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2021-2022: “over and over again & again” sums it up. I do love this band I “discovered” in 2021 though. Finding new music has been a joy for me through these tough recent years.

The pandemic goes on; my life goes on; but it has been another rough 1+ years. I have hardly done any hands-on anatomy as I’m hardly on campus at all, and my team’s work has mostly shifted into digital modelling for now (more about that below; it is not a bad thing though). My main news for 2021-2022 falls into the categories of Life Stuff, and Work Stuff to summarise here. “WTF” sums it up as it has been a… strange time; very challenging at a personal level, due to the Life Stuff.

Stomach-Churning Rating: stuff is weird, but nothing truly stomach-churning is here

Life Stuff: It’s been about the same as 2020-2021; summarised here. Thankfully, no major grief from losing people/pets close to me, this time. But my heath has been really awful instead — my epilepsy returned in May 2021, much to our surprise, after 2 years of remission. I suspect dehydration was a cause, as I later found out that I’d been chronically dehydrated, which came as a shock. I’ve since learned to step up my hydration routine, and I feel better. Right now I’m >5 months seizure-free, after a very hard time of monthly seizures for ~5 months in a row, including a scary one after a flight from Phoenix-London, in which I woke up in a toilet stall at Heathrow baggage claim, very disoriented and alone, eerily with no one in that large men’s loo area. My taxi driver was wondering why I was so late… I am glad I didn’t fall and hurt myself with no one around. Fingers crossed that doesn’t happen again. But on top of that, I’ve been fighting a longstanding chronic illness (details are not necessary) at the same time, and that got very bad in April 2022, sending me to hospital with severe internal infection; very life-threatening, painful and frightening. Again, right now I feel that I’m in recovery, and grateful for some good (overall) care from the NHS. Owing to these health problems though, plus the pandemic and financial challenges, I’ve not been travelling and don’t foresee much of that for my near future. Which also means not enough real holiday; “staycations” in my house just aren’t enough, as I’ve been here for ~2.5 years. I’m starting to do more fun things, finally, again, and that led to this blog post (first one in almost one year). I feel I have some energy to do things that I enjoy again.

Walking tinamou bird XROMM animation

Work Stuff: Mostly that has been pretty good, with a caveat. The DAWNDINOS project still dominated my work life, much to my pleasure. Indeed, just this week I tied the final ribbon on that, formally, with submission of my final grant report to the EU/ERC. The grant ended on March 31, 2022 and I was VERY, VERY sad to have to bid farewell to my team, who I hugely enjoyed working with for those 5.5 years. Now comes the caveat to “work is good”, which is that suddenly I have no funding (feast-to-famine) and “just” one PhD student (Vittorio LaBarbera; reinforcement learning simulations of locomotion); MRes student Georgia Wells just finished; and a Research Fellow (Dr. Masaya Iijima). It looks like I’ll be doing more undergrad research projects than postgrad for awhile, but we’ll see. The grant funding lottery can be hard to predict. Regardless, there’s a lot of fun science going on! With DAWNDINOS, since last summary we’ve cranked out a bunch of cool papers on archosaur locomotor biomechanics — find them here. #25-31 are the newer ones I haven’t blogged about anywhere yet; #25, 28 and 30 are blogged about by Dr. Ashleigh Wiseman here; and #30 (which is, in part, a summary of DAWNDINOS to date) got SICB conference coverage here.

Muscle-bound Euparkeria hindlimbs from our DAWNDINOS paper #28; picture by Oliver Demuth.

DAWNDINOS paper #26 with DAWNDINOS postdoc Dr. Delyle Polet was a serendipitous one inspired by him giving a seminar to our lab when he first came to the UK, and it struck me that his method for using biomechanical simulations with the “Murphy number” (related to pitch moment of inertia; MOI) to test how animals move would work really well with a long-bodied, hefty Triassic pseudosuchian (= large pitch MOI) such as Batrachotomus, whose results we could compare with known fossil trackways of similar archosaurs (e.g., Isocheirotherium). We found evidence for it using at least two running gaits, which was pretty surprising.

Walking/running Batrachotomus 2D simulation, matching tracks (blue+red).

And just this week we published another “spin-off” paper (also see van Beesel primate shoulder-modelling studies #17,#29) adapting our 3D digital modelling methods to another taxon. This one came out of left field for me (I’d never expected I’d work on sharks!) but actually fits very well with my research interests in giant animals, biomechanics and palaeontology. We reconstructed the giant shark Otodus megalodon from the best fossils available (including a Belgian vertebral column somewhat neglected since the 1860s), finding that it was ~16m long and >60,000 kg; but this is not the largest it could get, as a vertebra ~50% larger is known! This paper got a LOT of nice press attention, and the video below is perhaps the best science communication release I’ve been involved with (all kudos go to Catalina Pimiento and the animation team she commissioned). Very importantly, the key data are free to use.

Explanatory video by @cookedillustra, Ian Cooke-Tapia

LATE ADDITIONS: But it wasn’t all #DAWNDINOS-related research! I was very pleased to have Dr. Chris Basu’s PhD work with me on giraffid locomotor biomechanics published in PNAS. We showed, with experiments and computer simulations, that Giraffa has unusually low overall leverage (“effective mechanical advantage”; EMA) for its forelimbs during walking (and presumably all gaits/speeds); and even its cousin Okapia does, to a degree; and the extinct giant giraffid Sivatherium too. This is because of its long limbs, which one might look at and call it “cursorial adaptation” but our analysis reveals the tradeoffs of that; as limb length goes up, EMA goes down, and that negatively impacts athletic abilities. All the more reason to be wary of simplistic length-speed conclusions from extinct animals (calling T. rex!). This, with the similar paper on elephant EMA we published in 2010, is one of my papers I’m proudest of; even though neither (curiously) got much (if any) media/other attention. So it goes.

Above: OpenSim simulation of left forelimb of Giraffa during walking; in ~real-time, representing one ground-contact (stance) phase. Green arrow = ground-reaction force (GRF); red lines = major muscle lines of actions (the simulation activated/deactivated them, producing forces to counter the GRF). EMA is the ratio of the muscles’ leverage vs. GRF leverage around joints; it is ~0.3 in a giraffe vs. ~1.0 in a horse. EMA tends to be larger in larger mammals, up to horse-sized, then it gets weird in really big animals.

We also scienced the hell out of salamanders. Four papers, all involving Fire salamanders Salamandra salamandra! Three stemmed from my past PhD student Eva Herbst’s work: one explaining a new method to measure joint mobility; another applying that to walking salamanders in vivo and ex vivo; and the third comparing similar data to the Permian ‘giant’ salamander-relative Eryops, showing that its hip and knee joints were about as mobile as a Fire salamander’s. The fourth paper used video analyses of Fire salamanders in a theoretical model and simulation (with other animals) to demonstrate how multi-legged locomotion is controlled. It’s great to have these studies (partly from my old NERC grant on tetrapod locomotor evolution) out after ?5+ years; now Fire salamanders are among the salamanders whose locomotion we understand best. And we have more data still…

Above: Hindlimb configurations in S. salamandra (A) from rotoscoping of in vivo walking, during (B) mid-swing, (C) toe-on,(D) mid-stance, and (E) just before toe-off. These limb configurations were recreated in E. megacephalus (F) with three different knee spacing options: (G–J) tight knee spacing; (K–N) intermediate knee spacing; and (O–R) larger knee spacing, based on the amount of knee spacing present in the rotoscoped salamander at the null pose. S. salamandra configurations in (B–E) were scaled to E. megacephalus knee B.

Oh and I did some science consulting! “Prehistoric Planet” rocked the casbah; glad to see it out ~3 years after I began offering some critiques on the animations. I hope one scene I commented on eventually sees the light of day, as it wasn’t in the final programme. Similarly, “Dinosaurs: The Final Day” did well, and I gave the same kind of input. My experiences with these shows have inspired me to blog someday about how to become, and do, science consulting for documentaries, so watch for that. I may work in some commentary on what it means to be an invisible minority in that context, as I have thoughts.

Blink and you’ll miss me waving my arms about how Carnotaurus might have waved its arms!

There’s a lot of fun science to come, and that keeps me going. We’ve finished initial biomechanical models of 13 extinct archosaurs for DAWNDINOS, and those will become papers on modelling and simulating locomotor function, ultimately testing how performance differed between Pseudosuchia and Dinosauriformes/Dinosauria; and how locomotion evolved (e.g., bipedalism). Some examples in progress are below; these don’t show the muscles or external dimensions reconstructed. Stay tuned in 2022 and beyond for all that! Beyond this, time will tell what I’ll be doing, but DAWNDINOS is going to keep me very busy for plenty of years, and that is good fun for me.

Top image: top to bottom = Postosuchus (pseudosuchian), Heterodontosaurus (ornithischian dinosaur), Riojasuchus (pseudosuchian), Silesaurus (dinosauriform); Bottom image: Gracilisuchus (pseudosuchian), Lago/Marasuchus (dinosauriform), Coelophysis (theropod dinosaur). These are from ongoing studies with DAWNDINOS team members and collaborators around the world. All use 3D scans of the actual fossil material of one main specimen, wherever possible.

See you in 2023!?

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I’ve been reluctant to write this post as it meant confronting dark times that I continue to be immersed in with the rest of the world. When I last wrote an “annual” summary, it was exactly when I was leaving my office for “just a few weeks or months” of remote working away from the COVID-19 pandemic. Cue ironic laughter.

Stomach-Churning Rating: unclassifiable due to COVID-19 insanity

In terms of my normal blog-summarizing activities, my job here is easy: in >18 months I’ve managed 3 posts: 1 by a guest, on stylophoran echinoderms; and 2 about papers (dino leg muscle leverage; and predictive simulations using such) related to the DAWNDINOS project my team has been focusing on for 5 years now. But normal is dead and gone.

What I should write about is what the experience since March 2020 has been like for me. I can try, briefly. Much I am not willing to delve into publicly. I struggled, and suffered; not so directly but indirectly, and from personal issues unrelated to the pandemic, too. I didn’t deal well with the isolation, the boredom and profound ennui, the mass confusion, the under-exercise and over-snacking, the repetition, the anxiety, the uncertainty, the excessive screen time (Netflix! Zoom!), the retooling of teaching for “blended learning” online, the sometimes overly risk-averse bureaucracy that spiralled out of control, the horrifically ugly selfish underbelly of society laid so bare along with smirking racism and other forms of xenophobia (see: Brexit), the endless bad news, the fury I felt at government officials and other (cov)idiots, the feeling of being trapped in my home office and my body; and trapped in a world with political/social machinery that can feel hopelessly broken. I thrive off the novelty and excitement of travel, and without it I withered. These things wore me down to a numb husk and I’m not much better, but am trying to build my energy back so I can pick some battles to make improvements. On top of that, there were tragedies in my life (deaths of two beloved cats; one fairly swiftly from cancer at a young age, one very slowly from old age and related disease), and other awful personal things. I didn’t lose anyone close to me to COVID-19, but I knew lots of people who got infected. Especially in summer 2020 and winter 2020-21, it felt like the punches just kept coming. There’s no way I can describe it all adequately; neither in person nor on this blog. It seems like a lot of people feel that way, but each in our own private way.

I lost a friend in 2020: Prof. Jenny Clack FRS. I’ve not been able to really come to grips with that, even though there was fair warning. Processing grief is on a slow timetable. We had some great times ~2009-2020 working on fossil tetrapods together. I miss her big smiles and our talks about the latest fossil tetrapod news whenever I visited Cambridge. It is hard for me to write more than that right now; I am so drained by the past >18 months. We’ve been served a buffet of flavours of loss to lament.

from this obituary in Nature

There’s hope on the horizon, I think, so I cling to that. And we got two new kittens at home, who are simply a joy, and we’ve been clinging to each other. Many cuddles.

It feels very strange, and privileged, to say that work (even though stuck at home) has been a happier thing for me amidst it all. Even that hasn’t been easy, but it has sometimes been a welcome refuge or distraction. I’ve been able to do some real “hands-on” (computer-based) research for long periods, gained skills, and it felt great to be a “real scientist”; not just a manager of scientists; in that regard. I learned a lot about my team’s DAWNDINOS project… and how I’d do it all so differently if I could begin again. At least I have these lessons going forwards. A 5-year, sole-PI, £2.1M project will teach you much about project management. It was so far beyond anything I’d ever tried before. I’m proud of what we’ve achieved now, such as the paper linked above and what’s coming up as the project sadly draws to a close at the end of March 2022. I feel like we’ll be justified to thumb our noses at a few armchair critics, snide naysayers, and cynics, or at least feel personally satisfied even though we’ll never satisfy everyone with our project’s outcomes vs. what certainly were ambitious goals and risks. And I have plans to move on while keeping one foot firmly planted on the foundation we’ve built…

Other than that, I’ve barely touched a work-related freezer since March 2020 and have done no research-related dissections; only digital form and function for me, I’m afraid. That’s OK though. We are slowly migrating back to a bit of in-person working now, and there are some brief dissections and other hands-on work needed as undergrad/Masters research projects begin. I look forward to that.

I was interviewed for two articles about life in science that are meaningful to me: this one on disability pride month, and this one on “advice to my younger self“. Check them out if you haven’t yet?

And that’s all I can say for >18 months in which time has been such a slow grind, warped by the pandemic and the rest of my world.

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The blog is back! Briefly. With dinosaurs. Back in 2005, I published a paper in which I used a “SIMM” 3D musculoskeletal biomechanical model of Tyrannosaurus rex to analyse its muscle actions and infer a relatively upright hindlimb pose. This was an outcome from my NSF-funded postdoctoral research at Stanford University, in which engineers kindly taught me how to use SIMM (handing me a loaded gun?). Part of my plan all along was to build multiple such models along a rough evolutionary sequence to revisit old questions I had with past, qualitative functional morphology papers from 2000 onwards, and see if biomechanics could quantitatively reveal more about the functional evolution of dinosaur hindlimb muscles. So I got data for modelling some extinct dinosaurs (theropods Dilophosaurus, Allosaurus, Velociraptor) and living birds (Struthio, others) and published nuggets of that but held others back…

Stomach-Churning Rating: -1/10; dinosaurs!

I handed these 3D model data off to my PhD student Vivian Allen in ~2007, charging him with the task of making more models to flesh out the phylogeny and finish what I’d started. And he sure did. He graduated, did a couple of postdocs with me, and we gradually massaged his thesis chapter on this topic into a draft paper. Easier said than done, though! That’s why 14 more years have passed.

Viv came up with some clever tools in MATLAB software code (from which he became a very competent programmer and went on to a successful career in that!) to boil complex data on muscle leverages (moment arms) across a wide range of joint motion for the hindlimbs for each taxon.

These data then were fed into further code that took the results from all models, ultimately 13 of them from an Australian freshwater crocodile to two living birds and 10 extinct dinosaurs plus close cousin Mara/Lagosuchus (Figure 1). The code expressed these leverages as changes in ancestral values along the main branch of the evolutionary tree from early (Triassic) “ruling reptile” Archosauria (represented here just by the croc as a proxy) to modern birds, and 9 main ancestral “nodes” in between. Our code tracked both how each of 35 hindlimb muscles we modelled evolved in its leverage, as well as overall “average” leverage of functional groups around the hip, knee and ankle joints.

So, back and forth we went for some 10 years playing with the models (see Video below), data and code, and the paper describing the whole thing, slowly closing in on a final version but also sometimes distracted by our other projects and Real Life Stuff like health and children, and concerns about how we conducted this study (i.e. a lot of fiddling).

Figure 1: Evolutionary tree of dinosaurs and their relatives as used in the study, showing all 13 models, species names, and names of groups along the bottom (red nodes) of the tree. Averostra and Avetheropoda were ancestral groups of theropod dinosaurs that the study inferred had particular specialisations of the hindlimb muscles. Right hindlimbs in side view. The limbs are all straightened vertically into a baseline reference posture but the study investigated variation in muscle function across a wide range of limb poses.

Then I got a new grant “DAWNDINOS” that changed the scene for me, refocusing my team’s energies onto the Triassic (and early Jurassic) and the evolutionary biomechanics of diverse archosaurs’ locomotion, assessed with both LOTS of experimental studies of living crocs and birds, and LOTS of predictive simulations of locomotion. Stay tuned for much more on that from our team, but we’ve already published some key steps here. Most notably, we developed an improved protocol for modelling and simulating our animals, as shown by Bishop et al.’s 2021 study of the early theropod Coelophysis bauri (also appearing in the current paper). Awkwardly for me, that new method rendered our old models and methods a bit obsolete (although still fine), so I pushed to publish this current paper with Viv, and brought collaborator Dr. Brandon Kilbourne on board to aid in some final stats, figures and more. That finally did it, and now we’ve published the paper in Science Advances. Deep breath.

Video: Rotating movies of 3 musculoskeletal models from this study. Models have been posed into representative limb orientations illustrating a gradual or stepwise transformation from more upright to more crouched.

Well what’s the paper about, then? We used our 13 models and processed evolutionary functional patterns to test three main questions (hypotheses) about muscle leverage, making educated guesses at what might prevail from early Archosauria to Aves:

  1. Hip extensor / flexor (i.e. femur retractor/protractor) moment arm ratios remained constant. We weren’t sure what to expect, as these antagonists both seem to change a lot on the whole lineage, so we went with this prediction.
  2. Knee flexor / extensor ratios decreased; i.e. the flexors (“hamstrings” etc.) weakened and/or extensors (equivalent of our quadriceps) strengthened their leverage. Anatomy of the knee joint and muscles around it suggests this, plus since Gatesy’s 1990-onwards studies we’ve expected archosaurs to shift from more ‘hip-based’ to more ‘knee-based’ locomotion as we get closer to avian ancestry.
  3. Hip medial (internal) long-axis rotator / abductor (i.e. pronators of the limb vs. those that draw the leg away from the body) ratios increased. This idea comes right from my paper w/Gatesy in 2000, where we surmised that archosaurs shifted from relying on hip adductors (in crocs/other quadrupeds) to abductors (in bipedal dinosaurs; like humans) to medial rotators (‘torsional control’ as in birds today) during weight support.

Moreover, we reconstructed the evolution of 35 muscles’ actions across ~250 million years, which was a new step.

Here’s a summary of what we found (Figure 2):

Figure 2: Short visualization/explanation of the study’s main insights. Pictures by palaeoartist Jaime Headden: https://qilong.wordpress.com/about/ in left side view, including “muscled” and silhouette images. Right side images include representative hip, knee and ankle muscles from the study. Changes such as the enlargement of muscles in front of the hip that straighten the knee, and reduction of the caudofemoralis longus muscle that runs from the tail to the back of the thigh, are evident.

So, overall hypothesis 1 about hip extensors/flexors ended up complicated; rejected because hip flexor leverage actually increased. Furthermore, we found that around the ancestral nodes for early theropod dinosaurs (Neotheropda through Avetheropoda; around 200 Mya), there were peaks in muscle leverage (size-normalized) that surprised us, and persisted despite many different analyses we threw at them over the years. As far as we could tell, these peaks that kept appearing for various muscles’ actions were “real” (estimates). Which meant these ancestors may have had specialised high leverage relative to both their own ancestors and descendants; the peaks got reversed in evolution. These ancestors had some other weird anatomical and functional traits, such as tightly articulated hip joints early on (which they lost later), increased body size in the later forms, more ‘macropredatory’ ecology (e.g. eating sauropods?), and a centre of mass of the body that was shifted forwards (due to big arms and heads/necks). This weirdness is a cool unexpected finding that showed up for the other hypotheses too, and it needs some more investigating. A ‘failed’ hypothesis test led to neat insights.

Figure 3. From the paper– showing our main results for changes in moment arm ratios across archosaurian ancestors. Hip extensors/flexors decreased then increased; knee flexors/extensors decreased; and hip medial rotators/abductors decreased then had a series of increases.

Hypotheses 2 and 3 found good support, on the contrary, overall (Figure 3). We seem to have been able to quantify the shifts from hip-based to knee-based, and abductor-based to medial-rotator-based, muscle actions. I find that very satisfying. Ankle weight support (extension) capacity also increased, which fits morphological changes fairly well. If you’re into archosaur limb muscle form and function, there’s a lot more food for thought in the paper.

Funnily enough, ~20 years has been sufficient time that we could have had plenty more models in this study if we’d delayed it even longer and re-re-re-analysed our data. But we had to draw the line somewhere and not infinitely revise with every new model we’ve been creating. With the current state of musculoskeletal modelling in my group, we could have more than doubled our sample size and fleshed out the most important gaps such as in the crocodile-lineage (extinct Pseudosuchia) and other Triassic forms plus elsewhere. A big challenge remains having some nice 3D-preserved early fossil birds beyond Archaeopteryx; e.g. so many nice Chinese ones are too flat (e.g. joints we need) to reliably model here. It’s something that can still be done and is worth doing, but I suspect the general trends we’ve found along the dinosaur lineage are “correct”.

What’s personally important to me about this paper is (1) how it not only bridges a huge morphofunctional gap across archosaur evolution in scientific terms, and (2) how we’ve completed a long-delayed project with stubbornness (and during a pandemic!), but also (3) how it bridges my past career from my PhD and postdoc to the present work with DAWNDINOS. We’re now forging well beyond what this new paper has done in terms of truly testing, as best we can (estimate) so far, how limb muscles of archosaurs functioned and evolved, and how these contributed to particular behaviours and performance (maybe even palaeoecology and evolutionary success/extinction?). The current paper is just simple modelling of muscle leverage, but leverage is only one (very important!) piece of muscle function and performance. With fully dynamic, anatomically integrative, physiologically and physically representative biomechanical computer simulations that predict what living and extinct archosaurs could or could not do, we can do even better. So watch for that! Hopefully it won’t all take 20 years, or 250 million.

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Today is the 210th anniversary of Charles R. Darwin’s birthday so I put together a quick post. I’d been meaning to blog about some of our latest scientific papers, so I chose those that had an explicit evolutionary theme, which I hope Chuck would like. Here they are, each with a purty picture and a short explainer blurb! Also please check out Anatomy To You’s post by Katrina van Grouw on Darwin’s fancy pigeons.

Stomach-Churning Rating: 1/10 science!

First, Brandon Kilbourne at the Naturkunde Museum in Berlin kindly invited me to assist in a paper from his German fellowship studying mustelid mammals (otters, weasels, wolverines, badgers, etc.; stinky smaller carnivorous mammals). Here we (very much driven by Brandon; I was along for the ride) didn’t just look at how forelimb bone shape changes with body size in this ecologically diverse group. We already knew bigger mustelids would have more robust bones, although it was cool to see how swimming-adapted and digging-adapted mustelids evolved similarly robust bones; whereas climbing ones had the skinniest bones.

The really exciting and novel (yes I am using that much-abused word!) aspect of the paper is that Brandon conjured some sorcery with the latest methods for analysing evolutionary trends, to test how forelimb bone shapes evolved. Was their pattern of evolution mostly a leisurely “random walk” or were there early bursts of shape innovation in the mustelid tree of life, or did shape evolve toward one or more optimal shapes (e.g. suited to ecology/habitat)? We found that the most likely pattern involved multiple rates of evolution and/or optima, rather than a single regime. And it was fascinating to see that the patterns of internal shape change deviated from external shape change such as bone lengths: so perhaps selection sometimes works independently at many levels of bone morphology?

Various evolutionary models applied to the phylogeny of mustelids.

Then there, coincidentally, was another paper originating in part from the same museum group in Berlin. This one I’d been involved in as a co-investigator (author) on a Volkswagen (yes! They like science) grant back about 8 years ago and since. There is an amazing ~290 million year old fossil near-amniote (more terrestrial tetrapod) called Orobates pabsti, preserved with good skeletal material but also sets of footprints that match bones very well, allowing a rare match of the two down to this species level. John Nyakatura’s team had 3D modelled this animal before, so we set out to use digital techniques to test how it did, or did not, move—similar to what I’d tried before with Tyrannosaurus, Ichthyostega and so forth. The main question was whether Orobates moved in a more “ancestral” salamander-like way, a more “derived” lizard-like way (i.e. amniote-ish), or something else.

The approach was like a science sledgehammer: we combined experimental studies of 4 living tetrapods (to approximate “rules” of various sprawling gaits), a digital marionette of Orobates (to assess how well its skeleton stayed articulated in various motions), and two robotics analysis (led by robotics guru Auke Ijspeert and his amazing team): a physical robot version “OroBOT” (as a real-world test of our methods), and a biomechanical simulation of OroBOT (to estimate hard-to-measure things in the other analyses, and matches of motions to footprints). And, best of all, we made it all transparent: you can go play with our interactive website, which I still find very fun to explore, and test what motion patterns do or do not work best for Orobates. We concluded that a more amniote-like set of motions was most plausible, which means such motions might have first evolved outside of amniotes.

OroBOT in tha house!

You may remember Crassigyrinus, the early tetrapod, from a prior post on Anatomy To You. My PhD student Eva Herbst finished her anatomical study of the best fossils we could fit into a microCT-scanner and found some neat new details about the “tadpole from hell”. Buried in the rocky matrix were previously unrecognized bones: vertebrae (pleurocentra; the smaller nubbins of what may be “rhachitomous” bipartite classic tetrapod/omorph structure), ribs (from broad thoracic ones to thin rear ones), pelvic (pubis; lower front), and numerous limb bones. One interesting trait we noticed was that the metatarsals (“sole bones” of the foot) were not symmetrical from left-to-right across each bone, as shown below. Such asymmetry was previously used to infer that some early tetrapods were terrestrial, yet Crassigyrinus was uncontroversially aquatic, so what’s up with that? Maybe this asymmetry is a “hangover” from more terrestrial ancestry, or maybe these bones get asymmetrical for non-terrestrial reasons.

The oddly asymmetrical metatarsals of Crassigyrinus.

Finally, Dr. Peter Bishop finished his PhD at Griffith University in Australia and came to join us as a DAWNDINOS postdoc. He blasted out three of his thesis chapters (starting here) with me and many others as coauthors, all three papers building on a major theme: how does the inner bone structure (spongy or cancellous bone) relate to hindlimb function in theropod dinosaurs (including birds) and how did that evolve? Might it tell us something about how leg posture or even gait evolved? There are big theories in “mechanobiology” variously named Wolff’s Law or the Trajectorial Theory that explain why, at certain levels, bony struts tend to align themselves to help resist certain stresses, and thus their alignment can be “read” to indicate stresses. Sometimes. It’s complicated!

Undaunted, Peter measured a bunch of theropod limb bones’ inner geometry and found consistent differences in how the “tracts” of bony struts, mainly around joints, were oriented. He then built a biomechanical model of a chicken to test if the loads that muscles placed on the joints incurred stresses that matched the tracts’ orientations. Hmm, they did! Then, with renewed confidence that we can use this in the fossil record to infer approximate limb postures, Peter scanned and modelled a less birdlike Daspletosaurus (smaller tyrannosaur) and more birdlike “Troodon” (now Stenonychosaurus; long story). Nicely fitting many other studies’ conclusions, Peter found that the tyrannosaur had a more straightened hindlimb whereas the troodontid had a more crouched hindlimb; intermediate between the tyrannosaur and chicken. Voila! More evidence for a gradual evolution of leg posture across Mesozoic-theropods-into-modern-birds. That’s nice.

Three theropods, three best-supported postures based on cancellous bone architecture.

If you are still thirsty for more papers even if they are less evolutionary, here’s the quick scoop on ones I’ve neglected until now:

(1) Former PhD student Chris Basu published his thesis work w/us on measuring giraffe walking dynamics with force plates, finding that they move mostly like other quadrupeds and their wobbly necks might cost them a little.

(2) Oh, and Chris’s second paper just came out as I was writing this! We measured faster giraffe gaits in the wilds of South Africa, as zoo giraffes couldn’t safely do them. And we found they don’t normally go airborne, just using a rotary gallop (not trot, pace or canter); unlike some other mammals. Stay tuned: next we get evolutionary with this project!

(2) How do you safely anaesthetize a Nile crocodile? There’s now a rigorous protocol (from our DAWNDINOS work).

(3) Kickstarting my broad interest in how animals do “extreme” non-locomotor motions, we simulated how greyhounds stand up, finding that even without stretchy tendons they should, barely, be able to do it, which is neat. Expect much more about this from us in due time.

(4) Let’s simulate some more biomechanics! Ashley Heers, an NSF research fellow w/me for a year, simulated how growing chukar birds use their wing muscles to flap their way up steeper inclines (“WAIR” for devotees), and the results were very encouraging for simulating this behaviour in more detail (e.g. tendons seem to matter a lot) and even in fossil species; and finally…

(5) Hey did you ever think about how bone shape differs between hopping marsupials (macropods) and galloping artiodactyl (even-toed) mammals? We did, in long-the-making work from an old BBSRC grant with Michael Doube et al., and one cool thing is that they mostly don’t change shape with body size that differently, even though one is more bipedal at faster speeds—so maybe it is lower-intensity, slower behaviours that (sometimes?) influence bone shape more?

So there you have the skinny on what we’ve been up to lately, messing around with evolution, biomechanics and morphology.

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I’m a few months late on the six-year anniversary of this blog but finally found some time. (For year 5 go here) It was seemed to be another quiet year on the blog because it was not a quiet year for work or other aspects of life. The DAWNDINOS project got into full swing and there will be a lot more about that soon on that website and maybe here, too.

Freeezersaurus 2 has been mostly vacated now; and Freezersaurus 3 is in place, with the contents shifted– and a mad rush in action to get rid of (boil down + varnish bones of) as many specimens as I can! I have way too many… of course, mostly elephant bits. Here are the last big bits left in Freezersaurus 2; we are intimidated to move them…

Stomach-Churning Rating: 3/10 until the opossum-digested-by-gator at the end, then 9/10, so hang tight!

Year 6 began with a post about a new paper! We published a big synthesis of data on what mammals turn their kneecaps into bone (or not), and how those states evolved. The story turned out pretty interesting and we are still pursuing some angles that it inspired, so stay tuned! Otherwise, the kneecap project (i.e. Leverhulme grant) has ended and staff/students have moved on (but published all their papers on it– well done, Sophie, Kyle and Viv!!), so it will fall quiet on that topic for a while.

Then we published another paper, and it happened to involve more sesamoid-y stuff! But with birds and their ankles, and some tantalizing evidence of soft tissue and organic biomolecular preservation. I’m still a bit amazed this paper happened and am pleased we got to collaborate on it.

Next, I got to ramble on a bit, about another serious topic related to science– this time, on blame.  I had forgotten about that post, and now on re-reading it it has fresh new relevance to me. All the more reason to keep blogging!

Smaller but better: Freezersaurus 3, part of a proud dynasty!

But then, what do you know, we published another kneecap paper! And on ostriches! With some simple but ambitious finite element analysis. We are meaning to get back to this approach… it just scratched the surface of some super cool “mechanobiology” that could shed light on “evo-devo”.

And next, BOOM! The dinosaurs dawned. By which I mean my current ERC grant “DAWNDINOS” began. Do take a look– the website now has some lovely NEW palaeo-art by Bob Nicholls, John Conway and Scott Hartman, with more to come! This project’s inception led to an inspection of caeca in tinamous; the following post.

I managed to have some summer holiday in the midst of the year, and that made an extremely memorable “pilgrimage” to a fossil site possible– “Experiencing the Irish Tetrapod Tracks” was the blog post that emerged from the waters. (That post needs a little revamp in light of some other literature; I will get around to that soon)

DAWNDINOS got a nice new 3D printer and we’re gradually printing up some archosaurs to show.

Holiday ended and back to the freezer I went, to post about how we thaw specimens (and how odd wallaby legs can be). Then we published three papers in quick succession and I played catchup posting about them (Mussaurus forelimbs; mouse vs. human hindlimb simulations; and tetrapod forelimb musculature).

Speaking of mouse hindlimb simulations, I didn’t blog about this related paper that we published earlier in 2018, but it’s very relevant. And GIF-worthy!

But I couldn’t stay away from bird legs for long, and so soon enough I posted “The Bird Knee Challenge“, which still stands.

Jumbo the elephant loomed into view at Christmas-time (plus a documentary about T. rex with Chris Packham, and another about Hannibal’s elephant excursion over the Alps– the latter also playing on PBS in USA); all featuring cameos with me, so I posted about the Jumbo/Attenborough one. That’s another life experience I will treasure.

Next, back to musing about science and humanity– and who’s a more big-name, very relatable human scientist than Darwin? Well, we could debate that endlessly but I posted about Darwin’s human nature for Darwin Day.

That takes me through to March 2017. I’ve posted a little more since then but that counts as Year 7 of this blog, so we’ll catch up with that then. Looking back on ~2017, I posted more blog posts than I thought I did! Maybe it’s just that 2018 feels very quiet to me blog-wise. We’ll see how it shapes up though.

Years ago, my team dissected an alligator (for Allen et al. 2010,2014 papers if you are keeping track) that had an opposum in its stomach, during winter when feeding wasn’t supposed to be happening much. So that came up again this year; and hopefully it does not make anything come up from your stomach. But this is real anatomy in action.

 

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‘Full fathom five thy father lies, of his bones are coral made. Those are pearls that were his eyes. Nothing of him that doth fade, but doth suffer a sea-change into something rich and strange.’

(Shakespeare’s The Tempest Act 1, Scene 2)

Stomach-Churning Rating: 1/10- this time, tame images.

Five years have passed on this blog now, and this year with them passed Freezersaurus (soon to leave RVC’s campus; sob!). Indeed, the blog has changed, via the tempests I’ve weathered in my own life, which I lamented in last year’s summary. Regardless, the blog has been visited this year more than in any prior year, with >101,000 visits– thanks!

This year I’ll keep my annual retrospective shorter than usual, as I’m feeling healthier and more energetic but less self-indulgent.

I still got to have fun, like this ComicCon in NOLA. So, some self-indulgence.

I still got to have fun, like this ComicCon in NOLA. So, some self-indulgence.

I began the past year by blogging about why I blog, and how I feel that in a way I (and others) have long been blogging even if it wasn’t called that, and how I don’t see science communication such as blogging or tweeting as something distinct from science itself. Reading back on that post, I find some themes there that emerge again and again throughout this year’s posts, such as valuing diversity (in its diverse forms) and curiosity.

Like this? So much more is here!

Like this you do? So much more here there is!

Never tired of elephant feet will I be!

Those introspective posts included one that is very close to my heart, about how I notice my own decline (some of it since reversed, but some still lingering) and feel grief. It wasn’t long after that post that I wrote more about my experience as an epileptic; what it’s like to have a seizure. Another, more science-focused (but still very human) one laid out my views on what my team’s principles are. Then I returned a few posts later with some reflection on how time passes (too quickly!) and with it come publications (I reviewed some of my team’s latest), among other changes as a person living as an academic. I wrote then that “I suspect I’ll look back on 2016 and see it as transformative, but it hasn’t been an easy year either, to say the least.” Yep. Spot on. I’ve started a big new grant which has been a huge challenge, and I’ve rediscovered my health and some of my old self with it, rekindling some passion and hope. Later, on USA’s Thanksgiving, I typed in some musings about my appreciation for diversity in the human world. Again, with thoughts of disturbing recent political/social trends weighing heavily on me, I celebrated how the Women’s March inspired me, and how that relates to the importance of curiosity and empathy.

He ain't goin' nowhere.

He ain’t goin’ nowhere.

But there was plenty of time here to talk about freezers and anatomy and research, too! We published a paper that I think I’ll long regard as one of our better ones, on using dynamic computer simulations to study how ostriches control their walking and running gaits with their muscles. Throughout 2016, we worked hard to get our anatomical research out there to the public in person. So I posted about our presentations at the Cheltenham Science Festival (including a public cheetah dissection, which was a huge hit!), and “Team Cat” did a dissection of another cheetah (all zoo mortalities) at the RVC for a well-attended joint event with UCL/Grant Museum on “Wild Cats Uncovered: movement evolves“. UCL’s PhD student (soon Dr.) Marcela Randau wrote a great guest post about our paper on how size and ecology relate to the shapes of backbones in cats, which tied in nicely with those big cat dissection presentations. I also ruminated about how scientists balance testing big questions vs. getting very accurate data, using the big question (in my and others’ research) about how much more slowly big animals can move relative to smaller ones as an example. As a final anatomical post this blog-year, I wrote about the biceps muscle, and people seemed to like that, so I will do more of those.

Whale humeral epiphysis (joint) turned into a sculpture with walrus ivory teeth, at Point Vicente Museum, LA.

Whale humeral epiphysis (joint) turned into a sculpture with walrus ivory teeth, at Point Vicente Museum, LA.

In addition to being open about my (and my team’s) thoughts, experiences, dissections and publications, we put a lot of effort this year into making our scientific and anatomical data public. My blog posts about our huuuuuge open datasets on crocodile and tuatara 3D scans exemplify a deluge of data that is going to keep coming out. We’re going to push very hard on this, including an effort to release old data from prior publications of mine. I’m thrilled that we can finally deliver on these things; it is a great feeling!

Yale Peabody Museum specimen YPM57100: ilium (hip bone) and vertebrae of the Triassic archosaur Poposaurus. More about this later!

Yale Peabody Museum specimen YPM57100: right ilium (hip bone) and vertebrae of the Triassic archosaur Poposaurus. More about this later!

We enter year 6 of this blog with a new (temporary, maybe) freezer, which we failed to reach a conclusion on naming. I’m sure you’re on tenterhooks awaiting the final decision. I have a bunch of ideas for some blog posts to come soon (really fun anatomical papers en route), and I always welcome guest posts so let me know if you want to do one! In the meantime, I sprinkled some images from my 2016-7 travels here in this post. With good health comes more ability to go do fun things that I’ve put off while recovering, so hopefully 2017-8 will provide some new images to share.

A sunny Sceloporus fence lizard seen in LA.

A sunny Sceloporus fence lizard seen in LA. Meanwhile, the UK awaits some sunshine…

I doth not protest too much, methinks– there have been some good times this past year, and ides of March be damned, I look forward to sharing more science here for year 6!

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And I post my blog and stare
Into x-rays of an ostrich
I’ve always known that radiographs never lie
People always say “that’s cool”
To see x-rays of an ostrich
So keen to know what
Lies behind the skin

(evolved from “Eyes of A Stranger” by Queensrÿche, from the epic masterpiece of Operation: Mindcrime (1988). One of my favourite albums of all time, and a fantastic concept album too. The band was operating at their peak. Tight! Drug addict Nikki gets brainwashed by the evil Dr. X and made to assassinate a nun, Sister Mary, who was a prostitute, and then there’s like a revolution or something, and things get all screwed up and no one ends up happy – or alive. All the while, Geoff Tate is singing his guts out. Anyway, I got to see them play the whole album live in 1990 in Madison, WI, for the filming of Operation: Livecrime, which was like a Mecca moment for me back then. Look for me (pre-bald years) in about the 6th row. )

What does that album have to do with the number 2 (two days left in Freezermas)? Hmm… Track 2 is the instrumental Anarchy-X, and today’s post is about X-rays as well as that funky ostrich (2 legs good! 2 toes good, too!) again, so I’m satisfied, and by this point you’re probably just oggling the mind-blowing images below anyway, so fuck it!

Stomach-Churning Rating: 2/10; just X-rays.

Tech/MRes Kyle Chadwick, Renate Weller and the equine imaging team at the RVC took these x-rays of our birdie for us and for an artist who is doing a big x-ray animal art show (more news on this soon!)– thanks to all of them for some truly awesome images! I could stare at the intricate details in these images for hours– go ahead, do it. Click to emostrichinate them (this post needs to be viewed on nice big screen), and oggle away…

Head and neck.

Head and neck.

Another view of the same.

Another view of the same. The highly flexible esophagus and trachea can be seen going diagonally across the neck; twisting from ventral to dorsal. It’s floppy, so it can do that.

Neck near the head; tapering.

Neck near the head; tapering.

Middle of neck. Check out the rings of the trachea!

Middle of neck. Check out the rings of the trachea!

Base of neck and shoulder

Base of neck and shoulder.

Shoulder and chest. Hard to image; thick and dense (still was frozen).

Shoulder and chest. Hard to image; thick and dense (still was frozen), hence the whiteout toward the left side of the image.

Check out that wing!!

Check out that wing!!

Ankle- note the big calloused pad that ostriches rest on (right side of image).

Ankle- note the big calloused pad that ostriches rest on (right side of image).

That two-toed foot... but did you know that normally the missing 2nd toe is still there as a fibrous remnant on the 3rd toe?

That two-toed foot… but did you know that normally the missing 2nd toe is still there as a fibrous remnant on the 3rd toe?

Tomorrow: the final day of Freezermas. What will it be?

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Sick feet, pig feet, boo hoo, in pain you are
Not well heeled; fate sealed, oh no, inflamed they are
And when your trotter’s on the floor
You’re nearly a good boar
Almost a porker

(corrupted from Pink Floyd’s “Pigs (Three Different Ones)” track #3 from the Animals concept album (1977). A song with quite a history- check out some more about it.)

It could happen...

It could happen…

Concept albums often weave back and forth between themes in a non-linear story, returning to refrains and leitmotifs to create their narrative weft and warp. This Freezermas, I’ve already woven in two legs and four legs, cats and other beasts, x-rays and more. Today, I tie in another thread, which extends throughout the blog, but especially into yesterday’s post. This post is about feet and health again. But it is also solely about pigs, which are cool animals whose biomechanics are surprisingly little studied.

It’s a shorter post (in contrast to the 11-17 minute Pink Floyd cousin song); a drum solo if you will; with just three images representing three big pigs and their funky feats of footedness, and the three days left in Freezermas. One image is about ongoing research; the other two about bizarre cases that kinda freak me out (enough to want to know more about them).

Stomach-Churning Rating: 4/10, not for gore but for surreality; things that should not be. Especially the 2nd picture.

pig gif

Above: X-ray GIF (may take a while to load) from our 3D XROMM analyses of foot biomechanics, here showing a pig studied by Dr. Olga Panagiotopoulou (also RVC Fellow Jeff Rankin; and Prof. Steve Gatesy at Brown University). With data like these, we not only can measure how the tiny bones move, but also get better estimates of the loads on the soft tissues within those feet. Those loads should relate to the risks of musculoskeletal injury or disease. This GIF is just a teaser for some fantastic 3D images we’re producing. The pig’s feet were normal. The odd little spheres on them are skin-adhered markers that let us compare how external estimates of skeletal motion compare to actual motion; normally this is a big source of error.

I know little about this case, posted on Reddit (link here), except that the overgrown, grossly deformed toes/hooves of this pig are like nothing I've seen before! This almost gave me nightmares. Poor chicken-footed pig!

I know little about this case (seems to trace back to an original Brazilian news story), posted on Reddit (link here), except that the overgrown, grossly deformed toes/hooves of this pig are like nothing I’ve seen before! This almost gave me nightmares. Poor chicken-footed pig. Foot deformities of this kind in pigs don’t seem to be as much of a problem as in cattle or horses; from the limited literature I’ve seen on this, they seem to have more problems with the soft tissues of their feet, such as  abscesses or inflammation of the digital cushion (padding) of the trotter.

Another crazy case; but this one I was able to track down more about after reading the Reddit post here. The Getty images page says: This photo dated November 24, 2011 shows a Chinese farmer showing off his prize swine, which he named 'Strong Pig', as the disabled animal keeps its 30kgs of body suspended in midair, in Mengcheng, east China's Anhui province. The pig has become an internet sensation around China due to its ability to walk around balancing on its two front legs. TOPSHOTS CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images)

Another crazy case; but this one I was able to track down more about after reading the Reddit post here. This news image page says:
“This photo dated November 24, 2011 shows a Chinese farmer showing off his prize swine, which he named ‘Strong Pig’, as the disabled animal keeps its 30kgs of body suspended in midair, in Mengcheng, east China’s Anhui province. The pig has become an internet sensation around China due to its ability to walk around balancing on its two front legs. TOPSHOTS CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images)”

Bipedal pigs– two legs good again? I guess so. Well done, Strong Pig. Well done.

Bipedal ability in injured/deformed/spooked quadrupeds is not so unusual- in addition to trained macaques and rats that have been scientifically studied, there are plenty of examples out there on the internet of videos/GIFs of bipedal cats, dogs, and so on… Post your favourites below. Hooray for the marvelous plasticity of the locomotor system! As Pink Floyd famously wrote, “Any fool knows a dog needs a home, a shelter from bipedal pigs.” (or something like that)

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Why should you care
If you have to trim my hooves?
I’ve got to move with good feet
Or be put down fast.
I know I should trot
But my old vet she cares a lot.
And I’m still living on stone
Even though these feet won’t last.

(mutated from The Who, “Cut My Hair“, Quadrophenia… from the heyday of concept albums and grandiose rock!)

Talkin' bout my osteitis?

Talkin’ bout my osteitis

Day Four of Freezermas. Four posts to go. I can see through time… Hence the silly title for today’s concept album track. Quadrupedophilia did not have a good ring to it, anyway.

Stomach-Churning Rating: 4/10. Reasonably tame; bones and hooves. Some pathologies of those, but not gory.

If Quadrophenia was the story of a man with four personalities (metaphor for the four band members), then quadrupedopheniaphilia is the story of how diverse forms of four-legged animals have lots of problems because of our exploitation of them, which leaves a crisis to resolve: Who are we? Are we caring enough to fix a bad situation we’ve created for our four-legged ungulate comrades?

Four legs good, two legs bad? Not really. I featured ostriches earlier this week and two legs are indeed pretty good. Four-legged cats are great, too. But four-footed big beasties with deformed hooves: those are bad all around. That leads to today’s topic…

But hey, happy 205th funkin’ birthday Charles freakin’ Robert Darwin!

Charles Darwin on his horse “Tommy” in 1868- from the Darwin Correspondence Project, https://www.darwinproject.ac.uk/darwins-photographic-portraits

Today’s post concerns a phenomenon that (Western) civilization has wrought with large hoofed mammals, and evolution is a big part of it (as well as biomechanics and anatomy) . Cynical perspective, with some truth to it: We’ve evolved larger and heavier animals to either do harder and harder work on tough surfaces like concrete floors and tarmac roads, or to stand around while we gawk at them or wait for them to get fat and tasty. Either way, the outcome should come as no surprise: their feet, the interface of that hard ground and their body, eventually start falling apart.

I’ve posted about this several times with respect to rhinos and elephants (here and here and here and here and here), but this post hits closer to home: what goes wrong with the humble hoof of our friend the horse, cow, sheep or other ungulate. It’s where the rubberkeratin hits the road. Ungulates have not evolved to live on dirty, wet concrete floors; to be obese and inactive; or to have hooves that don’t get worn down. So they suffer when they do encounter those modern conditions.

“No foot no horse,” they say, and it’s so true- once the feet start to go (due to hoof overgrowth or cracks, abscesses or other trouble), it’s hard to reverse the pathologies that ensue (arthritis, osteomyelitis, infections, fractures, etc.) and the animals start going lame, then other limbs (supporting greater loads than the affected limb) start to go, too, sometimes.

Jerry the obese, untrimmed-hoof-bearing horse.

Jerry the obese, untrimmed-hoof-bearing horse. “Turkish slippers” is an apt description. DM has more here.

We can do plenty about these problems, and the title track above explains one of them: trimming hooves. Hooves often get overgrown, and if animals are tame enough (requires training!) or are sedated (risky!), hoof care experts (farriers) can rasp/file/saw them down to a more acceptable conformation. If we don’t, and the animals don’t do the trimming themselves by digging or walking around or living on varied surfaces, then the feet can suffer. But there’s still not much evidence for most common species kept in captivity by humans that indicates what the best methods are for avoiding or fixing foot problems.

What we’ve been trying to do at the RVC is use our expertise in evolution, anatomy and biomechanics to find new ways to prevent, detect, monitor or reverse these foot problems. We had BBSRC grant funding from 2009-2012 to do this, and the work continues, as it behooves us to do… Past posts have described some of this research, which spun off into other benefits like re-discovering/illuminating the false sixth toes of elephants. We’re working with several zoos in the UK to apply some of the lessons we’re learning to their animals and management practices.

Above: Thunderous hoof impacts with nasty vibrations, and large forces concentrated on small areas, seem to contribute to foot problems in hoofed mammals. From our recent work published in PLOS ONE.

Foot health check on a white rhino at a UK zoo. Photo by Ann & Steve Toon, http://www.toonphoto.com/

Foot health check on a white rhino at a UK zoo; one of the animals we’ve worked with. Photo by Ann & Steve Toon, http://www.toonphoto.com/

If it works, it’s the most satisfying outcome my research will have ever had, and it will prevent my freezers from filling up with foot-influenced mortality victims.

Again, I’ll tell this tale mainly in photos. First, by showing some cool variations evolved in the feet of hoofed mammals (artiodactyls and perissodactyls; mostly even/odd-toed ungulates of the cow/sheep and horse lineages, respectively). Second, by showing some pretty amazing and shocking images of how “normal” hooves go all wonky.

Two ways to evolve a splayed hoof for crossing soft ground: 2 toes that are flexible and linked to big pads (camel), and 2 main toes that allow some extra support from 2 side toes when needed (elk). At Univ. Mus. Zoology- Cambridge.

Two ways to evolve a splayed hoof for crossing soft ground: 2 toes that are flexible and linked to big pads (camel), and 2 main toes that allow some extra support from 2 side toes when needed (elk). At Univ. Mus. Zoology- Cambridge.

Diversity of camelid foot forms: big clunky, soft Old World camel feet and dainty, sharp highland New World camelids.

Diversity of camelid foot forms: big clunky, soft Old World camel feet and dainty, sharp highland New World camelids. [Image source uncertain]

Moschus, Siberian musk deer with remarkable splayed hooves/claws; aiding it in crossing snowy or swampy ground. At Univ. Mus. Zoology- Cambridge.

Moschus, Siberian musk deer with remarkable splayed hooves/claws; aiding it in crossing snowy or swampy ground. At Univ. Mus. Zoology- Cambridge.

Tragulus, or mouse-deer, with freaky long "splint bones" (evolutionarily reduced sole bones or metatarsals) and dainty hooved feet. At Univ. Mus. Zoology- Cambridge.

Tragulus, or mouse-deer, with freaky long “splint bones” (evolutionarily reduced sole bones or metatarsals) and dainty hooved feet. At Univ. Mus. Zoology- Cambridge.

Overgrown giraffe hooves. An all-too-common problem, and one we're tacking with gusto lately, thanks to PhD student Chris Basu's NERC-funded giraffe project!

Overgrown giraffe hooves. An all-too-common problem, and one we’re tacking with gusto lately, thanks to PhD student Chris Basu’s NERC-funded giraffe project!

Wayyyyyyyyy overgrown hooves of a ?sheep, from the RVC's pathology collection.

Wayyyyyyyyy overgrown hooves of a ?sheep, from the RVC’s pathology collection.

Craaaaaaazy overgrown ?cow hooves, from the RVC's pathology collection.

Craaaaaaazy overgrown ?sheep hooves, from the RVC’s pathology collection.

If we understand how foot form, function and pathology relate in diverse living hoofed mammals, we can start to piece together how extinct ones lived and evolved- like this giant rhinoceros! At IVPP museum in Beijing.

If we understand how foot form, function and pathology relate in diverse living hoofed mammals, we can start to piece together how extinct ones lived and evolved- like this giant rhinoceros! At IVPP museum in Beijing.

So, what do we do now? If we love our diverse hoofed quadrupeds, we need to exert that quadrupedopheniaphilia and take better care of them. Finding out how to do that is where science comes in. I’d call that a bargain. The best hooves ever had?

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Freezermas continues with track 3 of our rockin’ anatomy concept album! The number of the beast today is 5 (five days to go in Freezermas!), and I will deviate from the rock/metal theme to embrace the other side of the tracks: hip hop and rap. The Beastie Boys and I go way back: their “Licensed to Ill” album was the second cassette tape I bought (I remember proudly showing it off in Geometry class, circa 1986/7), and still ranks as one of my favourite albums ever. Everyone should own a copy of that, and of this next album…

The Five Felids, featuring KC

If only MCA were still alive to do this follow-up album…

The Beastie Boys’ superb, old school rap NYC-style (and themed) “To The Five Boroughs” (2004) satisfies my search for a #5-themed concept album/song. No track has that title, so I’m going with this one, “Triple Trouble” (song 3; day 3 of Freezermas… c’mon this is all just an excuse for me to talk about music I like and celebrate the concept album/freezers anyway!), as an introduction to a collaborative cat (felid) project we’ve started; and to continue the felid theme from Sunday (also be sure to check out the Snow Leopard dissection I posted on earlier!):

If You If You 
Wanna Know Wanna Know 
The real deal about the cats
Well let me tell you 
We’re felid funded ya’ll 
We’re gonna bring you some mad facts

(yes, that’s painful, I know… be relieved, I tried working some rap jargon into this post’s text but it just looked wack)

Dodgy-looking bagged-up skinned jaguar (bag-uar?) after delivery from Scotland.

Dodgy-looking bagged-up skinned jaguar (bag-uar?) after delivery from Scotland.

Anjali Goswami at University College London, myself, and Stephanie Pierce have teamed up to join the former’s skills in mammalian evolution, morphometrics, evo-devo and more together with our RVC team’s talents in biomechanics, evolution and modelling, and to apply them to resolving some key questions in felid evolution. We’ve hired a great postdoc from Bristol’s PhD programme, soon-to-be-Dr. Andrew Cuff, to do a lot of the experimental/modelling work, and then we have the marvellous Marcela Randau as a PhD student to tackle more of the morphometrics/evo-devo questions, which we’ll then tie together, as our Leverhulme Trust grant’s abstract explains:

“In studying the evolution of vertebrate locomotion, the focus for centuries has been on limb evolution. Despite significant evolutionary and developmental correlations among the limbs, vertebrae, and girdles, no biomechanical studies have examined the entire postcranial skeleton or explicitly considered the genetic and developmental processes that underly morphological variation, which are captured in phenotypic correlations. We propose to conduct experimental and geometric morphometric analyses of living and fossil cats, including the only large, crouching mammals, to study the evolution of locomotion, the mechanical consequences of size-related morphological evolution, and the evolution of correlations (modularity) in the postcranial musculoskeletal system.”

Above: snow leopard (headless) reconstructed and taken for a spin

Our study will integrate some prior studies from Anjali’s group, on modularity for example, and from my group, on the apparent lack of postural change with increasing size in felids (most other birds and mammals get more straight-legged as size increases, to aid in support, cats don’t– paper forthcoming). How does the neglected vertebral column fit into these limb-focused ideas? We’ll find out!

And it’s all very freezer-based research, using a growing stock of specimens that we’ve collected from zoo/park mortalities, many of which are kindly being supplied by Dr. Andrew Kitchener from the National Museums Scotland. We’ll be scanning, dissecting, measuring and modelling them and then returning the skeletons to be curated as museum specimens. This page features five sets of felid specimens involved in the research. We’ll be presenting plenty more about this research on this blog and elsewhere as it continues!

Above: ocelot from Freezermas day 1, now in 3D!

The Bag-o-Cats: whole specimens of a black-footed cat (Felis nigripes), juvenile cheetah, and juvenile snow leopard. I think. Sometimes you get a bag-o-cats and are not sure.

The Bag-o-Cats: x-ray CT slice showing whole specimens of a black-footed cat (Felis nigripes), juvenile cheetah, and juvenile snow leopard. I think. Sometimes you get a bag-o-cats and are not sure.

Panthera atrox (large American lion) from the NHM in LA. Oh yes we'll be applying our insights to strange extinct cats, too!

Panthera atrox (large American lion; “Naegele’s giant jaguar”) from the NHM in LA. Oh yes we’ll be applying our insights to strange extinct cats, too!

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