A History of Skeletal Drawings: Part 2 - Bone Wars to the 1950's

As we saw in Part 1, the 19th century saw the rise of many of the modern conventions we see in skeletal reconstructions.  Yet the last two decades of the century closed without any innovations, and at times a retreat from proportional accuracy.  In short, skeletal reconstructions became more schematic in nature.  Yet the creation of the modern silhouette skeletal reconstruction evolved in the first half of the 20th century. Why did skeletal drawings see an initial fall? And when did the modern form get invented?  Let’s take a look...

The Fall and Rise of Skeletal Restorations

Before we begin with the doom and gloom, I want to take care not to give off the wrong impression about the Bone Wars.  It was a fascinating and productive time in the history of paleontology, and the results were a treasure trove of fossils that still delight artists and scientists more than a century later.  Yet the time period had a chilling effect on the field of producing skeletal reconstructions.  Nobody outlines were put on skeletal reconstructions for decades, and the skeletals that were published often were erroneous in their general proportions.

(Marsh's Stegosaurus, sporting a bodacious mohawk)

So what happened?  There seem to have been several factors at play.  As the 19th century closed Europe was coping with the social, economic, and political issues that would eventually lead to WWI.  As intellectual giants like Cuvier and Owen died, scientists of similar calibre were not stepping into the field to replace them.  The U.S. on the other hand was rapidly pushing back their western boundaries post Civil War and was eager to demonstrate its growing scientific prowess.  With the increase in publications during the Bone Wars, the bulk  paleontology publications started to shift to North America.  The U.S. had a different (and shorter) set of academic traditions than Europe, and one area it lacked was in comparative anatomists.  Cope, for example, was very interested in evolutionary mechanisms (his 1897 book The Primary Factors of Organic Evolution is a fascinating insight into how trivialized natural selection had become to most biologists by the late 19th century), but he did not spend his free time dissecting modern animals to learn their soft tissue anatomy.

The specimens themselves were also frequently different, especially in their mode of preservation.  Many (though not all) of the fossils we looked at in Part 1 were of the type that are embedded in slabs, or otherwise excavated with their buried position largely intact.  The fossil finds at Como Bluff and Hell Creek were the opposite; they usually come out of the ground one bone at a time.  Quarry maps were a nascent field and not generally as precise as we see today.  It's also worth noting that most of the dinosaurs named during the bone wars were not actually mounted until midway through the first decade of the 20th century. All of these factors would have made it more difficult to judge and measure proportions.

Cope's Camarasaurus on the left, Compsognathus on the right. I admit it, Cope had it harder (images from here and here

So in short; both the fossils and the scientists that starred in the Bone Wars were very different from what had come before, and the results were less than satisfying skeletal reconstructions.  And it would take several decades before things would fully recover.

That’s not to say there weren’t skeletal reconstructions that were published.  But for the first couple decades they tended to resemble those popularized in the Marsh and Cope monographs.  Below are the first two published skeletal reconstructions of everyones favorite dinosaur,

Tyrannosaurus rex:

(Godzilla... I mean T. rex , from the 1905 and 1906 papers on the beast.) 

One significant change that did arise in the opening years of the 20th century was photos. Thanks to the relentless march of technology photographic cameras became more widely available to scientists (and their assistants) in the early 20th century.  As a result many of the monographs that traditionally would have included illustrated skeletal reconstructions instead sported photographs of the mounts.  An early example is Brown’s 1905 description of Champsosaurus.

(Not a stinkin' drawing, but at least it comes in two different views)

While the appearance of photography may have hindered the number of skeletal drawings executed, there were certainly benefits; individual bones could be represented more accurate (and eventually at less cost) than traditional plate illustrations. In the 1910s several skeletal reconstructions were made not from observation of the bones directly, but from projections made from photographs. Our good friend T. rex demonstrates this new fad in Osborn’s 1917 paper:

(Still posed like Godzilla, but the bones are proportionately accurate!)

Several classic skeletal reconstructions were published in the 1910s, including Brown’s 1914 “Monoclonius” and Lambe’s 1917 Gorgosaurus, but all looked eerily like those you see above.  In the highly productive 40 years of American paleontology that started with the Bone Wars very little was done to expand the boundaries of the formal skeletal drawing; in the end the largest innovation was to start using photographs as a way to get the proportions correct...as they had largely been before the Bone Wars.

Over in Europe there were a few hints of what might have been.  As discussed in Part 1, Seeley’s Dragons of the Air did contain modern looking skeletal reconstructions of pterosaurs (some with outlines) in 1901.   In 1909 Othenio Abel drew such a giant skeletal reconstruction with body outline for the Frankfurt Senckenberg Museum of Natural History to help the staff understand how the bones of Diplodocus went together.  The extremely colorful Baron Franz Nopcsa was taking an interest in the physiology of dinosaurs and would eventually contribute outlined skeletal reconstructions.

(From Ilja Nieuwland's The colossal stranger (1910) - kindly supplied by the author. Original published with kind permission by the Senckenberg Museum of Natural History, Frankfurt am Main, Germany)

Had the situation in Europe been more conducive to paleontology, perhaps we would have seen a continuation of the thought begun in the 19th century.  But it was not to be, and World War I put paleontology on the back burner for most of the decade.  Ideas must have been fomenting on both sides of the Atlantic, as almost immediately after the war we see a strong re-emergence of the outlined skeletal reconstruction, and widespread interest in paleobiology.  Nopcsa produced a remarkably wrong reconstruction of Tanystropheus, which he mistook to be a pterosaur relative and namedTribelesodon in 1922.   Heilman also contributed outlined skeletal drawings in his The Origin of Birds.  But the real champion of the Roaring ‘20s was Friedrich von Huene.   The entire decade was filled with his skeletal reconstructions; in addition to reviving the body outline, von Huene also demonstrated a  strong concern for proportional accuracy.  Some of his sauropods show a fairly modern feel.

(Huene's remarkably modern-lookingTitanosaurus skeletal reconstruction)

This time the United States was not totally left behind.  Richard Lull published what was probably the first American skeletal reconstruction with an outline in his 1921 redescription of Nodosaurus, and a couple of years later Gilmore did the same for his 1924 description of Stegoceras.

(Huene's Procompsognathus standing and crouching - note the style of the crouched illustration)

Alfred Romer made a different sort of contribution to the field, when he started to publish his systematic restorations of the muscles of extinct animals.  It’s easy to imagine his comparative anatomical work making the ghosts of Cuvier and Owen smile.  The idea of reconstructing muscles explicitly like this was mostly a haphazard affair for decades, but it was the sort of work necessary if the outlines around skeletons were ever to be more than artistic doodles.

(Romer's restoration of the thigh muscles of T. rex)

The 1930s saw the Great Depression, and with it a corresponding decrease in paleontological publications.  Once again attempts to scientifically restore the functional anatomy of dinosaurs stagnated.  In Lull’s 1933 Revision of the Ceratopsia there is a wealth of photographs and illustrations of fossils, but only a single skeletal reconstruction:

(The lone(ly) skeletal drawing in Lull's revised Ceratopsia monograph)

Von Huene continued to publish, but at a reduced rate.  Gilmore put out a landmark osteology on Apatosaurus, with a skeletal reconstruction reminiscent of the monographs of Cope and Marsh (which to some degree was probably intentional).  Loris Russell did a Romer-esque full-body muscle reconstruction of Chasmosaurus, but for the most part it was a lost decade.

(L. Russell's flayed Chasmosaurus, understandably cringing in terror)

World War II further depressed the rate of paleontological publications, yet what was published shows that things had started to perk up. In China C. C. Young showed he was influenced by Huene's skeletal reconstructions, although anatomically-speaking the outlines sometimes appeared to be afterthoughts.

(Well, at least he's trying - frome Young, 1942)

When Lull and Wright put out their monograph on hadrosaurs in 1942 it was in stark contrast to Lull’s ceratopsian monograph of the previous decade; it was chock full of skeletal reconstructions, including several illustrations by Nelda Wright that hearkened back to Huene's 1921 crouching Procompsognathus. She polished the idea, and the images were to directly influence the dinosaur renaissance in the 1970s. 

(Nelda Wright channels her inner von Huene)

In the mid 1940s came an event that would have massive influence down the road.  The famous paleoartist Charles R Knight put out a book called...well, actually there’s a bit of a small mystery there. Most everyone refers to the book as Animal Drawing: Anatomy and Action for Artists. But the hardback copy I have from 1947 is actually called Animal Anatomy & Psychology for the Artist and Layman. Really, here’s a scan of the cover:

See?

As near as I can tell the title that is common today was given to the reprints done in the 1950’s, and has carried over to the present.  Regardless, inside the book - which has nothing to do with prehistoric animals at all - are images that can amaze and astound us in the present.

(Chaz Knight's skeletal of an Asian elephant)

That’s right, full blown skeletal reconstructions with black silhouettes for the muscles was invented by none other than Charles Knight, paleoart superstar!

(More of Knights black-silhouetted skeletal drawings)

The book also contains many lovely drawings of the musculature of living animals.  Given the preeminent role played by Knight in the history of paleoart, the work in Drawing Animals seems both brilliantly ahead of its time and also a lost opportunity.  Romer had started to publish his muscle restorations of dinosaurs (and other extinct animals) in the 1920s - one can easily imagine a world where fully illustrated muscle reconstructions and black-silhouetted skeletal drawings of dinosaurs had been with us for 6 decades.  

Of course the marriage of Knights paleoart and his drawing conventions for living animals did not take place.  The Knight-look was first applied (with several variations) to paleontology by William Scheele in his 1954 book Prehistoric Animals.

(Scheele's Struthiomimus....sloooowly pushing off on its right foot)

At times Scheele seemed to be channeling a bit of Nelda Wright as well, as he experimented with different forms of outlined skeletal reconstructions throughout the book.

(Scheele's Ornitholestes, complete with eyeball (!) in the skull)

To understand how rapidly this unfolded, remember that from the 1880s to 1940 very modest progress was made with skeletal reconstructions.  Most came from Europe (and particularly from von Huene).  Perhaps the kindest thing that could be said 60 years after the Bone Wars began was that skeletal drawings had gotten back to the variety and accuracy seen leading up to the Bone Wars.  Yet during and immediately after WWII (despite an overall decrease in the number of paleo publications) we saw rapid innovation.  Outlined skeletal drawings show up on three different continents, new forms are invented and/or resurrected by Nelda Wright, Charles Knight, and those conventions are synthesized a little later William Scheele. 

What happened?  There is no obvious answer for this burst of creativity.  Knight had actually been moving away from paleoart after the death of Henry Fairfield Osborn in 1935.  It seems clear that Scheele was influenced by both Knight and Wright, but there are no direct records and now it's too late to ask anyone.  The rest of the 1950's played out fairly quietly. But the stage had been set for the great flowering of skeletal reconstructions we have today. In Part 3 we'll (finally) get to the modern period, and see how skeletal drawings were influenced by the Dinosaur Renaissance, and vice versa.

References:

Knights, C (1947) Animal Anatomy & Psychology for the Artist and Layman.

Rudwick, M.J.S. (1995) Scenes from Deep Time. University of Chicago Press, 294 pages.

Seeley, H.G. (1901) Dragons of the Air. William Brendon & Son, Plymouth.

A History of Skeletal Drawings: Part 1 (pre-20th century)

The ponderous creature you see above is Plateosaurus.  The skeletal reconstruction could probably be several posts in itself, but first I’d like to spend some time pondering how we got here.  No, no, I don’t mean what link you clicked on to reach my blog, but rather the larger journey taken by scientists and the scientific illustrators that collaborate with them.  We're going to spend lots of time dissecting modern skeletal reconstructions and laying out the do’s and don’ts of restoring extinct animals, but first it’s worth reviewing how we arrived at this juncture...

We are enjoying a true renaissance in reconstructing dinosaurs (and other extinct forms).  But every renaissance is rooted in a larger context, and given the discussion going on in our profession right now I think it behooves us to pause and look back at that history.  With a better understanding of how the modern form appeared we should also take a moment to gather ourselves and contemplate future of the format, and what can be done to best secure it (well, in Part 2 anyways).

The Beginning: Skeletal reconstructions prior to the 20th century

In terms of peoples' general awareness, I imagine we could sum up the origins of the modern skeletal drawing something like this:

In the beginning there was Bob Bakker, and he decided to reconstruct some skeletons against a black silhouette, and he saw that it was good.  On the second day he showed the format to Greg Paul, who took the format and multiplied it, and they saw that it was good.  And they told the other scientific illustrators to go forth and populate the field with reconstructions, and everyone saw that it was very good indeed.

Obviously both men made immense contributions to the field, and continue to popularize our modern conception of skeletal drawings, but they don't exist in a vacuum.  In fact, there are so many candidates for a discussion of where anatomical illustrations began that we need to set some ground rules in order to avoid a semester’s length art history lesson.  For example we could examine ancient anatomists, but (not surprisingly) they were largely concerned with human anatomy, for both medical and artistic reasons.  Many of these classical works are lost to us (as are as many of the anatomical works produced by Byzantine and Muslim researchers during medieval times) but the other problem is people aren't extinct.

(A Leonardo da Vinci skeletal reconstruction - Fatally flawed by its non-fossil subject matter.)

So instead let’s pick things up where paleontology gets involved.  While the modern field of comparative anatomy is usually traced to the 17th century, it wasn't until the late 18th century that Georges Cuvier added extinct animals into that equation...and after all, that’s what we’re here for, right?

As many of you are aware, Cuvier was the gentleman who demonstrated that, unlike diamonds, species don't last forever.  As head-bludgeoningly obvious as that may seem today, it was quite the intellectual coup in the late 1700s.  Flush with his success in establishing extinction, and excellent anatomist that he was Cuvier started to provide reconstructions of fossil animals fairly quickly.

(One of Cuvier's extinct elephants.)

It should be noted, however, that Cuvier was scooped in creating the first skeletal reconstruction of an extinct animal; that honor lies with Juan Bautista Bru, who did an illustration of a mount of a giant ground sloth in 1793 (later to be named Megatherium by Cuvier).

(The first Megatherium in a very stiff looking pose. Still, being the first ever skeletal reconstruction of an extinct animal we need to cut J. Bru some slack.)

And thus was established the basic idea of using a skeletal reconstruction to convey the anatomy of an extinct form.  Cuvier may not have originated the idea, but he clearly popularized it.  Modern conventions are evident even in these first attempts; the animals are posed in lateral view, and the pose is selected so as to better show off the anatomy and minimize parallax.  In the early 1800s Cuvier introduced a subtle refinement, the use of a human to show scale:

(From Cuvier's 1821 Théorie de la terre.)

The illustration forsakes true side view, but in exchange makes an attempt to convey the size of the animal to the reader. Cuvier also made the next conceptual leap in reconstructing skeletons - that of restoring an outline around the skeleton to suggest the life appearance of the animal. Sadly, this was an innovation he kept to himself; as lovingly detailed in the book Scenes from Deep Time Cuvier never published these illustrations out of fear that they would make his work seem too speculative.  Yet the unpublished skeletal reconstruction of Anoplotherium is so far ahead of its time it would not look out of place in a modern publication:

(Why Georges, why???)

Cuvier’s fear of damaging his scientific reputation meant someone else would have to introduce the concept of a body outline to skeletal reconstructions.  And as it turned out it there was a group of fossils that were ideal for inspiring the reconstruction of outlines: Pterosaurs.

When pterosaurs were first discovered paleontologists weren't quite sure what to think of them. The first fossils were mistakenly thought to be as from aquatic animals. Even as further discoveries clarified the anatomy of pterosaurs, the very idea of "flying reptiles" flew in the face of Victorian era assumptions of what a reptile was supposed to be. Cuvier, always a paleontological busy-body, was the first to suggest pterosaurs flew in 1801. This ignited a debate that would rage for several decades, and as a result reconstructions of the wings became Real Science (TM) as a way to demonstrate the flying hypothesis.

(Almost an outline!) 

In 1812 Samuel von Sömmerring did just this, providing a skeletal reconstruction that included his view of how the wings should be restored. While this isn't a full outline, the fact that pterosaurs had such extensive wing coverage means the it's largely just the head and neck that don't have an outline around them.

This debate was to rage on until the 1830s, and included several rounds of debate as to the proper way to restore the behavior and habitat of pterosaurs...but the important point for our story is that some of those scientists published the first complete outlines with their skeletal reconstructions, like Wagler's swimming Pterodactylus in 1830 (below).

(Not totally correct - but definitely an outline!)

It's worth noting that while Wagler was not correct about the aquatic habitat, the skeleton still shows great attention to the basics of proportion, and getting overall size and shape of the skeleton correct.

It's possible that restoring outlines around skeletal reconstructions could have remained a niche affair for pterosaur workers, but starting in the late 1840s Sir Richard Owen started to adopt the conventions and many of his vertebrate paleontology papers are teeming with outlined skeletals, like the Palaeotherium below:

Owen not only popularized the convention within scientific publications, but his work made an impression on the general public as well. Perhaps the most famous (and certainly one of the most lavish) example is Owen's skeletal reconstruction of Megalosaurus that served as a guide for sculptor Waterhouse Hawkins when he created the famous sculptures at the Crystal Palace.  The illustration is not only one of the earliest dinosaur skeletal reconstructions, it also is one of the first to have the good sense to indicate which bones are actually preserved (in this case, not too many!).

At a time when Darwin was still mulling over his abstract on the impermanence of species, many of the tenets of modern skeletal reconstructions had become widespread.  Darwin’s friend and bulldog Thomas Henry Huxley actually produced one of the first modern-looking dinosaur skeletals in his 1876 work defending evolution in Popular Science Monthly.

(Huxley's 1876 reconstruction of Compsognathus)

So 3/4s of the way through the 19th century it was common to provide skeletal reconstructions of extinct animals.  They were done habitually in side view, great care was paid to reconstructing the proportions of the animals, and there was lively variety in terms of providing scale and conveying the completeness of a specimen.  At this point I feel we could have expected ever more refined attempts at reconstructing skeletons, but a funny thing happened: war broke out.

The great bone wars of North American lead to a then unimaginable treasure troves of dinosaur fossils, and subsequently many important additions to our knowledge of dinosaur anatomy and diversity.  Yet it also lead to stagnation in the portrayal of skeletal reconstructions, and even a move backwards away from accuracy.  The great monographs of Cope and Marsh are often viewed as a sort of golden age in pure descriptive paleontology.  They are filled with dozens of plates of individual bones rendered at great time and expense.  Yet gone are the attempts to place an accurate outline around skeletons; the skeletal drawings themselves are often careless with the number of vertebrae restored and are generally less accurate in capturing the actual proportions of the animals they represent.

With a few notable exceptions (i.e. the Scaphognathus in Seeley’s popular book Dragons of the Air) the business of trying to reconstruct dinosaurs would have to wait until after WW1. And that is where we'll pick up in part two, as we trace the fall and rise of the modern skeletal reconstruction across the 20th century, and up to the present.

(From Dragons of the Air, 1901, page 163.)

References:

Cuvier, G. (1821) Théorie de la terre.

Cuvier, G. (1825) Recherches sur les ossemens fossiles, vol. 1, p. 248.

Huxley, T.H. (1876) Professor Huxley's Lectures I. Popular Science Monthly, vol. 10, November.

Owen: R. (1860) Palaeontology: or A systematic summary of extinct animals and their geological relations. A. & C. Black. 420 pages.

Rudwick, M.J.S. (1995) Scenes from Deep Time. University of Chicago Press, 294 pages.

Seeley, H.G. (1901) Dragons of the Air. William Brendon & Son, Plymouth.

Note: I'd like to thank Mike Hansen, who drew my attention to the role that pterosaur skeletal reconstructions played in the origin of body outlines. You can see his DeviantArt page here.

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T. rex: "Baby got back"

A few months ago Scott Persons and Phil Currie published a paper that clarified the shape of the tail of T. rex.  It's a paper I'm fond of, in part because I did a reconstruction for it.  No, I'm not going to post it here; it's already staring at you from the banner of this blog.

 In the paper, Persons and Currie did some comparative anatomical sleuthing to better understand the size and shape of the caudofemoralis muscle in tyrannosaurs.  For those of you who aren't familiar with the caudofemoralis muscle, it runs down much of the tail and inserts on the femur; when the muscle contracts, it pulls the leg back.  This makes it a Very Important Muscle (TM).  If you are adventurous (or just happen to live in Louisiana) it's worth noting that if you eat alligator meat, this is the part you usually end up eating.

Their paper demonstrated that many scientists and paleoartists have been underestimating the size of the caudofemoralis by a wide margin.  As a result artists were reconstructing the tail incorrectly.  Here for example is an Allosaurus (drawn bysome yahoo) that has a tail that is too skinny.

In that yahoo's defense, the image is almost 15 years old.  But you can still see many examples of this sort of tail reconstruction in paleo-art published today.

So how are we to fix it?  The P&C paper came with a lovely diagram showing the cross-sectional anatomy of an alligator tail:

(From Persons & Currie, 2010)

Unfortunately, alligators don't have tail vertebrae with the same proportions as a T. rex.  That's not really a surprise (alligators are aquatic after all) but it might make it more difficult to visualize a tyrannosaur tail in cross-section.  So without further ado, here is a quick visual reference on how to do this in tyrannosaurs:

The red muscle is the caudofemoralis.  It starts out fairly small, but as it gets closer to the base of the tail it expands greatly, pushing the other muscles in the tail out of the way in the process.  As it enters the leg (below most of the leg muscles) it joins another head of the caudofemoralis (yellow) that actually originates from a shelf on the upper hip bone (the illium).

This model of tail muscles probably applies to almost any dinosaur that doesn't have an absurdly reduced tail (birds, I'm looking at you!).  And the greater amount of muscle would better power dinosaurs into all of those gee-whiz activities people like to draw them in.  So I guess my advice to paleoartists in this case is: "cover your butt".

Reference:

Persons, W., & Currie, P. (2010). The Tail of Tyrannosaurus: Reassessing the Size and Locomotive Importance of the M. caudofemoralis in Non-Avian Theropods. The Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology DOI: 10.1002/ar.21290

Welcome to the official Skeletal Drawing.com Blog!

For the first installment, let's get the the five W's out of the way:

Who:

For those of you who don't know me, my name is Scott Hartman.  You can read more about my research, interests, and other exploits here.

What:

This blog will deal with the functional anatomy of dinosaurs and other extinct critters.  In addition to exploring what is known about the anatomy and appearance of extinct animals, an emphasis will be given as to how we know, as well as the limits on what can be confidently restored in extinct animals.

Why:

Blogging turns to be the perfect medium for recurring articles on a similar theme.  Almost like they were designed that way.  Also, all the cool kids seem to be blogging these days, and no one wants to be last to the party!

Where:

I hope to integrate the blog even more seamlessly with my website and other content, but for now it's available directly at: http://skeletaldrawing.blogspot.com/, or indirectly from my website: www.skeletaldrawing.com/.

How (often):

You can expect to see frequent updates.  At least weekly, but perhaps more often as topics and schedule allow.

And now, for a skeletal reconstruction:

That's Silesaurus opolensis, an "almost dinosaur" from Poland.  I'll probably have more to say about it (and why it appears to not quite count as a dinosaur) in a future post, but in the meantime if you're interested you can read a bit more about it at the Silesaurus entry on Wikipedia, which is pretty decent.

The format of the blog is not set in stone, so I welcome your suggestions and feedback!