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Posts Tagged ‘elephants’

This is the mammoth image I remember, from a 1971 book, with no artist credited. It's actually not as good as I remember, by modern standards at least.

This is the mammoth image I remember, from a 1971 book, with no artist credited. It’s actually not as good as I remember, by modern standards at least.

Mammoths and I go way back, not quite to the Ice Age but at least to the late 1970s with my family’s visits to the University of Wisconsin Geology Museum, and Milwaukee Public Museum, to name two prominent places that inspired me. And one of my favourite science books had a colourful mammoth painting on the cover (above), an image that has stayed with me as awesomely evocative.

Stomach-Churning Rating: 3/10. But there’s a butt below, but that’s too late for you now. And there’s poo and other scatological (attempts at) humour. Otherwise, bones and a baby mammothsicle.

Fast forward to the 2000’s and I’m studying mammoths, along with their other kin amongst the Proboscidea (elephants and relatives). I even bumped into a frozen mammoth in Sapporo, Japan, nine years ago–

Yep. That's what it looks like. Nope, not the front end. That orifice is not the mouth. This is the XXXXX mammoth.

Yep. That’s what it looks like. Nope, not the front end. That dark orifice is not the mouth. This is a mammoth that was found on Bolshoi Lyakhovsky island, in the east Siberian arctic (New Siberian Islands archipelago), in 2003. Just think of finding this and being all excited then realizing, “Jackpot! Wait… Oh man, I just found the ass. I’ve discovered a mammoth bunghole, dammit.” Still, it’s pretty damn amazing, as frozen Ice Age buttocks go. I’d love to find one. I would not be bummed.

found on Bolshoi Lyakhovskiy island in 2003

What I know now that I didn’t realize as a kid, is that a mammoth is an elephant in all but name. Mammoths are more closely related to Asian elephants than either is to African elephants, and all of these elephants are members of the group Elephantidae. If we saw a smallish Columbian mammoth, we’d probably mostly look upon it as similar to a slightly hairy Asian elephant (but a scientist would be able to spot the distinctive traits that each has). Only woolly mammoths adopted the uber-hirsute state that we tend to think of as a “mammoth” trait. Think about it: a big animal would benefit most from a thick hairy insulation in an extremely cold habitat, and Columbian mammoths ranged further south than Woolly ones. No mammoths were radically different from living elephants, unless you count the dwarf ones. But as a kid, like most people do, I saw them as something else: an exotic monster of the past, eerily unlike anything today, and bigger too. And mammoths have the added mystique of the extinct.

Now I see mammoths as neither exotic nor that far in the past. Giant ground sloths, now those are still alien and exotic to me. I don’t get them. I know elephants pretty well, and I can understand mammoths in their light and in light of mammoth fossils. Various mammoth species persisted as late as maybe 10,000 (for the Woolly and Columbian species; the latter seeming to vanish earlier) to <4000 (for isolated Siberian forms) years ago, into quasi-historic times. And only some mammoths got larger than African elephants (Loxodonta) do, such as Columbian mammoths (~10,000 kg or more maximal body mass; Loxodonta is closer to 7-10 tonnes at best).

Lately, coincidence has brought me new knowledge of – and even greater interest in – mammoths.

First, a fortunate last-minute visit to Waco, Texas’s “Mammoth Site” (see my Flickr photo tour here) two weeks ago during a short visit to give a talk in that fine central Texan city.

Second, the subject of today’s post: the Natural History Museum’s new special exhibit “Mammoths: Ice Age Giants“, which is open until 7 September. The exhibit was created by the Field Museum in Chicago, but the NHM has given it a special upgrade under the expert guidance of mammoth guru Prof. Adrian Lister of the NHM, who was very kind to give me a tour of the exhibit.

What follows is primarily a photo-blog post and review of the exhibit, but with some thoughts and facts and anecdotes woven through it. Dark setting, glass cases, caffeination, crowds, and mobile phone camera rather than nice SLR in hand means that the quality isn’t great in my images– but all the more reason to go see the exhibit yourself! All images can be clicked to em-mammoth them.

On entry, one views a mammoth skeleton with a timelapse video backdrop that shows how the landscape (somewhere in USA) has changed since ~10,000 BCE.

On entry, one views a mammoth skeleton with a timelapse video backdrop that shows how the landscape (somewhere in USA) has changed since ~10,000 BCE.

The first part of the exhibit does a nice job of introducing key species of Proboscidea (elephants and their closest extinct relatives), with a phylogeny and timescale to put them into context, starting with the earliest forms:

The first part of the exhibit does a nice job of introducing key species of Proboscidea: from early species like Moeritherium...

from species like the tapir-sized Moeritherium

Skull of Moeritherium, reconstructed. Not that different from an early sirenian (seacow) in some ways, and general shape.

Skull of Moeritherium, reconstructed. Not that different from an early sirenian (seacow) in some ways, and general shape, whereas still quite a long way from a modern elephant in form– but the hints of tusks and trunk are already there.

...To the early elephantiform Phiomia, here shown as a small animal but I'm told it actually got quite large. And continuing with giant terrestrial taxa...

…To the early elephantiform Phiomia, here shown as a smallish animal but I’m told it actually got quite large. And continuing with giant terrestrial taxa…

I was awed by this reconstruction of the giant early elephantiform relative Deinotherium, with the short, swollen trunk and downturned tusks-- so bizarre!

I was awed by this reconstruction of the huge early elephantiform-relative Deinotherium, with the short, swollen trunk and downturned tusks– so bizarre!

Looking down onto the roof of the mouth of a NHM specimen of Deinotherium.

Looking down onto the roof of the mouth of an NHM specimen of Deinotherium. Big, sharper-edged, almost rhino-like teeth; far from the single mega-molars of modern elephants.

The lower jaw (top) and fairly straight tusk (bottom) of the widespread, early elephantiform Gomphotherium.

The lower jaw (top) and fairly straight tusk (bottom) of the widespread, early elephantiform Gomphotherium.

The big "shovel-tusker" elephantiform Amebelodon. This was one of the earliest stem elephants I learned of as a kid; the odd tusks still give me a sense of wonder.

The big “shovel-tusked” elephantiform Amebelodon. This was one of the earliest stem elephants I learned of as a kid; the odd tusks still stir wonder in me.

Amebelodon lower jaw, sans shovel tusks.

Amebelodon lower jaw, sans shovel tusks. Extended chin looks like some sort of childrens’ fun-slide. To me, anyway.

Next, there are some fun interactive displays of elephant biomechanics!

How would a mammoth hold up its head? This lever demonstration shows how a nuchal ligament helps.

How would a mammoth hold up its head? This lever demonstration shows how a nuchal ligament helps. Tension on the nuchal ligament is a force that acts with a large lever (represented by the big neural spines on the vertebrae around the shoulders, forming the mammoths’ “hump” there), creating a large moment (i.e. torque; rotational force) that holds the head aloft.

I love this robotic elephant trunk demonstration. It captures some of the weirdness of having a muscular hydrostat attached to your lip.

I love this robotic elephant trunk demonstration. It captures some of the weirdness of having a muscular hydrostat attached to your lip and nostrils. Not so easy for a human to control!

But forget the myths about elephants having 40,000 to 150,000 muscles in their trunk. They have three muscle layers: a circumferential one, an oblique one and a longitudinal one. Like any muscles, especially ones this large, the layers each consist of many muscle fibres. That’s where the 40-150k myth comes from, but muscle fibres (cells) are at a more microscopic level than whole muscles (organs). Elephants do have excellent control of their trunks, but it’s not magical. It’s just different.

Then we come to the centrepiece of the exhibit, the ~42,000 year old Woolly mammoth (Mammuthus primigenius) baby “Lyuba“, which the NHM added to the original exhibit in this new version, as a star attraction — and a big win. Adrian Lister related to me how he’d never seen Lyuba in person before (access to it was tightly guarded for years). So when the NHM received the crate and held a press event to open it and reveal Lyuba, a journalist asked Adrian to act excited, to which he responded something like, “I don’t need to act! I’m very excited!” I would be, too! Full story on Lyuba’s arrival, by NHM site here. A key paper on Lyuba by Fisher et al. is here.

Studies of tooth growth in Lyuba reveal her gestation period (like living elephants, around 22 months), season of birth (early spring), and age at death (1 month), among other information.

Studies of tooth growth in Lyuba reveal her gestation period (like living elephants, ~22 months), season of birth (early spring), and age at death (~1 month), among other information.

Here we can see the right ear, which was gnawed off along with the tail by dogs of the reindeer herders that found and retrieved Lyuba. Regardless, there's loads of anatomy preserved! A hump of juvenile "brown fat" atop the head, very strange flanges on the trunk (also visible in 1 other frozen mammoth specimen, but here preserved very clearly!), and more visible postcranially...

Here we can see the right ear, which was gnawed off along with the tail by dogs of the reindeer herders that found and retrieved Lyuba in 2006. Regardless, there’s loads of anatomy preserved!

A hump of juvenile “brown fat” sits atop the head and neck of Lyuba. This probably was  metabolized during growth to warm the baby; brown fat is packed with mitochondria and thereby conducts what is called “non-shivering thermogenesis”. Furthermore, Lyuba has very strange flanges on the trunk (also visible in 1 other frozen mammoth specimen, but here preserved very clearly! What were they used for?). More details are visible postcranially…

The body was naturally “freeze-dried”, with the addition of later rounds of soaking in formalin and ethanol, leaving the body dessicated and stiff, permanently stuck in a lifelike pose as seen below:

Whole view from an exhibit panel (you cannot photograph the specimen but these are fair game!). Here we see hair on the right forearm and remnant of the ear, and the labia and nipples showing it is a female mammoth are also preserved. The head-hump is lost during growth, and the shoulder changes to change the Asian elephant-like convex curvature of the back into the characteristic humped-shoulder form of a mammoth. But ontogeny still reveals the evolutionary connection of Elephas and Mammuthus.

Whole view from an exhibit panel (you cannot photograph the specimen but these are fair game!). Here we see hair on the right forearm and remnant of the ear, and the labia and nipples showing it is a female mammoth are also preserved. The head-hump is lost during growth, and the shoulder changes to change the Asian elephant-like convex curvature of the back into the characteristic humped-shoulder form of a mammoth. But ontogeny still reveals the evolutionary connection of Elephas and Mammuthus.

Lyuba and scientists studying her, which also shows how rigid the carcass is.

Lyuba and scientists studying her, which also shows how rigid the carcass is; one can almost stand it up. Inside the digestive tract, researchers found chewed up plant material that was probably dung eaten by the baby to gain vital bacterial digestive flora, and Lyuba had plenty of body fat and ingested milk, indicating that she did not starve to death. Rather, vivianite in the respiratory tract indicates drowning as the cause of her demise. Perfusion of the body by these vivianites may have helped to preserve the body.

Answering an question the public may be wondering about: is the hype about cloning a mammoth very soon true? Nope. Well addressed, including what to me is the urgent question: would cloning a mammoth be ethical?

Answering a question the public may be wondering about: is the hype about cloning a mammoth very soon true? Nope. Well addressed, including what to me is the urgent question: would cloning a mammoth be ethical?

The fourth part of the exhibit takes on a largely North American focus to first illustrate what mammoths were like biologically, and second to wow the visitor with some huge beasts in full body, full scale glory, as we shall see!

Mammoth hair! These samples and recent molecular studies show that mammoths were not ginger-coloured as we long thought, but rather the ginger color comes as the dark grey-brown-black colour fades postmortem, as a preservational artefact. I didn't know that; cool.

Mammoth hair! These samples and recent molecular studies show that mammoths were not ginger-coloured as we long thought, but rather the ginger color comes as the dark grey-brown-black colour fades postmortem, as a preservational artefact (story here). I didn’t know that; cool.

Mammoth chow!

Mammoth chow! I liked this addition to the exhibit. This brought mammoth ecology closer to home for me.

Mammoth poop!

Mammoth poop!

After the biology explanations, let there be megafauna!

Mammoth skull! A nice one, too.

Mammoth skull! A nice one, too.

Top predators of Ice Age North America: Arctodus (short-faced bear) and Homotherium (sabre-toothed cat).

Top predators of Ice Age North America: Arctodus (short-faced bear– does the short face mean they were happy, unlike a long face? Sorry but they never are shown as very happy, unless it is the joy of whupass) and Homotherium (the other sabre-toothed cat; not the longer-toothed Smilodon).

Skulls of North American megafauna: left to right, top to bottom: horse, short-faced bear, giant sloth, then camel, sabretooth,  rabbit, direwolf (viva Ned Stark!), and pronghorn antelope.

Skulls of North American (mega)fauna: left to right, top to bottom: horse, short-faced bear, giant ground sloth, then camel, sabretooth cat, rabbit, direwolf (viva Ned Stark!), and pronghorn antelope.

Mastodon skeleton!

Mastodon (Mammut americanum) skeleton!

Mammoths seem to have been wiped out by a combination of climate change and habitat fragmentation, combined with what this item symbolizes: human hunting. This beautiful piece is the main part of an atlatl, or javelin-hurling lever. It would give Ice Age hunters the extra power they'd need to penetrate mammoth hide and cause mortal injuries.

Mammoths (and perhaps mastodons, etc.) seem to have been wiped out by a combination of climate change and habitat fragmentation, combined with what this item symbolizes: human hunting. This beautiful piece is the main part of an atlatl, or javelin-hurling lever. It would have given Ice Age hunters the extra power they’d need to penetrate mammoth hide and cause mortal injuries. It is also a great tie-in to my recent post on the British Museum’s odd-animals-in-art.

Finally, the exhibit surveys the kinds of mammoths that existed- there is a huge reconstruction of a Columbian mammoth near the mastodon (above), then smaller kinds and discussions of dwarfism, which is another strength of NHM mammoth research:

Woolly mammoth lower jaw (right) and its likely descendant, the pygmy mammoth of the Californian coastline, Mammuthus exilis.

Woolly mammoth lower jaw (right) and its likely descendant, the pygmy mammoth of the Californian coastline, Mammuthus exilis.

The world's smallest mammoth (left), molar tooth compared with that of its much larger ancestor Palaeoloxodon. The status of Mammuthus creticus as a dwarf mammoth from Crete was cemented by Victoria Herridge and colleagues, including Adrian Lister at the NHM.

The world’s smallest mammoth (left), molar tooth compared with that of its much larger ancestor Palaeoloxodon. The status of Mammuthus creticus as a dwarf mammoth from Crete was cemented by Victoria Herridge and colleagues, including Adrian Lister at the NHM.

Pygmy mammoth reconstruction. Shorter than me. I want one!

Pygmy mammoth reconstruction. Shorter than me. I want one!

In the end, from all that proboscidean diversity we were left with just 2 or 3 species (depending on your species concepts; it's probably worth calling the African forest elephant its own species, Loxodonta cyclotis). The exhibit closes with a consideration of their conservation and fate. Ironically, this elephant skull could not be mounted with its tusks on display, because that would be commercializing ivory usage-- even though the whole point of the exhibit's denouement is to explain why elephants need protection!

In the end, from all that glorious proboscidean diversity we were left with just 2 or 3 species of elephantids today (depending on your species concepts; it’s probably worth calling the African forest elephant its own species, Loxodonta cyclotis). The exhibit closes with a consideration of their conservation and fate. Ironically, this elephant skull could not be mounted with its tusks on display, because that would be commercializing ivory usage– even though the whole point of the exhibit’s denouement is to explain why elephants need protection!

Reactions to the exhibit: the photos tell the tale. It’s undeniably great, in terms of showing off the coolness of mammoths, other proboscideans and Ice Age beasties, to the general public. I felt like the factual content and learning potential was good. It didn’t feel at all like pandering to the lowest common denominator like some other exhibits I’ve seen (cough, Dino Jaws, cough). I loved the reconstructions, which were top quality in my opinion. I could have done with some more real skeletons, yet more realistically the exhibit hall was already large and full of cool stuff. But give me a break: Lyuba. This trumps everything. Going to see a real friggin’ frozen mammoth baby buries the needle of the awesomeness meter on the far right. That’s pretty much all I need to say. The spectacle was a spectacle.

This exhibit shows a lot of work, a lot of thought, and a personalized NHM touch that reflects the actual research (even very recent work!) that NHM staff like Prof. Lister are doing with collaborators around the globe. What more could we want, a herd of cloned mammoth babies frolicking around and tickling guests with their flanged trunks? Don’t hold your breath.

You’ve got just over 2 months to see the exhibit. Don’t come complaining on September 8 “BBBBBbbbut I didn’t know, I didn’t think it would be that cool! I just thought there’d be a guy in a Snuffleupagus suit signing autographs!” You have a duty as a Freezerino to go bask in the frozen glory of these Ice Age critters. There may be an exam at the end. :)

Is the exhibit kid-friendly? More or less. The text is more targeted at teenager-level or so, but the visual impact is powerful without it. I’d warn a sensitive child about the withered baby mammoth body before showing it to them, so they aren’t caught off guard and scarred by the experience. I saw plenty of kids in the exhibit and they all seemed happy. Parents may want to linger longer and absorb all the interesting information, whereas kids may blitz through or goof around, so plan accordingly if you’re inbound with sprogs.

You know what I was eyeing up in the gift shop...

You know what I was eyeing up in the gift shop…

Aside: The frozen mammoths get me wondering- what else does the Siberian (or extreme northern Canadian/Scandinavian) permafrost conceal? There are a lot of awesome Ice Age megafauna I’d cut my left XXXXX off to study quasi-intact… think about how amazing it would be to find a giant ground sloth (not bloody likely), sabretooth cat, or other species. There’s a lot of north up north. A lot of space and ice. A lot could happen. And climate change will make discoveries like this more likely, while the melting (and humanity) lasts…

Wool we ever find the Lyuba of woolly rhinos? It could happen.

Wool we ever find the Lyuba of woolly rhinos (Coelodonta)? Cast of a mummified woolly rhino from the NHM’s entry hall. More of these finds are likely, I’d say.

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A very short post here to plug BBC Radio 4’s excellent second series of “Just So Science”. These are 15 minute stories involving a reading of parts of Rudyard Kipling’s great British/natural history stories, and then examining how the science of today informs us about the real lives of animals, without resorting to just-so stories a la Kipling (co-opted as a term in evolutionary biology, too!). I was featured last year on rhinos.

I’m featured this year on kangaroos (now available online) and elephants (also available online now). I just listened to the kangaroo episode and it was good fun. I’ve studied the biomechanics of kangaroos a bit, in as-yet unpublished work featured here in a BBC News story (video from that work is below), and we’ve done other work on their bone morphology and how it relates to body size that is sure to come out in not too long.

Don’t blink! Or, for your enjoyment, a looping GIF:

kangaroo hop

My freezers feature heavily in one bit, in which you can hear me vent my frustrations about an unlabelled bag and stacks of specimens– where is the wallaby? And what’s that crinkling noise?

Best beloved, it is the sound of science. Just so. Enjoy!

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Welcome back to my two-part British Museum series; I covered crocodiles before. Here, I celebrate the less common creatures depicted in human art, design and culture. And we begin back in Egypt, with a bit of crocodile to provide a nice segue:

With the head and torso of a hippo, the legs of a lion and the tail of a crocodile, the Egyptian goddess Taweret just rocks. More info here- https://www.britishmuseum.org/explore/highlights/highlight_objects/aes/b/breccia_statue_of_taweret.aspx

With the head and torso of a hippo, the legs of a lion and the tail of a crocodile (not easily visible here), the Egyptian goddess Taweret just rocks. More info here.

Anatomy in art is best when the anatomy is actually used as a substrate for art, as in this later piece from Egypt, and another piece that follows it:

Scapula (shoulder blade) from an ox, from Roman Egypt. Click to embovine for closer examination and explantion.

Scapula (shoulder blade) from an ox, with Roman enscriptions. Click to embovine for closer examination and explanation.

~8000 BC red deer antler headdress from England (click to enstaggen for closer examination and text details).

~8000 BC red deer antler headdress from England (click to enstaggen for closer examination and text details in upper left). Picturing an Ice Age shaman wearing this gives me a sense of awe.

Human anatomy in our artwork, to my mind, reaches its pinnacle in Aztec religious masks like this, which was too cool to omit:

Use of a human skull to make a stunning mask decorated with obsidian, representing Tezcatlipoca, the Smoking Mirror and master of creation/destruction; slayer of Quetzalcoatl. Badass dial turned to 11!

Use of a human skull to make a stunning mask decorated with obsidian, representing Tezcatlipoca, the Smoking Mirror and master of creation/destruction; slayer of Quetzalcoatl. Badass dial turned to 11! He is also sometimes represented as a jaguar.

Continuing the mask theme, the following masks show off sawfish, sharks and other species from the region:

Awesome diversity of ceremonial fish masks from Africa.

Awesome diversity of ceremonial fish masks from Africa.

Lions find their way into plenty of artwork such as European royal heraldry. Yet the huge depictions of an Assyrian lion hunt in the British Museum are not only anatomically impressive but also evocative of a time long past, when Asian lions ranged far across human territories. In viewers today, however, they may inspire more sympathy for the fleeing lions than awe for the lordly charioteers, horsemen and archers that pursue them.

Assyrian lion hunt Royal Lion Hunt

I finish with some statues and other depictions of animals that are more globally uncommon than lions:

You don't see tapirs much in art but here seems to be one, as a bronze statuette from ~400s AD in China.

You don’t see tapirs much in art but here seems to be one, as a bronze statuette from ~400s AD in China.

Statue of the Indian elephant diety Ganesha from ~750 AD. As the placard explains, Ganesha got his elephant's head when Shiva freaked out and cut off the human one, then promised to make amends by substituting the head of the next animal he saw.

I love Indian artwork for its plethora of proboscideans. Here, a statue of the Indian elephant diety Ganesha from ~750 AD, engaged in a dance. As the placard explains, Ganesha got his elephant’s head when Shiva freaked out and cut off the human one, then promised to make amends by substituting the head of the next animal he saw.

North Chinese (~11-12th century) ceramic plate depicting a funky, vaguely humanoid dancing bear tied to a pole.

More dancing! North Chinese (~11-12th century) ceramic plate depicting a funky, vaguely humanoid dancing bear tied to a pole. The anatomical exaggerations here make the piece more memorable and vaguely demonic, but not so much as the next item.

The dance is over, thanks to ass demons. That’s right, ass demons. Many Burmese were surely frightened or inspired by these terracota warriors from 1400s AD. These warriors represented king Mara’s forces that attempted to disrupt the Buddha’s meditation. As ass demons would tend to do. (I hate it when that happens)

I hope you enjoyed this brisk dance through atypical animals and their anatomy in artwork! Coming next, a look at one of the greatest anatomists ever.

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…a daily picture of anatomy! And today it is four pictures; da-da-dee! ♫

Welcome back again, again to Freezermas! 

Today I’m shimmying down your interwebz with a late delivery. I’ve promised before to show how we clean up our nasty gooey skeletons to preserve them for future research to use. This is the intended final destination of all critters that are tenants of my freezers– the freezer is just a lovely holiday home, but bony heaven is the end result. I’ve accumulated a little museum of the bones of exotic animals I’ve studied, using these cleaned specimens. Here is how I do that preservation– there are four basic steps, and I’ll show them in four photos.

Stomach-Churning Rating: 8/10; first just dry bones, but then some gooey bones and by the end we ratchet it up to bloody organs.

Step 1) We get the deceased animal from various zoos and other EU sources, CT/MRI scan it, and dissect it. That’s what most of this blog focuses on, so I won’t show that. But I will show the end result, and then how I get to that:

ele-rhino-bones

Those are some elephant and rhino bones, some of which you saw on the 2nd day of Freezermas. Elephant bones are super greasy; it’s almost impossible to get rid of that brown grease visible in this photo (upper LH side) without making the bones brittle and over-bleached. The bones of the whiter white rhino on the right show what I’m usually aiming for. How do I get this done? Well, here’s an example for an elephant shank:

Cookin' up elephant shank

I take the elephant shank and make soup.  (above) An Asian elephant’s patella, tibia and fibula were dissected, frozen for many years (queued up for cleaning; much freezer burn occurred on this specimen— it was jerky-fied), and then thawed. I put large specimens in this Rose cooker unit, which is a big ham cooker with a heater unit at the bottom. My baby, a Rapidaire MKV 5-ham unit is shown; oooh, ahhh!

The Rose cooker is filled up with tap water and been set it at around 60-90C. Then I let it cook away! A brothy soup develops, and sometimes it smells rather nice (my favourite aroma is giraffe leg). Sometimes… it’s not so nice. We check it every few hours to top up the water and remove stray tissue, and then change the water every day or so.

An elephant shank like this will take 2-3 days of cooking, longer if only switched on during work hours. The key thing is not to let it cook dry, which happened once with a faulty Rose cooker that did not do its normal auto-shutoff when the water ran low… showing up to work to encounter some fire trucks and unhappy college Health & Safety rep is not a good way to start your day, trust me!

This step is only slightly different for smaller (<30cm) specimens. Rather than the Rose cooker, we use the lovingly named “Croc Crock”, which isn’t visually impressive but you can see it here. As the name indicates, we’ve mainly used it for small crocodiles, and it is a crock pot. (a helpful thing is to add some detergent to the water for these small specimens; then bleaching isn’t so necessary)

Step 2) Then I empty out the water through the bottom spout, do the very nasty job of cleaning out the fat and other tissue that has accumulated (think 20 gallons of goo), hose off the bone, and set it in a ~10% bleach solution for at least a day, or up to a week or so for an elephant bone. Once it’s cleared up, I leave it out to dry (for big elephant bones, copious amounts of grease may be emerging for a few weeks). And then…

Elephant shank bones

Step 3) I varnish the dry bones with a clear varnish, and let them dry. Here is how that elephant shank turned out. Pretty good! Finally, they get to join their friends:

The bone shelves

Step 4) The prepared bones are labelled, given a number/name that I file in a world class comprehensive electronic database (cough, get on that John, cough!), and they become part of my humble mini-museum, shown above. Voila! The chef’s job is finished. Let science be served!

Happy Freezermas! Sing it: “On the fourth day of Freezermas, this blo-og gave to me: one tibiotarsus, two Darwin pictures, three muscle layers, a-a-and four steps of bone cookery!” ♪

Oh it’s Valentine’s day, so, err, have a heart today. Have four, actually!

giraffe heart - 1 white-rhino-heart-Perez Windfall-ele 054

chicken-heart

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Welcome to the first of a series of image galleries with highlights from the RVC‘s Anatomy Museum! Our veterinary school dates back to the 1789 epic dissection of the unbeaten racehorse Eclipse by surgeon Mr Charles Vial de Saint Bels, which led to the college’s founding in 1791 (incidentally, the RVC retains Eclipse’s skeleton to this day, and 80% of living racehorses come from Eclipse’s lineage!).

What, you didn’t know we have an anatomy museum? Well this is another of London’s many hidden museum treasures. It is based at our Camden campus, just a 10min jaunt from King’s Cross or St Pancras stations (or Mornington Crescent tube), in the colourful Camden Town neighborhood. It doesn’t have its own website, yet, and my posts are not intended to play that role, but I want to informally and unofficially celebrate its glory because I think we have a great museum full of wonderful features and people deserve to see them.

For example, when I first interviewed for (what became) my job at the RVC in 2003, one of the first sights at the Camden campus was the original, classic ~Victorian style (dark and gloomy, stained wooden cabinets, room chock full of skeletons) anatomy museum which presented the entrant with a lovely view of this:

Which sadly is my only photo of the skeleton of an Asian elephant that shows it in its original position, crowded next to the skeletons of a white rhino, common hippo, horse and other animals. If you know me and my penchant for giant critters, that was like being shown the Promised Land! Since then, modernity has required us to clear out the dusty Victorian room and rehouse the specimens in more airy, spacious surroundings. Which has worked out pretty well in our case, I think. Here is the elephant now, in the midst of our cafe next to our Anatomy Museum (sadly, the rhino and hippo are mostly now tucked away in storage, and no, there is no rhino horn here for people to steal. Sheesh!):

Much easier to walk around, drink coffee with, etc., and it has gained a second skull (with the skull of a baby also on display nearby). So you might immediately be able to see why I like our museum– any museum with a mounted elephant skeleton rocks, in my opinion. But also, I’m gradually cleaning up my freezer specimens, building a little museum of “my” own that will eventually become an official part of the RVC museum’s collection, so there is a connection to this blog too.

Anyway, here is what a visitor gets as a first impression upon entering our museum:

Namely, a horse who is less famous than Eclipse but still no slouch in his day, Foxhunter the show jumping horse, who won Britain its only gold medal at the Olympics 70 years ago (nice timing)! Then, looking around the museum, you will see:

A cow skeleton to your left, which is no shock at a vet school, but then look more closely, to the right:

A nice tiger skeleton is mounted there, with a pig skeleton atop it, and a hippo skull hanging out nearby (closer view of that in a later post). Through the green doors to the right is our lovely cafe, with the elephant and a few more specimens including a splendid mount of a sitting polar bear (to be shown later). And then, meandering around back to the left through the museum hall you will find:

A nice replica chimp skeleton next to a cast of “Lucy”, the famed Australopithecus early hominin! So there’s some decent evolutionary context in the exhibit, too; not just your standard domestic critters with little broader conceptual unification. But I think some of the museum’s greatest treasures  are the preserved specimens of lovingly dissected animal anatomy demonstrations, such as toward the back of the room:

These were done over past decades, many winning awards for the skill displayed in making them, and it is sad that this skill is becoming more and more rare, with shifts toward less hands-on, more computerized education and training. At least BodyWorlds and Animal Inside Out bucks this trend! It’s fortunate we have museums to show off the skill of preparators and dissectors so the beauty of such specimens can continue to be appreciated. I’ll show some closeups later.

There are plenty of surprises in the RVC’s Anatomy Museum, so if you get a chance and expect to be near our Camden Campus, come take a look sometime. Casual, unheralded visitors are not normally welcome, as the museum is more of an in-house educational resource than a public one. But I am told that scientists could easily get entry to study specimens on prior request, and with plenty of advance notice other members of the general public probably could, too. Mr Andrew Crook (recently awarded an MBE for his efforts using our museum and other facilities to educate local students) is the main contact person but please don’t swamp him with requests. It would be best to contact me first for advice and contact details.

So there’s a little introduction to our Anatomy Museum, and coming posts will show you more of the cool specimens within– stay tuned!

I’ll have our friend the ostrich skull show you the way out–

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Title is so meta?

OK Londoners, and Olympics visitors, and anatomy (or just science/biology) buffs, and those not lucky enough to see other versions of the animal Body Worlds show. You have a mission. And that mission is to go see “Animal Inside Out”, a special (£9 for adults is well worth it!) exhbit at the Natural History Museum, open until September 16. This blog will self destruct, very messily, by turning itself inside out in 5 seconds… Boom.

Hippopotamus attempting to outdo elephant guts.

Anatomy to me is beautiful even when it’s “ugly” (messy, wet, mucosal, intestinal, asymmetrical, unlike human, whatever), and that’s a major theme of this blog. Hence I am embarrassed that I hadn’t yet gone to see this Body Worlds spinoff exhibit until now, but can begin to shake off that shame by means of an almost exclusively effusive gushing of blood love for said exhibit. Wow, wow, wow! I went in with no particular expectations, having seen some pictures and knowing some of what to expect, and having other things on my mind. I came out very pleased; the NHM exhibits folks and von Hagens’s crew have created an inspirational spectacle that could do wonders for anatomical sciences and natural history. More about that at the end.

(Warning: possibility of spoilers, but the exhibit is so visual that I don’t think my descriptions can spoil it)

The entrance

No photos are allowed as usual, so all I have to show you is the entrance and some anatomy pics I’ve interspersed from my team’s research to lighten up the text. I suppose I could have asked for special permission to take photos for review usage but this was a very impromptu visit, and with ~4 months of showing left I may well be back again.

Weighing a hippo; spot on at 1600 kg!

There is a brief panel on homology and why it is the major concept underlying comparative anatomy (and a key part of evolution, co-opted from the not-so-evolutionary ideas of Sir Richard Owen, whom the NHM rightly mentions here). Another panel rightly brings up the issue of ethics, which has plagued Body Worlds before. It comforts the visitors that animals were not slaughtered just for this display and that the NHM applied its strict collections criteria to them. Convincing enough for me, and absolutely necessary to bring up early on.

The entry hall then presents you with about five cephalopods (labelled “squid” and “octopus”—a gripe is that species names/details are not given for most specimens on show) prominently occupying the view. The cephalopods, like basically everything else, are plastinated (by a now US-patented set of procedures, I learned from the exhibit book detailed later). They are stunningly frozen in lifelike poses or with gaping cuts to show their interior anatomy, although there was very little explanation here about cephalopod biology and anatomy (about 1 smallish panel). No mention of Cthulhu. Damn. He’d approve of the Grand Guignol scenery.

Toward the back of the first corridor of specimens and cases, there is a stunning scarlet haze outlining the body of a “shark” (species not given) with its huge liver lying below it. The haze, a technique used repeatedly throughout the exhibit, is some kind of corrosion cast of the circulatory system, I gather. A bunch of cross/longitudinal sections of cephalopods, crocodiles, fish, horse hooves and other animals decorate blank spaces on the walls, some with labels showing basic features and some just hung like paintings. Fair enough, but a missed opportunity for a bit more educational content here.

Gratuitious Melanosuchus (black caiman) shot.

A smallish whole shark confronts you as you turn the corner from the crimson chondrichthyan; again of unknown classification. One would think a museum exhibit would care about classification beyond “shark,” but oh well, I am banging the same drum here too much and missing the point, that the exhibit is really a visual, visceral expose rather than a deep prose-driven intellectual dissection. On one of the shark panels it is noted that sharks have red and white kinds of muscle used for slower and faster swimming, but not clarified that this is a very widespread vertebrate (chordate?) feature. This forms my second gripe, that a truly evolutionary approach, such as that taken by dozens of the museum’s research staff as their major paradigm of phylogenetic systematics, could have helped the public grasp the evolutionary, hierarchical nature of homology and depart with accurate information about what features characterize groups at which levels. I’m not asking for cladograms laid out on the floor as at the American Museum of Natural History, although maybe that could work, but the exhibit tended to fall back on an outmoded “this animal has this feature, and that animal has that feature, and these are cool adaptations” shopping list approach rather than a modern comparative approach. Granted, almost all museum exhibits fall into this trap, for various reasons and some of them justified. But with a spare word or phrase here or there, this could have been done better without drowning the visitors in that dreaded sea of bloodprose.

Passing the sharks, we come to one of several thematic sections about body systems, this first one on the skeleton (later, brain/nerves, circulation, muscles, etc.). A few small skeletal specimens of the type that are seen throughout the museum are presented, with a scallop reminding us that skeletons can come in many types among multicellular organisms. There is a horse skull and a stark white whole skeleton of a young-ish ostrich, which was very nicely mounted. However, I was caught off guard by the pelvis, which lacked the curved, ventral “boot” like connection of the pubic bones that ostriches have—presumably explained by its juvenile status although I wasn’t 100% sure it was even an ostrich pelvis. OK, I am having a serious pelvis-nerd moment here; forgive me as my PhD was on this stuff.

Ostrich in the midst of disassembling.

BUT, once again the small interpretive panel had a moment of Fail. The ostrich was explained to have two toes, in contrast to normal birds which have “five”.  HUH? Birds have three main toes and variably also a fourth, inner (first) toe called the hallux, used for perching and other activities including walking. None have a fifth toe; indeed their dinosaurian forebears lost that feature some 230ish million years ago. Just an embryonic vestige of the base of the fifth toe is visible in bird embryos today. Furthermore, the panel said that two toes in ostriches can grip the ground more strongly than more toes in other birds. I know of no evidence that shows this, and suspect that the contrary might be true. The standard explanation for toe reduction in ostriches is that it is a lightening feature characteristic of “cursorial” (long-legged, sometimes fleet/efficient) animals, to make swinging the long legs easier. These errors really should have been caught by involving experts in polishing the scientific content of the exhibit.

But I don’t want this post to grumble too much; wrong message. There was so much to celebrate in this exhibit, which was felt impressively spacious and full of cool specimens! Visitors pass some plastinated whole sheep and goats, with panels nicely explaining that goats and sheep look quite similar on the inside and are evolutionary relatives. Having “four stomachs” (technically, a four-chambered stomach; not four distinct organs that were duplicated) is attributed as a sheep trait, then being a ruminant is said to be a goat trait; this might get a little confusing for non—anatomists (both are ruminants and have similar stomachs).

I learned that goats have an extra tail muscle that allows them to swing up/down as well as side-to-side. Hey, I teach veterinary anatomy and I don’t know that!? I must tuck my tail between my legs in shame, but I am no goat so I do not think I can (do satyrs count?). But I wasn’t so sure that goats, as described, were the first animals to be domesticated—I thought that was dogs? Ahh, Wikipedia says dogs, then sheep, then pigs, then goats? I’m outside my expertise here, I admit, and resorting to Wikipedia out of ignorant desperation. Anyway, here, another instance of coulda-been-more-phylogenetically-specific presented itself: the forelimb of goats was said to be connected to the thorax by muscles and ligaments, not a joint, but this is a feature common to most Mammalia. Although audience attentions might be wandering at this point, waiting for the next big spectacle (goats and sheep are not a big crowd draw, even plastinated), some more care as to what was written would be good. Some reindeer and horses and other animals join in the fun later on. Good, but mostly ‘filler’ (wise to put these in the middle of the exhibit, after sharks/cephalopods and before climax) unless you’re a big fan of fairly familiar ungulates with fairly homogeneous postcrania. OK, my bias is showing…

Gratuitious image of emu curled up for CT scan.

Next along the path, a longitudinal section of a whole ostrich caught my attention. Wow again! I had no idea that one could make a section like this of such a large animal, all in one plastic sheet like a giant microscope slide! I stared at this for a while, wondering how both legs could be fit in a ~1cm thick panel, and gave up trying to understand the technology. Von Hagens, you got me there; I’m stumped. Were multiple sections glued together somehow to produce a pseudo-2D slice from many thin 3D sections? I could not tell, and felt humbled and deeply impressed by the technical skill shown in the exhibits so far…

And then the punches kept coming, one-two-three! The exhibit approaches its climax with a crescendo of great specimens in the final hall. First, another maroon marvel. A whole ostrich, standing with wings askew, showing off its entire circulatory system (plus a few wing plumes for aesthetics) from head to toes! Gorgeous, technically brilliant, and well worth at least a 5 minute walk around (you can stroll around many of the displays in 360 degrees- very good move!). A plastinated whole ostrich stands next to it, and for a muscular anatomy geek like me, it was nirvana. However, in a churlish moment I had to look away from a panel explaining that an ostrich is “too heavy to fly” (I admit some younger visitors may need reminding of this). But then I looked into the big open space of this main hall, and the climax was before me. I think I’d had my climax a few times since this, but wow this was enormous in so many ways. All the ways. Mind-blowingly, vastly, geektastically kewl.

Gratuitious rhinoceros leg.

Across from the two posed ostriches and flanked by numerous smaller specimens, the elephant and giraffe stand frozen in vigil. There is also a lovingly detailed dissection of a huge male gorilla by the back wall and exit, with a panel reminding us that gorillas are (among) “our closest relatives.” The giraffe is precariously poised on one front toe-tip, in mid-gallop. What a great pose! There is the requisite explanation of how they solve the blood pressure problem in their neck (e.g. arterial valves), but also the statement, news to me, that they are the only animals able to ruminate while running. Who figured that out and how? I really want to know! Must be hard to check. (or was walking intended? Are my notes wrong?) Across from the full-fleshed plastinated giraffe (which I could see with my eyes closed after all our dissections from a month ago), there was another visually arresting and technically monumental giraffe on exhibit: one represented completely by small, reddish cross-sectional slices, from head to toes in a standing pose. That took me a while to absorb, it was so lovely, almost like a hanging mobile of morphological splendour.

There is a panel about genes and variation and inheritance. It is brief. (and it belongs there) Thank you. Let’s celebrate anatomy for anatomy’s sake for once!

“But John,” you might say, “What about the elephant? No love for the elephant? The star of the show?”

Zoinks! I want one! Stoic and triumphant (except against death and plastination), the Asian elephant is the centrepiece of the collection. (The book explains it was “Samba” from Neunkirchen Zoo, Germany, dead of some circulatory problem in 2005 and the first one plastinated, plus the inspiration for the animal show). I was speechless and paralyzed for a moment. I didn’t even know how to start looking at the partly-exploded-to-show-its-insides elephant. I actually avoided it for a while, looking closely at the other specimens, and building up anticipation, before stepping up and taking a long, intense look at this tall drink of water.

Go see the elephant. If you know basic anatomy, look at its leg muscles. Check out the huge triceps, still attached to the elbow; I like to say it is the size of a graduate student. Same for the analogous superficial gluteal and somewhat-fused biceps femoris muscles on the rear end, around the thigh/knee joint. Huge! I’ve never been able to view a standing dissected elephant, so this really impressed me more than a table full of giant muscle slabs like I normally deal with. And best of all, for me, the “false sixth toes”; the prepollex and prehallux; are visible in all four feet (but not noted anywhere, even in the book; too bad, these things were widely known by anatomists before my work on them). So much to marvel at here. It is an anatomical treasure. I wish I had a 3D image of it to use for anatomical studies- it was so easy to identify every single muscle group (except for a few missing around the shoulder/neck), even in the distal limbs. Hmm, photogrammetry might be possible (nugget of idea begins to crawl around John’s brain like a Zimmerian parasite)…

Behold, the triceps muscle of an elephant!

Behind that gorgeous elephant, don’t miss the wall mountings of two cross-sectional slices: through the head/neck of a moderate-sized elephant (How!?!?) and distal leg (no predigits but good features). And definitely don’t miss the stool (non-fecal, furniture form). I almost did. A wooden stool is shaped like a newborn elephant and a cross-section of the body is adhered on top of it. I assume you cannot sit there, and I am very glad that it was not, as I first imagined, an actual plastinated baby elephant turned into a stool. That would be bad taste.

The exhibit is in very good taste, without exception, and although I am gore-desensitized to say the least, it is not gory in my view. The plastination process preserves the reality and even some of the colour faithfully, but renders it just unreal enough (past uncanny valley territory?) that it should not be very disturbing to most viewers.

You can’t leave with your own photographs, but you can be schnookered into buying the exhibit book (£12.99) and a couple of packages of nice colour postcards (£4 for six; excellent quality images and cardstock IMO). The book and postcards show many of the exhibit specimens but not all, and include some others that are not on exhibit. I was saddened that the bear was left out—very cool image of that in the book. I’ve only skimmed the book a bit. I was annoyed by a few mistruths about elephants (25mph running speed, “have no ankle joints, which is one of the reasons why elephants cannot jump”, the bones “do not contain any marrow”—wrong, 15mph and there are ankles, they just are not very flexible (but not immobile either); also the bones do contain marrow (how could a large vertebrate survive entirely without it???) but just not as much of it per unit volume, due to lots of spongy bone). But I am still very happy with the 139 pages chock fulla pretty images, which is all I really wanted. Indeed, the book is a great pictorial anatomical reference- some of the species such as elephants and giraffe lack a really good anatomical resource in the modern, or any, literature! The exhibit shop also sells some good anatomy texts, mostly on humans but I recommend “Animal Anatomy for Artists” very strongly; I use that regularly in my own work.

So, £29.99 of schnookering later (haha, poor victimized me!), I emerged and reflected more on what I’d seen. I’m still a bit giddy about it all. I like the minimalism in most aspects- black backgrounds, minimal signage (but just enough to make it educational—when they got the facts right), focus kept on the specimens. Well done there. The spectacle of the specimens I’ve raved plenty about- it is not at all disappointing. It is AWESOME in every sense. I feel I easily got £9 of value from the ticket, and would (probably will!) pay it again. It is a profound experience to see the rich anatomical detail exposed, and be able to circumnavigate the specimens to absorb multiple perspectives. If you know some anatomy, you’ll be doubly rewarded at least, and if you bring your own phylogenetic perspective that can be trebled.

Baby white rhinoceros. Sad infant mortality.

What makes me happiest after my visit is realizing that we are in an anatomical renaissance for science and public interest therein. Exhibits like this and documentaries like “Inside Nature’s Giants” have tapped a public interest and curiosity in the wonders of basic anatomy. Anatomy is at the core of so many biological sciences and is so immediately accessible to people, because we all have anatomy. Anatomy is at the crossroads of art and science; it is visual, variable and complex, yet concrete, objective and easy to relate to. “Animal Inside Out” is a spectacular blend of art and science. They nail the artistic aspect, and the science is done reasonably well (despite my few gripes)—the exhibit’s science speaks for itself, in a way, although many visitors will need a nudge to grasp that.

I’d like to make a call for a permanent exhibit of the likes of “Animal Inside Out” in the UK. We deserve this! Museum exhibits could use something new, other than lame, quickly broken digital pushbuttons and bland skeletons devoid of soft tissue context (although the latter can be sufficient, e.g. at the Paris NMNH). That’s what makes “Animal Inside Out” (and Body Worlds) such a hit- as Hagens is quoted on the book dustcover, animal anatomy that goes beyond digitized abstractions and dusty bones is able “to sharpen our sense of the extraordinary by looking at the self-evident.” I could not say it better myself. This exhibit is extraordinary; that is self-evident after even a peek. It is a loving tribute to how fantastic the totality of animal structure is. Go! Enjoy. Absorb. Gape. Stare. Thrill. Revel. Think. Question. IT’S BEAUTIFUL.

Impressive hippo mouth says “Farewell for now.”

Edit: @samjamespearson on Twitter has kindly posted some photos (for free NHM/AIO publicity) of the exhibits and here are the links, now that they’re out there– SPOILERS! And thanks, Sam! I don’t think these really spoil the intense visual experience of actually being there and walking around the specimens, not at all.

octopus, whelk, squid, needlefish, scarlet haze of shark, hare brain, cat nerves,  bactrian camel, another camel,  bull (I forgot to mention it; this one was pretty great!)

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This post will walk through the basic steps we take to do some of the major, ongoing research in my team. It comes from our lengthy project aiming to determine how elephant legs work at the level of individual muscle/tendon/bone organs. We need fancy computer simulations because anatomy, mechanics, physiology, neural control etc. are all very complex and not only impossible to completely measure in a living, moving animal but also extremely unethical and unjustified in the case of a rare, fragile animal like an Asian elephant. We want to do such complex things to test hypotheses about how animals work. For example, we want to estimate how fast an elephant could run if it wanted to, or why they cannot (or will not) jump or gallop like smaller mammals do— even as baby elephants (~100 kg or 220 lbs), which is an ancillary question we’re tackling. That’s cool basic science, and that’s enough for me. But the applications once such models and simulations are established are manifold– human clinical research now routinely employs such approaches to help treat “crouch gait” in patients with cerebral palsy, plan corrective surgeries, aid in rehabilitation strategies, and even potentially optimize athletic performance. Non-human research is pretty far behind this kind of confident application, because there are too damn many interesting non-humans out there to study and not many people using these approaches to study them (but it’s catching on).

Breaking up the monotony of the text with a baby elephant we met during our research in Thailand (Chiang Mai, here) in 2001. It was just a few days old and VERY cuddly and playful (chewing on everything!) but it’s mother did not want us playing with it so we only gave a quick hello.

I use the term model to refer to a simple abstraction of reality (such as an anatomically realistic computer graphic of a limb), and a simulation as a more complex process that is more open-ended and generally uses a model to ask a question (such as what level of extreme athletic behaviour a modelled limb could support). We use models and simulations to test how all the structures of the limb work together to produce movement. This also reciprocally gives us insight into the question, as I like to say it, of why is there anatomy? What is anatomy for? Why does it vary so much within so many groups and not so much in others? This can more easily be addressed by focusing on the consequences of a given anatomy rather than the more tricky question of why it evolved.

These approaches also can answer the frightening question of “Does anatomy really matter?” Sometimes it does not. And those “sometimes” can be impossible to predict- although sometimes they can be easy to predict, too. I think we are not at a point in the maturity of biomechanics/functional morphology to usually know a priori when either is the case.  Many factors in addition to anatomy determine function, behaviour, or performance; that’s why; and biomechanics aims to unravel those relationships. A lot of anatomists, palaeontologists, etc. assume that form can be reliably used to predict function, but plenty of studies have shown already (and if you peer deeply into the details, it comes from first principles) that one cannot be sure without either measuring what anatomy is doing in a particular behaviour or estimating that function in a computer model or simulation.

Anyway, I’ve covered my perspective on this in a paper which you can read if you want to go into deep philosophical details of the science (and read me blabbering on more about this particular hobby horse of mine?). This post will proceed mostly with pretty images and simple explanations, although I welcome comments and queries at the end. As part of this post, I’ll try to give an idea of the timespans involved in doing the research. Some steps are quick and easy; others can take dauntingly long — especially to do well, without building a digital house of cards.

I’ll start, as my posts often do, with a deceased animal, and in this case it will again be an Asian elephant. Incidentally it is the same animal from the “Inside Nature’s Giants” series (see previous post).

Above: the hindlimb viewed from the rear, showing the medial (inside) region of the thigh skinned down to the superficial musculature. The hip is toward the left of the screen, and the knee is to the far right (whitish rounded area), with the shank (still bearing most of its grey hide) heading to the bottom right corner of the picture. Muscles pictured include ST (semitendinosus) and SM (semimembranosus); major hamstring muscles; as well as the thin, sheet-like gracilis, the straplike sartorius, and the massive adductors toward the top of the image.

When collecting data from dissections for functional analysis including computer models and simulations, we dissect the muscles one by one as we identify and photograph/sketch them, then remove them and do a suite of measurements to characterize how their form relates to some basic functional parameters. From the mass (weight) of the muscle and the length and angulation (pennation) of its fibres (bundled as fascicles) we can estimate what is called the physiological cross-sectional area (PCSA) of each muscle, which is known to strongly correlate with the force the muscle can produce. Different muscles have different PCSAs; for example check out these pictures of a long-fibred, lower-PCSA muscle and a short-fibred, highly pennate and high PCSA muscle:

Above: the long muscle fibres (bands running from left to right, somewhat diagonally from the bottom left corner toward the top right) of a hip adductor muscle in our specimen. The adductors are fairly simple muscles that run from the underside of the pelvis to the inside of the thigh (femur).

Above: the tensor fasciae latae (TFL; pretty sure of ID but going from memory) hip muscle of our specimen, cut open to show the short, angled fibres (each leading at around a 45 degree angle to attach onto a thick central internal tendon). The TFL is just out of view at the top of the screen in the whole leg anatomy picture above; it is on the front outer, upper margin of the hip/thigh and runs down to the outer side of the knee, invested with thick sheets of connective tissue (fascia).

The maximal isometric force (Fmax) of a muscle is computed as the PCSA times the muscle stress (force/unit area), which is fairly conservative in vertebrates. A square meter of PCSA can produce around 200-300 kilonewtons of force, or about 60,000 cheeseburger-weights (the standard unit of force on this blog). That’s a lot of quarter pounders! And an elephant has pretty close to that many cheeseburgers worth of leg muscle (around 150 kg mass, very close to a square meter of PCSA; total Fmax would be around 80,000 cheese-burger weights!). That much muscle is important because an Asian elephant like this one weighed 3550 kg or about 9000 cheeseburger-weights. So if all the muscles in one elephant hindlimb could push in one direction at once, in theory they could hold about 9 elephants aloft. However, as the picture above shows, they do not all act in the same direction. Furthermore, there are many other factors involved in determining how hard a leg can push, such as the leverage of the muscle forces versus the actions of gravity and inertia (mechanical advantage). All those factors, again, are why we need computer models to address the complexity. But the end result is that elephants cannot support 9 times their body weight on one hind leg.

Enough talk about cheeseburgers and enough possibly savory pictures of giant steak-like leg muscles. I don’t want to be blamed for hunger-induced health problems in my beloved blog-readership, dear Freezerinos! The above steps take about a week to complete for 2 legs of a big elephant, rushing against decomposition to try to get the best quality data we can. On to the digital stuff- let’s turn the geekitude dial up to 11 with some videos of computer modelling.

Our next step, often featured on this blog because I do this so often, is to take CT (and/or MRI) scans of the specimen that we wisely did before we cut it to bits, and use those to make a computer model. That’s the easy step; a scan nowaways takes me less than an hour to complete, including moving the specimen back and forth between the freezer and imaging centre. MRI scans can take quite a bit longer. Here is a CT scan of a similar hindlimb (right leg for the toes up to the knee, from a juvenile elephant; the above leg was too big for our scanner!). See what you can identify here:

And then here is a resulting computer model of the same animal (just knee down to toes), showing how we took each CT slice of even the muscles and turned them into fully or partially 3D digital organs, in our case using commercial software that makes this procedure (a step called segmentation) very easy:

The segmentation step for bones is usually incredibly simple; it can take anywhere from an hour to a day or so, depending on anatomical complexity and image quality. For muscles, this is harder because the images are often more hazy and muscles tend to interweave with each other, segue into tiny tendons, take sudden turns through bones or other narrow spaces, or even fuse with other muscles. So when we do this kind of musculoskeletal modelling, it gets pretty laborious, and can take weeks or months to finish.

Ahh, but once you’re done with the basic anatomy, the real fun begins! We take the 3D images of bones, muscles, etc. and import them into our biomechanics software. We use two packages: one commericial item called SIMM (Software for Integrative Musculoskeletal Modeling) for making models, and a nice freebie called OpenSim for doing simulations (although actually we’re finding SIMM is often better at doing both modelling and simulation for more unusual animals). Quite a bit more anatomical work is required to get the joints to move properly, then position the muscles in accurate or at least realistic 3D paths (depending on segmented image quality), then check the muscles to ensure they move properly throughout the joints’ ranges of motion, then import all the PCSA and Fmax and other data we need from dissections, then do a lot more debugging of the model… this takes months, at least.

But the greatest joy and pain comes in getting the biomechanics done with the models and simulations. You can get quite simple data out of the models alone; such as the leverages (moment arms) of individual muscles and how these change with limb joint position, across a gait cycle, etc… That’s pretty interesting to us, and can just take a few days to crank out from a finished model. Yet the ultimate goal is to do either a tracking simulation, in which we make the model try to follow forces and motions that we measured in experiments from the same or a similar animal (standard, harmless gait analyses), or a theoretical simulation, in which we set the model a task and some rules (‘optimization criteria’) and then set it to run (for hours, days or weeks) to solve that task while following the rules. In both cases, the simulations estimate the muscle activation timings (on/off and intensity) and forces, as well as the kinematics (motions) and kinetics (forces) of the limbs. Then we check the results, play around with the inputs (unknown parameters) as part of a sensitivity analysis, and re-run the analyses again, and again, and again… Here is a draft of a tracking simulation we’ve run for our elephant’s hindlimb:

Above: again, a right hindlimb of an Asian elephant. This test of our tracking simulation is replicating real experimental data (from motion capture and force platform analysis) of an elephant running at near its top speed; over 4 meters/second (>10 mph/16kph). The red lines are the individual muscles, and the green arrow is the ground reaction force, equal and opposite to the force that the limb applies to the ground. In a fast elephant that force can exceed the elephant’s body weight, so the muscles need to crank out kilo-cheeseburger-units of force!

And that’s about as far as I’ll get today. My team’s previous research (explore links for some fun videos) has shown that elephants can run about 7 meters/second (~15mph; 24kph) and that they have pretty poor mechanical advantage when they do run, so their muscles must have to work pretty hard (about 6 times more cheeseburger units in a fast run vs. a slower walk). So how do they do it? And what prevents them from going faster? What would happen if they jumped? What limits speed more; muscles, tendons or bones? Stay tuned. I’m still not sure how much longer this final step of the research will take… (presumably will precede the heat death of the universe by a long shot) But overall, the whole process when everything works nicely can take a year or so to do, proceeding from whole limbs to a simulated limbs.

As a final teaser, here is work we’ve done on using a different kind of model, called finite element analysis (FEA), to estimate how many cheeseburgers it would take to break an elephant’s femur (thigh bone), for example. How “overbuilt” are bones vs. muscles or tendons? This is still a poorly resolved question in biology. We’ve established some rigorous methodology for doing this, now we just need to see what answers it gives us…

(the colour shows the strain (deformation) in the bone in a simple bending experiment; “hot” colours are higher strain. The visualization of the strain is greatly exaggerated; in the real results they are barely visible, as bone only bends a tiny amount before fracturing)

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