually reproduced it."

      I think you're confusing two issues here. The test labelled at Spinosaurus 2014 by Scott Hartman, then replicated by myself, is checking the data consistency of the Spinosaurus paper, not attempting to produce an independent reconstruction of Spinosaurus. The issues identified by Scott may have called up grounds to check out the original material again, but this is not a requirement of simply checking whether all the data presented in the paper points to the same answer. In this respect, folks like Scott and myself are not being unprofessional: we're testing a novel hypothesis using the data meant to support it. That isn't unprofessional: that's science.

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    2. Are you measuring the published reconstruction? But what about foreshortening in a flat picture of limb bones placed at an angle?

      Matt Baen

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  5. Crocodilians and anhingas spend a great deal of time basking after foraging as they lose their heat to the aquatic environment, could spino's sail have acted as a collector for solar radiation offsetting heat lost to the water potentially increasing available foraging time?

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  6. When talking the possibility of quadrupedality in theropods, I think it's worth mentioning that pronation (the main reason quadruped theropods are believed to be almost impossible) is no problem as long as the creature stays underwater with the hands not having to bear as much weight as would be needed on land. In fact, I'm of the idea that spinosaurids moved through shallow water by pulling themselves forward with their large thumb claws anchored in the riverbed (because I really believe them useless in predation, they make much more sense as an aid in locomotion to me). A species of spinosaurid that has reduced hindlimbs and enlarged forelimbs to the point of apparent quadrupedality would support that idea well imho.

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  7. Pronation itself is not a problem, given that NO dinosaurs pronate their hands, including quadrupedal ornithischians and sauropodomorphs (there's a sort of online myth that theropods are the only dinosaurs unable to pronate hands). What makes not plausible a quadrupedal theropods is the absence of quadrupedal adaptations in the shoulder girdle, antebrachium and carpals (all features currently unknown in Spinosaurus, and thus, pending new data, assumed to be as in other theriopods).

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  8. Hi Mark!
    I greatly enjoy reading your blog on a regular basis, and know quite a few people that do as well. Thank you so much for keeping us folks more educated about dinos.
    I have a question regarding the habitat of spinosaurus that I would like to ask you. As I understand, from the kinds of deposits spino bones are found, it is sugested these guys lived in a mangrove type of habitat. They refer a type of halophyte fern as the most common plant in the habitat. Do you know if the remains of other types of plants were found in the same deposits? Like large trees or something that could be similar to the true mangroves we have todaY?

    Cheers

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