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Tonight is the debut of the ballyhooed BBC1 programme “Attenborough and the Giant Dinosaur“, featuring Sir David and The Titanosaur-With-No-Name, at 6:30pm. Furthermore, this week I presided over a showing of “T. rex Autopsy” to our RVC undergrad Zoological Society, with a very enjoyable Q&A afterwards. So it seemed timely for me to do a post about a theme that links these two documentaries that I helped with, my own research, and science communication and palaeontological research more generally. But first let’s get this out of the way:

It was great.

It was great. I could gush more but that’s not what this post is about.

Stomach-Churning Rating: ~7/10; mainly the elephant leg dissection that’s not far below, which is a bit messy.

For the titanosaur documentary with Sir David, and the incomparable Ben Garrod as well, we had an old elephant “friend” of mine (subject of many biomechanics studies we’d done) walk across a pressure pad to demonstrate how the elephant locomotion works and some of the basic similarities with how a giant sauropod dinosaur might walk:

A broader feature of that documentary, which elephants are linked into, is how we can use the skeleton to reconstruct some general aspects of the soft tissue anatomy, and thereby the physiology or even behaviour, of a giant titanosaur. Which brings me to this post’s subject: We dig up dinosaurs all the time, but what about digging into dinosaurs and using what’s preserved to reconstruct what isn’t? 

The "G-suit" compressive stocking that the fascia wrapped around elephant, and other large mammals, creates, and the underlying, interwoven muscles and tendons (hindlimb of a young Asian elephant).

Some of the “G-suit” compressive stocking that the fascia wrapped around elephant, and other large mammals, creates, and the underlying, interwoven muscles and tendons (hindlimb of a young Asian elephant that sadly died in captivity). Did some larger dinosaurs have something like this? I’d expect so.

Another view, more superficially, of that G-suit/stocking under the thick, tight skin of an elephant's leg.

Another view, more superficially, of that G-suit/stocking under the thick, tight skin of an elephant’s leg. You’ll hear more about this in the Attenborough show…

Once the documentary airs, I may be able to share some more images from it showing what they did for the titanosaur, but this BBC photo gives a good idea.

Once the documentary airs, I may be able to share some more images from it showing what they did for the titanosaur, but this BBC photo gives a good idea. Here, blood vessels and other tissues surrounding the skeleton. How would a titanosaur pump blood around its body? A good question.

I’ve covered the science behind these reconstructions before, along with the art (in numerous posts, actually). Here I want to inspect how it’s communicated through the media: what are good (and not so good?) ways to cover it, especially now that displaying raw anatomy is more tolerable on TV and other media? I’m not writing about Thanksgiving dinner dinosaur dissections; not really; or in technical terms how we build a dinosaur to dissect/depict internally (digitally or physically).

I wanted to focus more on the end product; the imagery or even physical object; and how it conveys what we think we know about dinosaur anatomy. I’ll do that via examples, using photos of dinosaur anatomy that I’ve collected over the years from museums or other media. There won’t be any profound points or long musings; it’s mainly a photo blog:

What your (inner?) child most needs is a dinosaur to dissect yourself! Why not a T. rex toy like this?

What your (inner?) child most needs is a dinosaur to dissect yourself! Why not a T. rex toy like this?

I could quibble, but for the price they did a good job.

For the price (~$30 in USA), the 4D Vision dinosaurs deliver a pretty good bargain, and the anatomy is satisfactory. I’ve been collecting this series. I could quibble, but hey: it’s a dinosaur you get to build/dissect yourself, and with many major organs in reasonable positions! Not so easy to put/keep together, but it’s fine. I would not pay a ton for it, though.

Poster of Velociraptor's anatomy I've had since grad school, adorning my office. For ~1996, it's damn good, mostly... (placeholder photos until I get to the office tomorrow and take better ones!)

Poster of Velociraptor’s anatomy I’ve had since grad school, adorning my office. For ~1996 (no feathers; “zombie hands“), it’s damn good, mostly… Closer views below (sorry, photo quality is crap– taking photos of wall poster turned out to be harder than I expected! Bad lighting.) :

Closeup of the leg muscles- hey, not bad!

Closeup of the leg muscles- hey, not bad! Pretty much the right muscles in the right places more or less, and plausible proportions. No air sacs in the torso, but again, this is mid-1990’s science shown. BUT…

I was happy with this poster until I got it home and read this final bit of text... Oh, America! You silly place.

I was happy with this poster until I got it home from the western-USA museum I bought it at and read this final bit of text… Oh, America! You silly place. (And unfortunately, these dinosaurs are not from the very end of the Cretaceous anyway, so “global catastrophe” is not implicated.)

Ornithomimid in Barcelona natural history museum. This was unexpected and got me excited when I first saw it.

Ornithomimid in Barcelona natural history museum. This was unexpected and got me excited when I first saw it.

Looking down onto the opened torso of the Barcelona ornithomimid. Strikingly realistic!

Looking down onto the opened torso of the Barcelona ornithomimid. Strikingly realistic! Breastbone, heart, liver, intestines; not unreasonable positions and sizes. No feathers, but again hey– this was made in the earlier days.

Skinned Albertosaurus from the Drexel Academy of Sciences. I forget where I got this pic but I like the display.

Albertosaurus from the Drexel Academy of Sciences. I forget where I got this pic but I like the display– this is an impressive full-scale physical model. The transition from skeleton-only on the left to skinned in the middle to fully-fleshed and popping out atcha on the right is clever.

?T. rex? leg, photo that I took ages ago as a PhD student, if memory serves. Can anyone remind me where this was? California Academy of Sciences?

?T. rex? leg, photo that I took ages ago as a PhD student, if memory serves. Can anyone remind me where this was? California Academy of Sciences? I am embarrassed that I cannot recall. I remember geeking out about it. It has a toy-ish look, but I reckon they had to build this to withstand kids touching it.

Perhaps the best example I've seen in a museum: the AMNH's sauropod with internal organs and their functions projected onto it. Bravo!

Perhaps the best dino-dissection example I’ve seen in a museum: the AMNH’s sauropod Mamenchisaurus with internal organs and their functions projected onto it, in the “World’s Largest Dinosaurs” exhibit. Bravo! I stood and watched it for quite a while.

This is far from comprehensive– just several kinds of imagery that I mostly like. There’s the tension between showing too much realism, which science simply can’t back up, and being too cartoonish, losing the viewer’s immersion in the time-travelling fantasy. I do, however, like other kinds of more abstract, schematic depictions of dinosaur anatomy that simplify the details to focus on the basics of what organs should have been where and how they may have worked, such as this depiction from T. rex Autopsy, which also took the other extreme favouring ultra-realism (but with physical models, not so much with the CGI):

AIr flow through a T. rex: simplified but clear.

Air flow through a T. rex: simplified but clear. CGI used to explain, not abused. The real air sac anatomy would be too complex to show. You may see something similar with the titanosaur show.

That’s enough for now. I’ve stuck with relatively recent examples; of course in my particular field I also think back to Romer’s wonderful 1920’s drawings, which I covered in this post.

So, blog readers, help me out here: what examples of dinosaur internal, squishy anatomy from museums, documentaries or other not-entirely-done-by-nitpicky-scientists venues do you like, or not like so much? What works for you, or at least is memorable in some way?

I think a lot about where my ideas come from as a researcher and what a “new” idea really is, in addition to the “value” (in any sense) of scientific ideas. As a senior researcher, I find more and more that such evaluations of the merits of ideas are a huge part of my job. And I hear my colleagues talking about similar things all the time. Variably, the reflections and discussions boil down to something like these (falling somewhere in the multi-dimensional space illustrated by two extremes below):

  1. “Study by so-and-so claims that it shows something novel but it’s not; such-and-such said/showed that in year XXXX”, or
  2. “I came up with the idea for the paper/grant and that is the most important thing”.

The above extremes, and perhaps all points in between, could always be debatable. There is no across-the-board, seemingly profound statement that can encompass all possibilities, like the ironically trite “There’s nothing new under the sun”, or vast oversimplification “Ideas are easy to come by; data are hard.”

What is a new idea and what is one worth? Well, yes, that varies in science. I think it’s helpful to dissect these issues separately- the origin and evolution of ideas, and then their currency in science. And so here I will do that. These are not new ideas– even for me; I’ve been sitting on this post since 18 October 2015, waiting for the ideas to coalesce enough to post this!

Stomach-Churning Rating: 1/10; ruminations, some of which may be blindingly obvious. No images; just a long read.

It’s safe to say, and I know a lot has been written about this in the history and philosophy of science, that almost all “new” ideas in science are incremental. They tend to be little steps forward; not Kuhn-ian revolutions that blindside the community. Fans of Darwin and other science heroes are constantly reminded that even the geniuses’ ideas emerged mostly from the tangled skein of scientific society; coalescing from particles suspended in the scientific group-think. That doesn’t devalue science, as science is still making big strides– by (increasingly?) small, frequent steps across the scholastic landscape (see below).

It’s easy to take a shortcut and say, for example, that evolution was Charles Darwin’s big idea (or give him the lion’s share of credit) when of course that is a huge oversimplification and highly misleading– historical evidence shows beyond question that evolutionary ideas had been bounced around for decades (or centuries) and that Darwin had come across plenty of them, his grandfather Erasmus’s Zoonomia being an obvious one out of many influences. I was recently teaching my main undergrad class about this very topic and it got me thinking more about how, on the more standard scale of us non-genius scientists, ideas always have many common ancestors and lateral transfer of heritable material (to abuse the evolutionary metaphor). Saltationism/macromutation of ideas is rare, hence precious when it truly does happen. But hybridization (multidisciplinary syntheses; integrative science; all the rage these days– usually for good reasons) is a powerful force, probably today more than ever in science, able to generate and tackle big ideas.

It’s just as easy to default to the breathless “Wow, everything is new!” shortcut. The 24-hour news cycle takes a regular tongue-lashing from scientists and other science communicators from taking this shortcut too often. We might more reflexively forgive that cycle in the breath after cursing it, because memories and attention spans are short, hectic lives are only a bit longer, and thus in the latest science news story the headline or ~500-word article can’t regale us with the entire, nuanced history of a subject *and* explain within those tight constraints what incremental advance has been made, with due credit to all antecedents. Would we prefer less science news coverage overall, to save that breathlessness for the rare occasion when it is truly deserved? Or just more boring, toned-down, long-winded coverage (cough, this post, cough?) that attracts less interest in science overall? I’d be wary of such arguments.

Scientific journal articles, too, are becoming more complex because of the increasingly specialized, technical nature of many fields that have benefited from prior scientific advances. Online journal formats are helping to loosen the noose of word limits on those articles. But good mentors (and reviewers, and editors) remind young (and all other) scientists that overly long papers will raise the risk of fewer people reading them or spotting key phrases buried in them. “Moderation in all things.” Usually. “Exceptions to all things”, too, I admit– sometimes long papers are great!

Furthermore, much as journalists can’t cover, or be familiar with, the whole history of a field, so it is becoming harder even for specialists to follow scientific progress within a specialized field. Open access to literature and online papers or emailed pdfs are helping, with even many very old classic papers becoming digitized. Yet then while you’re reading through some of the old literature you’d missed, and doing teaching and research and admin and other tasks that life as a scientist demands of you, new papers are popping up. You see some of them, and others get missed because there are too many papers getting published to follow them all, and because there are so many journals (many of the online ones being very generalist, so a paper on a given topic could appear anywhere), and even the best literature-searching tools don’t find everything. Patience, to a degree, in tolerating missed references is thus important, although it can help to point them out diplomatically.

I find it exasperating trying to keep up with the fields I work in. Seriously, I frequently look at my folders of papers “to read” and I think “*@$*! I’ll never read all that now!” Ten years ago it was different. I felt like I could, and I think I mostly did, keep up with my interests. Furthermore, I care about reading others’ research. I love reading science and I feel proud to keep up with a topic, knowing that I’m doing my scholastic duty. I want to learn what others have learned, both in the far past and far-flung countries and in the recent cutting-edge studies. I have gotten where I am from doing that– the literature routinely inspires me to take new directions in research and many of my best papers/grants/projects have come directly from that inspiration. I worry that I am missing opportunities for new ideas by not reading all of the old ones. But no one can do everything.

Aha! I have reached one of my points! The literature is there to show us the way; show us where the knowns and unknowns are in science. The peaks of knowledge where science has climbed to new heights of understanding! The valleys of ignorance where a bit of research effort or luck might get you far in making “new” discoveries! Or you can slog it on the slopes and try to conquer the peaks on that scholastic landscape (Sewall Wright fans, take note); show that your disciplinary Mt. Everest is taller than anyone thought it was. We all have our favoured routes as researchers. The point is to discover something “new” to science. It is all new, if it is worth doing, as a scientific researcher. And maybe 99.99% of that newness ascends from base-camps on older, lower landscapes.

But there is new (tiny steps), and then there is NEW (quantum leaps), and we must be wary of that’s-not-even-new-at-all (previously charted territory, or even plagiarism). The aspect of “new”-ness here that interests me is the subjective judgement we make in assessing that originality. As an example from my own research in vertebrate palaeontology, I’ve published around 12 papers that orbit the topic of whether a big theropod dinosaur such as Tyrannosaurus rex could run quickly if at all. This all began with my 2002 paper in Nature, which at the time was a “new” application in palaeontology of methods that were well over 30 years old then (inverse dynamics analysis of musculoskeletal mechanics), and owed a lot to simpler approaches by RMcNeill Alexander and others, but probably was published (and gained me some notoriety/infamy) because it answered a tough question in a clever, basic and reproducible way.

My (and coauthors’) papers in 2004, 2005, 2007 and onwards fleshed out this topic more and showed some of the nuances overlooked in that 2002 study. They were all “new”, even though that question “Was T. rex a fast runner?” was gradually beaten to death by them to the point where even I am tired of it now, although I can still see areas where I’m not satisfied with my own answers. I guess the 2002 paper was NEW in its own moderate way and the later papers, even though some of them were much fancier (e.g. using 3D imaging and cutting edge computer modelling; not just simple equations and sketches), were incrementally new in terms of the answers they gave, even if methodologically NEW-ish. We could debate the finer details of the “new-ness” there until the heat death of the universe, but I doubt it would be of more than of very niche (read: tediously nerdy and semantic/subjective) interest. Debating whether something is new or not quickly gets boring. It’s a dull criticism to level at a new study, because most studies (at least in my field) are conducted and published for a good reason and probably are new in some way; the ways they are not new are far less interesting. It’s maybe even harder to accurately delineate the “new-ness” of a study than it is to berate it for its old-ness; the latter is the knee-jerk retort too often on social media, perhaps, and easily fuelled by scientific self esteem issues.

Returning to point 1 above, then, sure. That study in year XXXX by so-and-so probably does have some relationship to the latest studies in a related field. And it behooves us as scholars to be aware of those homologies and homoplasies that are the history of any scientific discipline’s intellectual evolution. But giving the authors or the news media a tongue-lashing for talking about (incrementally) new research probably is more often wasted breath than otherwise; boiling down to debate over which hairs have been split and by whom and when. There are plenty of cases of excessive spin and hype, my personal punching-bag being the humdrum T. rex “scavenger” nonsense, but I usually find it more rewarding to look for the value in scientific ideas and data than excoriate the excesses of how they are presented to the public.

What’s more interesting, to me, is how weaving together old research to allow new ascents up scholastic landscapes moves science forward, sometimes in surprising ways. Old research provides data and ideas that are ancestors of new ideas and eventually new data. Indeed, this reticulating phylogeny of data and ideas muddies the waters between “data” and “ideas” in some cases. We need both, and different researchers fall into different positions along a spectrum. I see some scientists who take an “r selection” approach to ideas, throwing them out in a shotgun approach (sometimes with little or no peer review to control their quality) and hoping that some stick, adhering to supportive data. In contrast, other scientists fall closer to the “K selection” extreme, slowly nuturing ideas with cautious care, focusing on building up mountains of rigorous data to test those ideas with, until together they are ready to leave the academic nest and be published.

The integration of data and ideas from old research plays a variable role in that evolution of data and ideas– some of those scientists (falling on any point along that r-K spectrum) rely more on careful reading of past scientific literature to give their work firm historical footing and inspiration, whereas others mostly pluck a few references that they need to cite once they write up their work, not so keen on spending their time keeping up with the literature and thus focusing more on their own internal thought processes or other sources of inspiration. Different strokes for different folks…

What I’d like to close with, as a roughly second point of this post, is to question the inherent value of scientific ideas. I emphasize that I am unable to provide any easy answers here. What is the value of a good idea that needs testing by some kind of data? The source of inspiration may be immaterial to that evaluation; where one got one’s ideas may not matter here, it’s more about the value of the idea at hand– be it a hypothesis, a general question, a “what’s up with that?” (my personal favourite kind of research question); whatever.

For example, I can think of many cases in my career where a certain paper or grant owed hugely to an idea I had; without that idea, which wasn’t initially obvious, we’d still be stuck at some lower scientific base-camp, and big papers or grants or whatever would not have happened, and careers might not have blossomed the way they did (who knows!). My job as a senior researcher is often to “give away” ideas to those I mentor and collaborate with, and I love doing that. It’s seldom one-sided, with me playing the parthenogenetic parent and that’s it; normally these processes are intensely collaborative and thus multiparental hybrids. But I can usually trace back where the lineages of ideas came from and weigh their merits accordingly, and sometimes as scientists we have to do that.

However, it’s not just about ideas, either– a great scientific idea can be wonderfully valuable, but until it is tested its value might only be speculated upon. It takes the infamously time-consuming and technically challenging procedure of scientific  data collection and analysis to test most ideas, and different collaborators may play lesser or greater roles in that process vs. the ancestral idea-generating process(es). Along the way, we must think of ideas for how to test the main idea itself: what methods might work, what has or hasn’t been tried before to tackle similar problems, and is the method we’ve chosen even working as the scientific work proceeds or must we switch approaches? That gets messy; ideas and data begin to become entangled, and contributions of individuals intermingled, but that’s how science works.

This leads to the flip side of the value of scientific ideas, that in many cases they aren’t worth that much— they may be dead-ends for one reason or another: just foolish ideas; or untestable with current tools/data; or so obvious that anyone could have come up with them; or boring and not really worth trying to test. I’ve found it common to publish a paper and then hear, at some point before or after publication, another researcher say (in reference to some major or minor aspect of the paper) something like “Hey I mentioned that idea in this paper/book/blog post!” More often than not, I don’t want to say it in retort but my reaction is “Well, duh. It’s a pretty obvious idea”, and/or “That’s great, but you didn’t test it; that’s the hard bit”. Cheap ideas by definition aren’t worth much fuss. To abuse Shakespeare, “The science is the thing; wherein we’ll catch which idea in science is king.” (sorry!)

A common example I run across that falls within this theme of cheap ideas is to encounter a colleague (e.g. a new student, maybe one with lax supervision) who describes their new research project in which they apply some sort of fancy technique like computer modelling/simulation to an animal, such as a nice dinosaur fossil, doing what some previous study/studies had done with other species but applied to a new species. Uncomfortably often, when asked their justification for applying that method to that animal is because they can, and because they happen to have that animal accessible, rather than because there is an urgent, exciting question that must be answered for which that method and specimen are ideally suited to testing. It’s not worthless, but… more emphasis on the value of ideas and less on climbing Mt. Everest because it’s there might have been rewarding?

Returning to the main thrust of this post conveyed by the title, then, it’s not easy evaluating what the value of an idea is in science, but it’s something that we all have to learn to do as researchers, and it can bring out the best and worst of our humanity as scientists; perhaps leading to conflict; or it can even just end up with an unsatisfyingly muddled answer. So tread carefully on that scholastic landscape, and think about how you choose your way across it– there are many routes, but I think we can generally agree that the prize of discovery (whether incrementally small or uncommonly large) is a big part of why we dare the journey.

I’d love to hear your thoughts, your stories, and other insights here– it’s a very broad topic and lots of room for discussion!

Greetings Freezerinos, and Happy New Year! I have been quiet on this blog for health and other reasons but those will pass and there will be new posts in 2016. However, behind the scenes there have been super-cool things afoot. I am very happy to bring one of them to you now:

(but first: Stomach-Churning Rating: 6/10; video below shows a dissected sea turtle foot in motion)

We have just debuted our new social media “presence” (for lack of a better word) that is a sister blog to this one. It is called Anatomy To You (http://anatomytoyou.com/), as its intent is to bring a wide array of science about animal anatomy to “you”, the general public. This John’s Freezer blog will continue with it’s style of rambling longer posts targeted at a fairly geeky scientifically literate audience and focusing on my team’s research and my own disparate thoughts about science and related issues. Anatomy To You will bring you shorter posts, even just images, completely focused on celebrating the structure of organisms, and not just presenting my team’s research but also a wide array of anatomical science from around the globe. It will also be much more regular and frequent in its posts. We’ll welcome guest posts and I encourage you to get in touch with us if you want to jump on the bandwagon early, or have us feature your research for you!

More about the ATY blog is here, but there is also a Twitter feed and Facebook account. Our first major posts are on what skeletons are, and on a dissection of some sea turtles. Please follow us and join in the celebration of anatomy! My team’s scientific communicator/technician Dr. Lauren Sumner-Rooney is spearheading this ATY effort with me, so please follow her too!

Anatomy To You will continue to evolve over this coming year, so please stay with us and give us feedback; join in the morphological conversations with us. I am SUPER excited to see where this goes– it is an experiment that has a lot of potential, we think.

Sea turtle from our ATY dissection, foot muscles in action (found dead in the wild; don’t be ridiculous, we don’t kill sea turtles for our research)

Seeking adaptations for running and swimming in the vertebral columns of ancient crocs

A guest post by Dr. Julia Molnar, Howard University, USA (this comes from Julia’s PhD research at RVC with John & colleagues)

Recently, John and I with colleagues Stephanie Pierce, Bhart-Anjan Bhullar, and Alan Turner described morphological and functional changes in the vertebral column with increasing aquatic adaptation in crocodylomorphs (Royal Society Open Science, doi 10.1098/rsos.150439). Our results shed light upon key aspects of the evolutionary history of these under-appreciated archosaurs.

Stomach-Churning Rating: 5/10; a juicy croc torso in one small photo but that’s all.

Phylogenetic relationships of the three crocodylomorph groups in the study and our functional hypotheses about their vertebrae. * Image credits: Hesperosuchus by Smokeybjb, Suchodus by Dmitry Bogdanov (vectorized by T. Michael Keesey) http://creativecommons.org/licenses/by-sa/3.0

Phylogenetic relationships of the three crocodylomorph groups in the study and our functional hypotheses about their vertebrae. * Image credits: Hesperosuchus by Smokeybjb, Suchodus by Dmitry Bogdanov (vectorized by T. Michael Keesey) http://creativecommons.org/licenses/by-sa/3.0

As fascinating as modern crocodiles might be, in many ways they are overshadowed by their extinct, Mesozoic cousins and ancestors. The Triassic, Jurassic, and early Cretaceous periods saw the small, fast, hyper-carnivorous “sphenosuchians,” the giant, flippered marine thalattosuchians, and various oddballs like the duck-billed Anatosuchus and the aptly named Armadillosuchus. As palaeontologists/biomechanists, we looked at this wide variety of ecological specializations in those species, the Crocodylomorpha, and wanted to know, how did they do it?

Of course, we weren’t the first scientists to wonder about the locomotion of crocodylomorphs, but we did have some new tools in our toolbox; specifically, a couple of micro-CT scanners and some sophisticated imaging software. We took CT and micro-CT scans of five fossil crocodylomorphs: two presumably terrestrial early crocodylomorphs (Terrestrisuchus and Protosuchus), three aquatic thalattosuchians (Pelagosaurus, Steneosaurus, and Metriorhynchus) and a semi-aquatic modern crocodile (Crocodylus niloticus). Since we’re still stuck on vertebrae (see, e.g., here; and also here), we digitally separated out the vertebrae to make 3D models of individual joints and took measurements from each vertebra. Finally, we manipulated the virtual joint models to find out how far they could move before the bones bumped into each other or the joints came apart (osteological range of motion, or RoM).

 

Our methods: get fossil, scan fossil, make virtual fossil and play with it.

Our methods: get fossil (NHMUK), scan fossil, make virtual fossil and play with it.

Above: Video of a single virtual inter-vertebral joint from the trunk of Pelagosaurus typus (NHMUK) showing maximum osteological range of motion in the lateral direction (video). Note the very un-modern-croc-like flat surfaces of the vertebral bodies! (modern crocs have a ball-and-socket spinal joint with the socket on the front end)

While this was a lot of fun, what we really wanted to find out was whether, as crocodylomorphs became specialized for different types of locomotion, the shapes of their vertebrae changed similarly to those of mammalian lineages. For example, many terrestrial mammals have a lumbar region that is very flexible dorsoventrally to allow up-and-down movements during bounding and galloping. Did fast-running crocodylomorphs have similar dorsoventral flexibility? And did fast-swimming aquatic crocodylomorphs evolve a stiffer vertebral column like that of whales and dolphins?

Above: Video of how we modelled and took measurements from the early crocodylomorph Terrestrisuchus gracilis (NHMUK).

Our first results were puzzling. The Nile croc had greater RoM in side-to-side motions, which makes sense because crocodiles mostly use more sprawling postures and are semi-aquatic, using quite a bit of side-to-side motions in life. The part that didn’t make sense was that we found pretty much the same thing in all of the fossil crocodylomorphs, including the presumably very terrestrial Terrestrisuchus and Protosuchus. With their long limbs and hinge-like joints, these two are unlikely to have been sprawlers or swimmers!

So we started looking for other parts of the croc that might affect RoM. The obvious candidate was osteoderms, the bony scales that cover the back. We went back to John’s Freezer and got out a nice frozen crocodile to measure the stiffness of its trunk and found that, sure enough, it was a lot stiffer and less mobile without the osteoderms. If the fairly flexible arrangement of osteoderms in crocodiles had this effect on stiffness, it seemed likely that (as previous authors have suggested; Eberhard Frey and Steve Salisbury being foremost amongst them) the rigid, interlocking osteoderms running from head to tail in early crocodylomorphs would really have put the brakes on their ability to move their trunk in certain ways.

Testing stiffness of crocodile trunks to learn the effects of osteoderms, skin, muscles, and ribs. We hung metric weights from the middle of the trunk and measured how much it flexed (Ɵ), then removed bits and repeated.

Testing the stiffness of (Nile) crocodile trunks to learn the effects of osteoderms, skin, muscles, and ribs. We hung metric weights from the middle of the trunk and measured how much it flexed (Ɵ), then removed bits and repeated. Click to em-croccen.

Another cool thing we found was new evidence of convergent evolution to aquatic lifestyles in the spines of thalattosuchians. The more basal thalattosuchians, thought to have been near-shore predators, had stiffness and RoM patterns similar to Crocodylus. But Metriorhynchus, which probably was very good at chasing down fast fish in the open ocean, seems to have had greater stiffness. (The stiffness estimates come from morphometrics and are based on modern crocodiles; see here again, or just read the paper already!) A stiff vertebral column can be useful for a swimmer because it increases the body’s natural frequency of oscillation, and faster oscillation means faster swimming (think tuna, not eel). The same thing seems to have happened in other secondarily aquatic vertebrate lineages such as whales, ichthyosaurs, and mosasaurs.

So, our results were a mixed bag of adaptations particular to crocs and ones that seem like general vertebrate swimming specializations. Crocodylomorphs are important because they are the only group of large vertebrates other than mammals that has secondarily aquatic members and has living members with a reasonably similar body plan, allowing us to test hypotheses in ways that would arguably be impossible for, say, non-avian dinosaurs and birds. The take-home message: crocodylomorphs A) are awesome, and B) can teach us a lot about how vertebrates adapt to different modes of life.

Another take on this story is on our lab website here.

I was recently featured on Daily Planet, a great Canadian science show on TV that lamentably is not broadcast more globally. It is always high quality science communication, aided by the superb hosts Ziya Tong and Dan Riskin (and a talented crew!). What were we doing? Dissecting an elephant’s foot, of course!

Stomach-Churning Rating: 9/10; no-holds-barred dismantling of elephant feet, from the video onwards, and this post is heavy on moist, goopy photos afterwards, with some nasty pathologies. Not nice at all. I’ll give you a chance to turn around while contemplating the cart that we use to carry elephant feet around campus (each foot is 20-30kg; up to 70lbs; so we need the help!), before the video.

no_poo

Here is a snippet of the full segment from Daily Planet:

And here is more of some of my recent dissections. I’ll walk you through two dissections, via photos. This goes back to the roots of this blog: unflinching, gritty examinations of real anatomy! Of course, no elephants were harmed for this work. They died at EU zoos/parks and were sent to me for postmortem examination and research, so we hope that this benefits the future care of elephants. We’re currently finishing up a grand overview paper that describes all of the odd pathologies we’ve observed in elephant feet, for the benefit of zoo keepers and vets who are trying to detect, diagnose and monitor any foot problems.

As the post’s title alludes, elephant feet (and more proximal parts of the limbs) are no stranger to this blog. If you’ve forgotten or are unfamiliar, here are some of my past proboscidean-posts: on elephant foot pathologies (a close sister post to this one), our “six-toed” elephants paper, how to make a computer simulation of an elephant’s limb (umm, paper yet to come!), how we boil and bleach bones to clean them up, and a few others. Last but not least, there was the post that went viral in the early #JohnsFreezer/WIJF days: dissecting an elephant with the “Inside Nature’s Giants” show.

There are two feet in this post, both front right feet (manus is the technical term; singular and plural). The first one is the messier (unhealthy and bloodier, less fresh and clean) one, from the show/video. It is an Asian elephant (Elephas maximus). I kick off with photos I took after the filming, so the foot is already deconstructed:

Skinned foot, oblique front/inside view.

Skinned foot, oblique front/inside view. The wrist is on the right side of the photo; the toes on the left.

Sole ("slipper"), with a hole on the fourth toe showing where the abscess is that let infection in/pus drain out.

Sole (“slipper”), with a hole on the fourth toe showing where the abscess is that let infection in/pus drain out. The slipper here is upside-down.

Top-down view of the sole of the foot, once the slipper is removed.

Top-down view of the sole of the foot, once the slipper is removed; flipped over and rotated 90 degrees clockwise from the above photo. Some of the fat pad of the foot is on the right side of the image; it’s very hard to separate from the keratinous sole of the foot.

Looking down into the fourth toe's abscess on the other side of the above view.

Looking down into the fourth toe’s (ring finger) abscess on the other side of the above view.

Looking down into the third (middle) toe, same view as above. Some redness and greyness where this toe had some of its own pathological issues.

Looking down into the second toe (index finger), same view as above. Some redness and greyness where this toe had some of its own pathological issues like infection and a smaller abscess.

Looking up from the slipper at the fat pad and toes of the foot, where they interface with the sole/slipper. The fat pad is toward the bottom and left side; the five toes are on the upper/right side (knobby subcircular regions on the perimeter of the foot).

Looking up from the slipper (removed) at the fat pad and toes of the foot, where they interface with the sole/slipper. The fat pad is toward the bottom and left side; the five toes are on the upper/right side (knobby subcircular regions on the perimeter of the foot). The very bad infection on the fourth toe is visible on the bottom right.

The sproingy fat pad is worth a video!

And one good wiggle deserves another!

A view down onto the wrist joint. The carpal (wrist) bones are visible at the bottom of the image, whereas the flexor (palmar) tendons and muscles on the back of the "hand" are at the top. There is a LOT of musculotendinous tissue on the back side of an elephant's foot.

A view down onto the wrist joint. The carpal (wrist) bones are visible at the bottom of the image, whereas the flexor (palmar) tendons and muscles on the back of the “hand” are at the top. There is a LOT of musculotendinous tissue on the back side of an elephant’s foot. As you will see in my dissection of the second foot, further below!

Looking down onto the medial (inner/"thumb") border of the foot, where I've exposed the prepollex, or false "sixth finger" by removing the first metacarpal (knuckle) bone.

Looking down onto the medial (inner/”thumb”) border of the foot, where I’ve exposed the prepollex, or false “sixth finger”, by removing the first metacarpal (knuckle) bone.

Removed the prepollex from the foot. The white oval structure is the top of the prepollex; white is cartilage, whereas the red "islands" are blood vessels that have invaded the cartilage and are starting to turn it into patches of bone. So this prepollex is at a very early stage of bone formation, still almost entirely cartilaginous, whereas some older elephants have the prepollex largely formed of bone.

I’ve removed the prepollex from the foot. The white oval structure (bottom right) is the top of the conical prepollex, where it connected to the rest of the foot. White is cartilage, whereas the red “islands” are blood vessels that have invaded the cartilage and are starting to turn it into patches of bone. So this prepollex is at a very early stage of bone formation, still almost entirely cartilaginous, whereas some older elephants have the prepollex largely formed of bone. The fleshy pink tissue adhering to the surface of the prepollex here is a remnant of “abductor” muscle that connects it to the thumb and thus could allow some active control of the prepollex’s mobility.

Well, that was one very pathological elephant’s foot; one of the worst I have ever seen. Every foot I dissect is different and tells me a unique story about that animal’s development, history and health. This one told a very sad tale. What does a somewhat normal elephant’s foot look like? I thawed one out for comparison, and to thin out my overstuffed freezer stock. This one starts off from an intact (if severed) foot so you can witness the stages of dissection:

Whole foot. African elephant (Loxodonta africana).

Whole foot. African elephant (Loxodonta africana). You may spot in later photos that the second and fourth toes’ nails are cracked longitudinally. This happens sometimes in elephants without any obvious health problems such as infection, but if it lasts long enough and conditions are bad enough (e.g. unsanitary conditions getting bacteria into the crack; spreading the crack to let them into the foot tissue), it could worsen.

Nice clean sole.

Nice clean sole. No abscesses or other problems. You can faintly see the cracked toenails here.

Gorgeous white cartilage surfaces of the wrist joints. Nice and healthy-looking. A young animal, in this case.

Gorgeous white cartilage surfaces of the wrist joints. Nice and healthy-looking. A young animal, in this case.

Removing the skin; nice soft whitish connective tissue underneath.

Removing the skin; nice soft whitish connective tissue underneath.

Skinned foot; rear view. The yellowish fat pad is wonderfully visible through the connective tissue sheath.

Skinned foot; rear view. The yellowish fat pad is wonderfully visible through the connective tissue sheath.

Skinned foot; front view. The thin, broad extensor tendons that would draw the fingers forward in life are visible here as longitudinal lines along the foot's surface, running to the toes.

Skinned foot; front view. The thin, broad extensor tendons that would draw the fingers forward in life are visible here as longitudinal lines along the foot’s surface, running to the toes.

Ahh, my favourite thing! I've cut around the prepollex and am pointing at it. It's almost impossible otherwise to see through all the fatty tissue of the fat pad that surrounds it.

Ahh, my favourite thing! I’ve cut around the prepollex and am pointing at it. It’s almost impossible otherwise to see through all the fatty tissue of the fat pad that surrounds it.

Removing the prepollex. It's tiny and enmeshed in connective tissue; harder to see than in the first elephant (photos above).

Removing the prepollex. It’s tiny and enmeshed in connective tissue; harder to see than in the first elephant (photos above).

There is the prepollex! Maybe 12cm long. A little bit of cartilage (white) visible where it connected to the foot. These "sesamoid bones" vary tremendously in elephants I've inspected. I am still getting my head around that, after >10 years of staring at them in >75 feet!

There is the prepollex! Maybe 12cm long. A little bit of cartilage (white) visible where it connected to the foot. These “sesamoid bones” vary tremendously in elephants I’ve inspected. I am still getting my head around that, after >10 years of staring at them in >75 feet!

Gap left by removal of the prepollex, on the median border of the foot; thumb region. Imagine having a little extra thumb growing off the base of your thumb and sticking toward your palm. That's what elephants have.

Gap left by removal of the prepollex, on the median border of the foot; thumb region. Imagine having a little extra thumb growing off the base of your thumb and sticking toward your palm. That’s what elephants have.

Here, removing the slipper/sole of the foot, from the back side forwards. Hard work!

Here, removing the slipper/sole of the foot, from the back side forwards. Hard work!

The slipper. Compare with the image above (same orientation). Nothing wrong here that I could see.

The slipper. Compare with the image above (same orientation). Nothing wrong here that I could see.

Front view of the toes, where they connect to the toenails. This specimen was so fresh that they were surprisingly easy to cut through and remove the foot from the sole.

Front view of the toes, where they connect to the toenails. This specimen was so fresh that they were surprisingly easy to cut through and remove the foot from the sole.

Looking up at the palm. You can see the bulbous fat pad (yellower tissue) bulging out in the centre of the palm, and segments of it extending between each finger, separated by fibrous tracts. I love this anatomy. I can stare at it for hours and still be fascinated after all these years. So complex!

Looking up at the palm. You can see the bulbous fat pad (yellower tissue) bulging out in the centre of the palm, and segments of it extending between each finger, separated by fibrous tracts. I love this anatomy. I can stare at it for hours and still be fascinated after all these years. So complex!

Looking down onto the inside of the toenails, toes 3 and 4. Healthy, relatively intact tissue; no swelling or bleeding or other pathology.

Looking down onto the inside of the toenails, toes 3 and 4. Healthy, relatively intact tissue; no swelling or bleeding or other pathology.

Skinned foot, oblique front/inside view again, as above.

Skinned foot, oblique front/inside view again, as above.

Fat pad removed, looking up through where it was at the palm of the "hands", where the tendons and ligaments connect to the five toes. Each arc-like structure is a toe; the "thumb" (first toe) is on the upper left.

Fat pad removed, looking up through where it was at the palm of the “hands”, where the tendons and ligaments connect to the five toes. Each arc-like structure is a toe; the “thumb” (first toe) is on the upper left.

Elephant's-eye-view looking down onto the fat pad, where the palm of the foot in the image below would be placed in life.

Elephant’s-eye-view looking down onto the fat pad, where the palm of the foot in the image below would be placed in life (i.e. the limb would be coming down vertically, perpendicular to the plane of the image). The fat pad of the foot is visibly thicker toward the back of the foot (bottom of the image), as you’d expect, because the toes occupy most of the front parts.

Palmar tendons and muscles; the common digital extensor muscle group. Clenches the toes. Not a small muscle, either!

Palmar tendons and muscles; the common digital extensor muscle group, which clenches the toes. Not a small muscle, either!

Tendons of the digital flexor muscle exposed.

Tendons of the digital flexor muscle exposed.

Removed the digital flexor muscle so the three major tendons can be seen (the two short side branches to the first and fifth toes have been cut off).

I removed the digital flexor muscle so the three major tendons can be seen (the two short side branches to the first and fifth toes have been cut off).

Forefoot with flexor tendons removed, revealing the channels that they coursed through.

Forefoot with flexor tendons removed, revealing the channels that they coursed through.

Closeup of the glistening channels for the flexor tendons. They are lined with lubricative tissue to help the tendons glide through them. And the tendons do need to be able to glide- although elephant feet look very solid from the outside, and are to an extent, but we've done studies showing that they do move if you apply even a moderate load to them in a cadaver, and thus would move in life, too.

Closeup of the glistening channels for the flexor tendons. They are lined with lubricative tissue to help the tendons glide through them. And the tendons do need to be able to glide- although elephant feet look very solid from the outside, and are to an extent, but we’ve done studies showing that they do move if you apply even a moderate load to them in a cadaver, and thus would move in life, too.

Let’s finish off with some osteology, shall we? First the unhealthy Asian elephant, then the healthy African elephant; same front right feet, just the bones (from my CT scans):

Ouch, indeed!

Much better. And that’s the end!

Wow, that was an elephantine post! I wanted to take yet another opportunity to share the amazing anatomy of elephant feet with you. You’re all now qualified experts if you made it this far!

Any questions?

Goat To Be Seen

Goat morphology is cool! (from work with local artist)

I posted the above photo once before, but didn’t explain any of the fun details of artist-designer Thomas Thwaites‘s visit to the RVC to dissect a goat with us. Now his show has just finished in London, celebrating the end of his project and the near-completion of his book about his experience trying to live life as a goat. This week, I went to his east side gallery and had some time to chat with Thomas about his transhuman experiences. Because the project has a strong biomechanics, anatomy, art and science theme to it, I’m posting a photo-blog post about all of that. It’s goat to be seen to be believed! I for one wouldn’t mind being a goat right now; I could use a break from my decrepit body…

Stomach-Churning Rating: Too late, there’s the goat pic above and more like it below. I’d give those a 8/10; no kidding. The puns make it worse, too.

The context

The context. Thomas never did get to gallop (sorry, spoiler!) but he did manage a trot, and some other capricious behaviours. I forgot to ask him if he’d tried the Goat Simulator. I have; it’s good for an hour of fun hircosity.

Starting the dissection at the RVC.

Starting the dissection at the RVC, to get inside a goat.

Hide.

Hide.

Fore- and hindlimbs.

Fore- and hindlimbs; comparative design for inspiring prosthetics.

Dissections!

Dissections on display!

Prototype goat-suits. Their mobility was too limited.

Prototype goat-suits. Their mobility was too limited.

The prototype in the foreground could not move without falling down.

The prototype in the foreground could not move without falling down.

Goat-suit shots.

Inhabited-goat-suit shots.

The Goat-Suit: custom made prothetics, a helmet, and some form-fitting casts.

The final Goat-Suit: custom prosthetics, a helmet, and some form-fitting casts.

Thomas Thwaites with the goat-suit.

Thomas Thwaites with the goat-suit.

The forelimb prosthesis. I was worried it would hurt his wrists but apparently it transferred the loads mainly to the forearms.

The forelimb prosthesis. I was worried it would hurt his wrists but apparently it transferred the loads mainly to the forearms. It was made by a prosthetics clinic up in Salford.

Showroom

Photos from rambling around the Swiss Alps in the goat-suit with goats.

Trip-trap-trip-trap...

Trip-trap-trip-trap… (but no trolls)

Goat-suit in action!

Goat-suit in action! With Goat-Pro camera, I see.

Acceptance?

Acceptance?

And the goat that we had dissected, skeletonized at RVC and re-articulated by Thomas:

Do goats wish they were human?

Do goats wish they were human?

What are you looking at?

What are you looking at?

Close-up of goat head.

Close-up of goat head and shoulders.

Goat hooves-on-hips

Goat hooves-on-hips; a gruff pose.

So like us.

So like us.

Excellent post by a summer research student on my team!

From BSc to the future: the journey of a locomotion student

I spent this summer, the second of my undergraduate degree, in the Royal Veterinary College’s Structure and Motion Laboratory, as I undertook a BBSRC-funded Summer Research Experience Placement. The purpose of the REP is to give undergrad students a taste of what research would be like as a career. In my case, I was given the fantastic opportunity to study giraffe locomotion. Mentored by Christopher Basu, a PhD student in the SML, and Professor John Hutchinson, my ten-week project began at the start of July.

First things first, I had some ground work to do. All the data had been collected prior to my placement, though I will be joining Chris next week to collect fresh data for his future work. Giraffes were recorded using high speed video cameras walking parallel to the edge of their enclosure, over concealed force-plates measuring ground reaction forces. I was provided with 3 days’…

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