Tag Archives: fossils

Dinosaurs on display in 2014

Instead of repeating last year’s navel-gazing, I’m going to try something a little more interesting with my obligatory year-in-review*. This post will recap 2014’s big events in museum paleontology – I’ve covered some of it before, but there’s plenty that I missed as well.

Out with the Old

artists conception

Concept art for the new NMNH fossil hall, opening 2019.

I don’t think it’s a stretch to say that the most important event in the world of fossil exhibits this year was the closing of the National Museum of Natural History’s east wing. This is the world’s most-visited natural history museum, and the fossil mounts on display here have been among the most widely-viewed anywhere. The east wing has been home to paleontology displays since the building opened more than a century ago, but until now it has never undergone a complete, wall-to-wall modernization. Since the halls closed in April, NMNH staff have made significant progress de-installing the old displays, including some mounted skeletons that have been on display for over 80 years. Over the next five years, this historic space will be restored to it’s original neo-classical glory, and eventually remade into a new chronicle of the history of life on Earth suitable for the 21st century.

NMNH was among the last of the classic American natural history museums to commit to a post-dinosaur renaissance overhaul (the American Museum of Natural History started the trend in 1995, followed by the Field Museum and the Carnegie Museum). All eyes are now on the Peabody Museum of Natural History, where the great hall of fossil reptiles still looks much as it did sixty years ago. A plan is in place for a $30 million renovation, and the museum is currently soliciting donations to fund the project. For now, however, New Haven is one of the last places in North America where visitors can still see early-20th century dinosaur mounts.

In With the New

Spinosaurus!

Spinosaurus at the National Geographic Explorer’s Hall. Photo by the author.

Several new temporary and traveling fossil exhibits opened in the United States this year. The biggest splash was made by “Spinosaurus: Lost Giant of the Cretaceous”, which I reviewed in September. Premiering at the National Geographic Explorer’s Hall in Washington DC, this exhibit is science outreach on a grand scale. It debuted alongside a technical paper by Nizar Ibrahim and colleagues that redescribed the well-known Spinosaurus as a short-legged analogue to early whales. While there has been some skepticism about the paper’s conclusions, credit must be given for such an ambitious public display of up-to-the-minute research. The exhibit, which includes a 50-foot reconstruction of a swimming Spinosaurus skeleton, will be on display in Washington through April 12. After that, it begins its world tour in Germany.

Washington, DC got a second new paleontology exhibit this Fall in the form of “The Last American Dinosaurs” at NMNH. Focusing on the North American ecosystem that existed just before the Cretaceous-Paleogene extinction event, this exhibit will serve as an interim dinosaur attraction while the main fossil hall is being renovated. The Last American Dinosaurs is more than a stopgap, however – it’s a remarkably well-crafted look at ecology and the phenomenon of extinction, both in the past and in the present.

Other 2014 fossil exhibits of note include “Tiny Titans: Dinosaur Eggs and Babies” at the Peabody Museum, and “Pterosaurs: Flight in the Age of Dinosaurs” at AMNH. Tiny Titans didn’t feature any show-stopping fossil mounts, but it was nevertheless a charming, kid-friendly exhibit focused on how different groups of dinosaurs raised their young. I thoroughly enjoyed it, particularly the gorgeous artwork by Luis Rey. I missed my chance to check out Pterosaurs (it closes this week), so if you were able to see it please share your thoughts!

Mount of the Year

Sophie the Stegosaurus at the Natural History Museum in London. Source

Sophie the Stegosaurus at the Natural History Museum in London. Source

What was the coolest mounted fossil skeleton created this year? For the runner up, I’d pick the aforementioned Spinosaurus. Created by RCI and Acme Design under the direction of Paul Sereno’s lab at the University of Chicago, this replica skeleton embodies both the possibilities and pitfalls of digital technology. The Spinosaurus mount is based on a digital composite of laser-scanned fossils held in at least three countries, as well as scaled-up bones from related animals like Suchomimus, and a fair amount of sculpted material. On one hand, it’s incredible that a unified vision of this animal can be willed into three-dimensional existence. However, one could reasonably voice concern about presenting a somewhat controversial hypothesis in a format that implies authenticity. Virtually all fossil mounts are composites to some degree, but it seems we’re still working out the limits of how far this concept can be taken.

In contrast, I have no reservations in granting Mount of the Year to Sophie the Stegosaurus. Unveiled on December 4th at London’s Natural History Museum, this is the most complete Stegosaurus specimen known and the first example of this species to be displayed in Europe. It’s also the first new dinosaur skeleton to be added to historic NHM exhibit halls in more than a century. After the museum purchased the skeleton from a private dealer in 2013, Paul Barrett and Charlotte Brassey have been carefully examining (and laser-scanning) every inch of it for the better part of the last year. New data on the biomechanics and behavior of Stegosaurus is due out soon, but for now the public can enjoy the 18-foot skeleton in a dramatic display at the museum. In addition to the impressive work creating a dynamic pose with nearly invisible supports, I’m particularly taken by NHM’s outreach efforts, which explain the importance of this skeleton for a broad range of audiences.

All in all, 2014 was a pretty good year for paleontology on display. While fossil exhibits remained stagnant for much of the 20th century, the last decade plus has seen an explosion of displays to feed the public’s insatiable appetite for dinosaurs. Perhaps in the future we will call this time the second golden age of fossil mounts!

*For the record, Dinosours! got about 26,000 visitors last year, many of which I owe to the good people at Love in the Time of Chasmosaurs and SV-POW. My review of the Spinosaurus exhibit was by far the most popular post, followed by the two-parter on Triceratops posture and the true story of the mismatched “Brontosaurus” skull.

 

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Filed under AMNH, dinosaurs, exhibits, fossil mounts, museums, NMNH, opinion, theropods, thyreophorans

Displaying the Tyrant King – Part 2

Old meets new

Old meets new: The classic Carnegie T. rex (CM 9380) is now paired with a cast of Peck’s Rex (MOR 980). Photo by the author.

Start with Displaying the Tyrant King – Part 1.

In 1915, the American Museum of Natural History unveiled the first mounted skeleton of Tyrannosaurus rex ever constructed. The Carnegie Museum of Natural History followed suit with their Tyrannosaurus mount in 1941, and for most of the 20th century New York and Pittsburgh were the only places in the world where the tyrant king could be seen in person. Nevertheless, these displays propelled Tyrannosaurus to universal stardom, and the instantly recognizable dinosaur appeared in countless books, films, and other media for years to come.

The omnipresence of T. rex was secured in part by two additional museum displays, ironically at institutions that did not have any actual Tyrannosaurus fossils on hand. The Field Museum of Natural History commissioned Charles Knight to paint a series of prehistoric landscapes in 1928, the most recognizable of which depicts a face-off between Triceratops and a surprisingly spry Tyrannosaurus. In 1947, Rudolph Zallinger painted a considerably more bloated and lethargic T. rex as part of his Age of Reptiles mural at the Peabody Museum of Natural History. Both paintings would be endlessly replicated for decades, and would go on to define the prehistoric predator in the public imagination.

Rex Renaissance

Despite enduring public enthusiasm, scientific interest in dinosaurs declined sharply in the mid-20th century, and new discoveries were few and far between. This changed rather suddenly with the onset of the “dinosaur renaissance” in the 1970s and 80s, which brought renewed energy to the discipline in the wake of evidence that dinosaurs had been energetic and socially sophisticated animals. The next generation of paleontologists endeavored to look at fossils in new ways to understand dinosaur behavior, biomechanics, ontogeny, and ecology. Tyrannosaurus was central to the new wave of research, and has been the subject of hundreds of scientific papers since 1980. More interest brought more fossil hunters into the American west, leading to an unprecedented expansion in known Tyrannosaurus fossils. Once considered vanishingly rare, Tyrannosaurus is now known from over 50 individual specimens across a wide range of ages and sizes. Extensive research on growth rate, cellular structure, sexual dimorphism, speed, and energetics, to name but a few topics, has turned T. rex into a veritable model organism among dinosaurs.

RTMP 81.6.1, aka Black Beauty, mounted in relief at the Royal Tyrell Museum. Source.

RTMP 81.6.1, aka Black Beauty, mounted in relief at the Royal Tyrell Museum. Source

The most celebrated Tyrannosaurus find from the early years of the dinosaur renaissance came from Alberta, making it the northernmost and westernmost T. rex to date. The 30% complete “Black Beauty” specimen, so named for the black luster of the fossilized bones, was found in 1980 by a high school student and was excavated by paleontologist Phil Curie. The original Black Beauty fossils were taken on a tour of Asia before finding a permanent home at the newly established Royal Tyrell Museum in Drumheller, Alberta. In lieu of a standing mount, Black Beauty was embedded in a faux sandstone facade, mirroring the environment in which the fossils were found and the animal’s presumed death pose. This relief mount set Black Beauty apart from its AMNH and CMNH predecessors, and even today it remains one of the most visually striking Tyrannosaurus displays.  Since the original specimen consisted of less than half of a skeleton, much of this display is made up of sculpted bones, including the pelvis, scapula, and most of the ribs. The mounted skull is a cast, but the real skull is displayed behind glass nearby. A complete cast of Black Beauty in a traditional free-standing mount is also on display at the Swedish Museum of Natural History in Stockholm.

The World’s Most Replicated Dinosaur

Driven by the increased public demand for dinosaurs, many museums without Tyrannosaurus fossils of their own have purchased complete casts from other institutions. In 1986, the Academy of Natural Sciences in Philadelphia opened “Discovering Dinosaurs”, the world’s first major exhibit showcasing active, endothermic dinosaurs. The centerpiece of the exhibit was a cast of the original AMNH Tyrannosaurus, posed for the first time in the horizontal posture that we now know was the animal’s habitual stance. The following year, another AMNH cast appeared in the lobby of Denver Museum of Nature and Science in a strikingly bizarre pose, with one leg kicking high in the air. The mount’s designer Robert Bakker intended to push boundaries and demonstrate what a dynamic and energetic Tyrannosaurus might be capable of, although the mount has subsequently been described as dancing, kicking a soccer ball, or peeing on a fire hydrant. Meanwhile, The Royal Tyrell Museum prepared a mount of RTMP.81.12.1 (a specimen consisting of a relatively small number of postcranial bones) that was filled in with AMNH casts, including the highly recognizable skull.

Cast

Tyrannosaurus cast at the Denver Museum of Nature and Science. Source

Since the late 1990s, however, casts of another specimen have overtaken AMNH 5027 for the title of most ubiquitous T. rex. BHI 3033, more commonly known as Stan, was excavated in South Dakota in 1992 by the Black Hills Institute, a for-profit outfit specializing in excavating, preparing, and mounting fossils. Stan is significant for being over two-thirds complete and for including the best-preserved Tyrannosaurus skull yet found. BHI has sold dozens of casts of the Stan skeleton to museums and other venues around the world. At a relatively affordable $100,000 plus shipping, even small local museums and the occasional wealthy individual can now own a Tyrannosaurus mount. With over 50 casts sold as of 2017, Stan is, by a wide margin, the most duplicated and most exhibited dinosaur in the world.

Stan the Tyrannosaurus at the National Museum of Natural History. Photo by the author.

Stan the Tyrannosaurus at the National Museum of Natural History. Photo by the author.

All these new Tyrannosaurus mounts are forcing museums to get creative, whether they are displaying casts or original fossils. Predator-prey pairings are a popular display choice: for example, the Houston Museum of Natural Science T. rex is positioned alongside an armored Denversaurus, and the Los Angeles Natural History Museum matches the tyrant dinosaur with its eternal enemy, Triceratops. Meanwhile, the growing number of juvenile Tyrannosaurus specimens has allowed for family group displays. A second T. rex exhibit at LACM features an adult, subadult and baby, while the Children’s Museum of Indianapolis pairs a Stan cast with the original skeleton of Bucky, a “teenage” T. rex. The most unique Tyrannosaurus mount so far is certainly the copulating pair at the Jurassic Museum of Asturias.

Tyrannosaurus versus Denversaurus at the Houston Museum of Nature and Science. Photo by the author.

Each of these displays gives a substantially different impression of Tyrannosaurus. Depending on the mount, visitors might see T. rex as a powerful brute, a fast and agile hunter, or a nurturing parent (or a gentle lover). Each mount is accurate insofar that a real Tyrannosaurus probably adopted a similar stance at some point, but the museum’s choice of pose nevertheless influences visitors’ understanding of and attitude toward the dinosaur.

Restoring the Classics

With dozens of new Tyrannosaurus mounts springing up across the country and around the world, the original AMNH and CMNH displays began to look increasingly obsolete. Unfortunately, modernizing historic fossil mounts is an extremely complex and expensive process. The early 20th century technicians that built these displays generally intended for them to be permanent: bolts were drilled directly into the bones and gaps were sealed with plaster that can only be removed by manually chipping it away. What’s more, the cumulative effects of rusting armatures, fluctuating humidity, and vibration from passing crowds have considerably damaged historic mounts over the course of their decades on display.

AMNH 5027 was restored and remounted in 1995.

AMNH 5027 was restored and remounted in 1995. Photo by the author.

Despite these challenges, AMNH and CMNH have both been able to restore and update their classic Tyrannosaurus displays. While fossil mounts used to be built in-house, often by the same people who found and described those fossils, modern mounting projects are typically outsourced to specialist companies. Phil Fraley Productions, an exhibit fabrication company based in the Pittsburgh suburbs, was responsible for both T. rex restorations. At AMNH, Jeanne Kelly spent two years disarticulating and conserving each bone before Phil Fraley’s crew took over to build the new armature. The new mount not only corrected the dinosaur’s posture, but improved visitors’ view of the fossils by removing obstructive vertical supports. Instead, most of the skeleton’s weight is now supported by steel cables hanging from the ceiling.  Each bone is secured to an individual metal bracket, allowing researchers to easily remove elements for study as necessary. A new cast of the skull was also prepared, this time with open fenestrae for a more natural appearance. Rather than attempting to match the dramatic and showy T. rex mounts at other museums, the AMNH team chose a comparatively subdued stalking pose. A closed mouth and subtly raised left foot convey a quiet dignity befitting this historically significant display.

Historically, the 1941 CMNH Tyrannosaurus had never quite lived up to its New York predecessor. Although it incorporated the Tyrannosaurus type specimen, it was mostly composed of casts from the New York skeleton, and it sported an unfortunately crude replica skull. It is therefore ironic that CMNH now exhibits the more spectacular T. rex display, one which finally realizes Osborn’s ambitious plan to construct an epic confrontation between two of the giant predators. As they had with the AMNH mount, Phil Fraley’s team dismantled the original display and painstakingly removed many layers of paint, shellac, and plaster from the bones. Michael Holland contributed a new restored skull, actually a composite of several Tyrannosaurus skulls. The restored holotype T. rex now faces off with a cast of “Peck’s Rex”, a specimen recovered from Montana in 1997. Despite the difficulty of modernizing the historic specimen, the team reportedly developed a healthy respect for turn of the century mount-makers like Adam Hermann and Arthur Coggeshall, who developed the techniques for making enduring displays of fragile fossils that are still being refined today.

Continue to Displaying the Tyrant King Part 3.

References

Colbert, E.H., Gillette, D.D. and Molnar, R.N. “North American Dinosaur Hunters.” The Complete Dinosaur, Second Edition. Brett-Surman, M.K., Holtz, T.R. and Farlow, J.O., eds.Bloomington, IN: Indiana University Press.

Dingus, L. 1996. Next of Kin: Great Fossils at the American Museum of Natural History. New York, NY: Rizzoli International Publications, Inc.

Johnson, K. and Stucky, R.K. 2013. “Paleontology: Discovering the Ancient History of the American West.” Denver Museum of Nature and Science Annals, No. 4.

Larson, N. 2008. “One Hundred Years of Tyrannosaurus rex: The Skeletons.” Tyrannosaurus rex, The Tyrant King. Larson, Peter and Carpenter, Kenneth, eds. Bloomington, IN: Indiana University Press.

Naish, D. 2009. The Great Dinosaur Discoveries. Berkeley, CA: University of California Press.

Norell, M., Gaffney, E.S. and Dingus, L. 1995. Discovering Dinosaurs: Evolution, Extinction, and the Lessons of Prehistory.  Berkeley, CA: University of California Press.

Psihoyos, L. 1994. Hunting Dinosaurs. New York, NY: Random House, Inc.

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Filed under AMNH, CMNH, dinosaurs, fossil mounts, history of science, museums, NMNH, paleoart, reptiles, theropods

What’s the deal with Astrodon?

In Laurel, Maryland, a trail of banners depicting a herd of the sauropod dinosaur Astrodon johnstoni leads the way to Dinosaur Park, the site of a historically significant fossil deposit. At the Maryland Science Center in Baltimore, a life-sized Astrodon sculpture towers over the “Dinosaur Mysteries” exhibit. And since 1998, Astrodon has been the official state dinosaur of Maryland, joining other state symbols like the black-eyed susan and Baltimore oriole. In short, Astrodon is a sort of mascot for mid-Atlantic paleontology. Named in 1858 for fossils found in a Prince George’s County iron mine, the appeal of Astrodon for Marylanders is obvious: it’s a home-grown dinosaur in a region that is not widely recognized for its fossil resources, and the story of its discovery also calls attention to the state’s industrial heritage.

But what sort of animal was Astrodon, and how much do paleontologists truly know about it? Compared to many other extinct animals found around the world, the fossil record for Astrodon is and always has been fairly poor. The name Astrodon was first bestowed upon nothing more than isolated teeth, and although other fragmentary remains attributed to Astrodon have been uncovered over the past 150 years, reconstructions of the Maryland sauropod are mostly derived from the fossils of relatives found elsewhere. What’s more, the name Astrodon has a convoluted history, having been applied haphazardly to fossils found across the country and even around the world. For these reasons, some paleontologists would prefer that the name Astrodon not be used at all.

Lacking a scientific consensus on what sort of animal the Maryland sauropod was or even what it should be called, I find myself in a difficult position as an educator. How can the messy and contentious taxonomy of Astrodon be condensed into something teachable? Is simplifying or downplaying this controversy doing our audience a disservice, and to what degree?

The taxonomic history of Astrodon

The first scientifically recognized North American dinosaur fossils were found in the Mid-Atlantic region, a scant 17 years after dinosaurs were first recognized as a biological group in 1842. Joseph Leidy’s Hadrosaurus from the New Jersey coast is credited as the first American dinosaur to be described, but Astrodon was a close second. During the mid-19th century, iron mining was big business in central Maryland. Miners extracted large boulders of siderite, or iron ore, from open pit mines throughout Prince George’s County, and these miners were the first in the region to discover dinosaur bones and teeth. The siderite was being mined from clay deposits now known as the Arundel Formation, part of the larger Potomac Group that extends throughout Maryland (the Potomac Group was laid down during the Early Cretaceous period, between 125 and 113 million years ago). Members of the Maryland Academy of Sciences recognized the fossils from the Arundel clay as similar to the English fossil reptiles that Richard Owen had recently unified as Dinosauria. In 1858, academy member Christopher Johnston published a description of a set of teeth from the iron mines in the American Journal of Dental Science, which he named “Astrodon” (Joseph Leidy turned this informal name into a proper binomial, Astrodon johnstoni, in his 1865 review of North American fossil reptiles).

Today, most paleontologists consider it poor judgment to name a new taxon based only on teeth. When scientists describe a newly discovered organism, they designate a type specimen, which is used to define that taxon in perpetuity. But when the type specimen is especially fragmentary, or only consists of a small part of the organism, it poses a problem for future researchers. In the case of Astrodon, no newly discovered fossils other than teeth can be confidently referred to the same species. In 1858, however, paleontological norms were very different. All dinosaur fossils known at the time were exceedingly incomplete: scientists knew that dinosaurs were reptiles and that they were very big and not much else. Any new fossils, even teeth, represented a major addition to our understanding of the life appearance and diversity of these extinct animals. For modern paleontologists, Johnston’s published description of the Astrodon teeth is vague and uninformative, but in his day, these fossils were distinct from anything else yet known.

Astrodon teeth lower left.

Astrodon teeth are on the lower left.

In December of 1887, famed paleontologist Othneil Charles Marsh sent his best fossil hunter, John Bell Hatcher, to search the area in Prince George’s County where Astrodon was discovered. Judging from Hatcher’s journal entries, he didn’t have a great time. It rained and snowed almost constantly, and on several days his team didn’t bother to show up for work. Although Hatcher managed to find numerous dinosaur, crocodile and turtle fossils, these finds did not match the quality of the fossils Hatcher had been finding in the western states, and no return trips were made. Nevertheless, Marsh saw fit to name two new dinosaur species from the material Hatcher collected: Pluerocoelus altus and Pluerocoelus nanus. Neither taxon was named for material that would be considered diagnostic if found today: P. altus was based on a tibia and fibula, while P. nanus was based on four nonadjacent vertebrae.

By this time, more complete dinosaur fossils from the American west were beginning to reveal a clearer picture of dinosaur diversity. Based on the shape and size of the fossils collected by Hatcher, Marsh determined that they belonged to sauropods, the group of long-necked herbivores that includes Diplodocus and Apatosaurus. More specifically, Marsh recognized that the Arundel sauropods were similar to “Morosaurus” (now called Camarasaurus) from Colorado. Today, the lineage of stocky, broad-nosed sauropods that includes Camarasaurus and its closest relatives are called macronarians. Unfortunately, by modern standards Marsh’s descriptions of P. altus and P. nanus are rudimentary in nature, and no distinguishing characteristics not common to all macronarian sauropods were offered.

Pleurocoelus elements. Image from NMNH Backyard Dinosaurs.

Pleurocoelus (or Astrodon?) fossils collected by Hatcher. Image from NMNH online exhibit Backyard Dinosaurs.

Contra Marsh, Hatcher suspected that there was only one sauropod in the Arundel Formation. P. altus and P. nanus were probably growth stages of one species, and the Astrodon teeth, now recognized as typical of macronarians, probably came from the same animal, as well. Since the International Code of Zoological Nomenclature decrees that the first published name given to a taxon has priority, Astrodon would take precedence over Pluerocoelus. Later, Charles Gilmore published a review of the Arundel fossils, in which he concurred with Hatcher that P. altus was a junior synonym of Astrodon, but retained P. nanus as a separate species.  

Then things started getting really complicated. While paleontologists were still debating how many sauropod species existed in the Arundel clay, Marsh and others had started naming lots of new species of Pluerocoelus. Fossils found in Texas, Oklahoma and even the U.K. were all thrown into the Pluerocoelus bucket, including P. montanusP. valdensisP. becklesii and P. suffosus. For much of the 20th century, Pluerocoelus was a classic wastebasket taxon, into which any and all sauropod fossils from early Cretaceous strata were casually thrown. Since the Pluerocoelus type specimens designated by Marsh were insufficient to define the taxon based on morphology, the name became little more than a temporal marker. Adding to the confusion, researchers continued to disagree over whether all these new Pluerocoelus species should be sunk into the earlier genus Astrodon.

In recent years, some progress has been made toward untangling this mess of early Cretaceous sauropods. There is a general consensus that fossils not found in Maryland’s Potomac Group differ substantially from the Arundel sauropods and should never have been referred to Pluerocoelus or Astrodon. New names have been proposed for the midwestern sauropods, including Astrophocaudia and Paluxysaurus. However, removing the non-Maryland fossils from the discussion merely returns us to the original set of problems: how many sauropods are represented in the Arundel clay, what were they like in life, and what should we call them?

Creating a coherent picture of Astrodon

Unfortunately, the answers to these questions depend on who you ask. The most thorough review of Arundel sauropods from the last decade was published by Kenneth Carpenter and Virginia Tidwell in 2005. Carpenter and Tidwell reaffirmed Hatcher’s conclusion that Pluerocoelus is synonymous with Astrodon, and that as the earliest published name, Astrodon has priority. This decision is apparently based only on the fact that the fossils came from the same stratum, however, since the Astrodon holotype cannot be compared to anything besides other teeth. For this reason, Michael D’Emic proposed in 2012 that the names Astrodon and Pluerocoelus are nomen dubia and should both be dropped entirely. Ultimately, neither solution is practical for identifying the sauropod fossils that continue to be collected from the Arundel Formation. Either we blindly refer any and all sauropod fossils to Astrodon, even though we lack a usable holotype, or we have no label available at all.  One solution would be to establish a new type specimen (called a neotype) for Astrodon, but this has yet to be done.

Both camarasaur and brachiosaur shaped Astrodon reconstructions are equally reasonable.

Both camarasaur and brachiosaur-shaped Astrodon reconstructions are reasonable. Artwork by Dmitry Bogdanov, via Wikipedia.

While many more sauropod fossils have been found in the Arundel clay since Hatcher’s 1887 expedition, we do not have enough material to fully elucidate what these animals looked like. Size estimates have varied enormously, from as little as 30 feet to as much as 80 feet in length. The assortment of fossil bones and teeth that have been found tell us we have a macronarian sauropod, and we can reconstruct its general shape based on more completely known relatives. However, macronarians were a fairly diverse bunch, ranging from the comparatively stocky camarasaurs to high-shouldered, elongate brachiosaurs. Carpenter and Tidwell describe the Arundel sauropod fossils, particularly the limb bones, as being fairly slender, but still more robust than those of Brachiosaurus. They do recognize, however, that nearly all known Arundel sauropod fossils come from juveniles, which may vary proportionally from adults. Because the precise affinities of Astrodon are unclear, artistic reconstructions vary substantially. The National Museum of Natural History’s Backyard Dinosaurs exhibit and website shows a camarasaur-shaped sauropod, while the life-sized sculpture at the Maryland Science Center is based on the brachiosaur Giraffatitan. At Dinosaur Park in Laurel, meanwhile, both versions are on display. More fossils, ideally cervical vertebrae or more complete adult material, are needed to clarify what the Arundel sauropod looked really like.

Teaching Astrodon

When I show people the teeth and partial bones attributed to Astrodon during public programs, I am almost always asked, “if that’s all you’ve found, how do you know what the whole animal looked like?”  As demonstrated by this post, it takes 1,700 words and counting to give a proper answer, which is too much for all but the most dedicated audiences. Nevertheless, to do anything less is to skip crucial caveats and information. Scientists are choosy about the words they use, filling explanations with “probablys” and “almost certainlys”, but they do so with good reason: when one’s job is to create and communicate knowledge, there is no room for ambiguity about what is and is not known. It is therefore just a bit dishonest to say that a large sauropod called Astrodon that was related to Brachiosaurus lived in Maryland, and yet I do so every week. How can I possibly sleep at night?

I’ll admit it can be difficult, but I get by because using one proviso-free name for the Maryland sauropod seems to be  informative and helpful to my audience. I only have people’s attention for so long, and I’d rather not spend that time on tangents about how Astrodon should really be called Pluerocoelus or why my use of either name is imprecise and problematic. I want visitors to walk away understanding how paleontologists assemble clues from sedimentary structures and anatomical comparisons to reconstruct ancient environments and their inhabitants. I’d like for visitors to practice making observations and drawing conclusions, and understand how paleontology is a meticulous science that can be relevant to their lives. “Paleontologists are weirdly obsessed with changing names” is not one of the most important things to know about paleontology.

Taxonomy, the science of naming and identifying living things, is unquestionably valuable. Biologists would be lost without the ability to differentiate among taxa. From my perspective, however, the public face of paleontology tends to overemphasize taxonomic debates in lieu of more informative discussions. There will always be somebody willing to argue whether Tarbosaurus bataar should be sunk into Tyrannosaurus, or to give incorrect explanations for why we lost “Brontosaurus.” In the end, though, these debates have more to do with people’s preferences than the actual biology of these animals. Astrodon may not be a diagnostic taxon in the strictest sense, but we need to call our fossils something, and taxonomic labels exist to be informative and useful. If asked, I’m always happy to provide the full story. But for the time being, Astrodon seems to be working just fine.

References

Carpenter, K. and Tidwell, V. 2005. Reassessment of the Early Cretaceous sauropod Astrodon johnstoni Leidy 1865 (Titanosauriformes). In Carpenter and Tidwell (eds.), Thunder-Lizards: The Sauropodomorph Dinosaurs. Bloomington, IA: Indiana University Press.

D’Emic M.D. 2012. Revision of the sauropod dinosaurs of the Lower Cretaceous Trinity Group, southern USA, with the description of a new genus. Journal of Systematic Paleontology, iFirst 2012, 1-20.

Gilmore, C.W. 1921. The fauna of the Arundel Formation of Maryland. Proceedings of the United States National Museum. 59: 581-594.

Kranz, P.M. Dinosaurs in Maryland. 1989. Published by Maryland Geological Survey, Department of Natural Resources, Educational Series No. 6.

Marsh, O.C. 1888. Notice of a New Genus of Sauropoda and Other New Dinosaurs from the Potomac Formation.

Please note that the usual disclaimer applies: views or opinions expressed here are mine, and do not reflect any institution with which I am affiliated.

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Filed under citizen science, Dinosaur Park, dinosaurs, field work, history of science, reviews, sauropods, systematics

Juan Bautista Bru and the First Fossil Mount

The first fossils ever assembled into a freestanding mount belonged to the giant ground sloth Megatherium. The fossils, which were unearthed near Luján in what is now Argentina, were described and mounted in 1795 by Juan Bautista Bru at the Royal Cabinet of Natural History in Madrid. But while the Megatherium mount played an important part in the history of paleontology and in our understanding of the changing Earth, the man who made it possible is scarcely mentioned in the literature. Instead, Bru’s work on Megatherium is typically overshadowed by the involvement of the much better known anatomist Georges Cuvier. Drawing principally from José López Piñero ‘s 1988 paper on Bru, this entry is intended to highlight and acknowledge Bru’s contribution to the practice of mounting fossils for public display.

Cuvier's adaptation of Bru's drawing.

Cuvier’s adaptation of Bru’s illustration of the Megatherium mount.

The Megatherium  in question was discovered  in 1789 in what was then the Viceroyalty of Rio de la Plata, on the banks of the Luján River, “a league and a half” from the town of the same name. As region was controlled by the Spanish monarchy at the time (although the Argentine War of Independence was not far off), it was standard procedure for viceroy Marqués de Lorento to ship the important find to Spain with all haste. Packed into seven crates, the nearly complete skeleton was delivered to the Royal Cabinet of Natural History in Madrid, which curated natural specimens from Spanish territories and was among the most respected scientific institutions in Europe.

By the late 1700s, the European Enlightenment was well established, and the pursuit of knowledge about the world through reason and scientific deduction rather than legend or dogma was popular among the societal elite. The study of natural history was deemed particularly important, and institutions like the Royal Cabinet which collected, quantified and published knowledge about the natural world were well-respected and well-funded. However, the meaning of the fossil record still eluded the top minds of the era. A century earlier, Nicolaus Steno had determined that fossils were the remains of once-living organisms, and by the late 1700s some naturalists were starting to come around to the idea that species that once existed had become extinct. Nevertheless, when the Megatherium arrived in Madrid, naturalists still lacked the most important part of the puzzle presented by the fossil record: an understanding of evolution and the interrelatedness of life on Earth.

The task of interpreting the Luján fossils went to Juan Bautista Bru, the “Artist and First Dissector” at the Royal Cabinet. Born in Valencia, Bru had initially tried his hand as a traditional artist, but found little success. After shifting his focus to natural science, Bru joined the Royal Cabinet in 1771 and remained there until his death in 1799. Bru primarily served as a scientific illustrator, combining his artistic skill with his extensive anatomical knowledge to produce gorgeously detailed drawings of biological specimens, as was required before photography became commonplace. He was also responsible for producing taxidermy pieces and occasionally, mounted skeletons of animals.  In 1777, Bru prepared and mounted the skeleton of an elephant that had died at the royal estate in Aranjuez, a task which doubtlessly provided useful practice for mounting the gigantic Megatherium.

Plate from Bru's monograph

Plate I from Bru’s Megatherium monograph.

Bru devoted four years to studying the Luján fossils, which were complete except for the animal’s tail. He completed his monograph in 1793, which included detailed descriptions of every skeletal element, in addition to 22 plates illustrating the bones from various angles. Among the illustrations was the completely articulated skeleton shown above, which is, incidentally, the first recorded instance of a skeletal drawing illustrating the living form of an extinct animal. Since the mounted skeleton did not go on display until 1795, it is unclear whether Bru based the illustration on the mount or vice versa. Unfortunately, little is known about how Bru created the Megatherium mount, and his drawing provides no information about the armature that supported the massive bones. Since Bru did not discuss the mount’s construction in his monograph, one can only surmise that the techniques he refined over the years building mounts of modern animal skeletons were applicable to the fossils. Wooden armatures were used to mount fossils in the early 1800s, and it is plausible that Bru pioneered this technique. Regardless of how it was supported, the  rhino-sized Megatherium mount was placed on a rectangular wooden platform in a room of the Royal Cabinet already devoted to fossils and minerals.

It is unclear why, but Bru never published his monograph, and this unfortunately resulted in him effectively being scooped by Georges Cuvier in 1796. A representative of the French government working in Santa Domingo acquired a set of proofs of Bru’s monograph and illustration, and passed them along to the Institut de France. The proofs made their way to Cuvier, who was well established as one of the world’s leading experts in anatomy and natural history. Although he had not yet seen the actual fossils, Cuvier wrote a brief article in the journal Magasin Encyclopedique on the South American creature, in which he coined the rather vague name Megatherium americanum, meaning American giant beast. Cuvier’s article was not without error (he claimed the fossils were found in Paraguay), but he did correctly recognize that the animal was an edentate* and was curiously similar to modern tree sloths**. In contrast, Bru’s description of the fossils, while thorough, contained no attempt at classification.

As it happened, Cuvier published a second important article on fossil animals in 1796: his Mémoires sur les espèces d’éléphants vivants et fossiles, in which he established that the mammoth fossils found in the Americas belonged to an extinct relative of modern elephants. The wave of attention Cuvier received that year for his contributions to the young field of paleontology apparently eclipsed any recognition of Bru’s multi-year study of the Megatherium. Bru ended up selling his monograph and illustrations to a publisher, and a translated version eventually appeared in a widely disseminated booklet with Cuvier’s Megatherium article in 1804, five years after Bru’s death.

Megatherium would continue to be important to 19th century paleontologists. Charles Darwin became interested in South American fossils during the second voyage of the HMS Beagle. In particular, the relationship between the extinct ground sloths and their modern relatives contributed to Darwin’s ideas about the succession of species over geologic time. In 1849, the British Museum produced a Megatherium mount of their own, a composite of two skeletons found very near to where the Spanish specimen was first discovered. Plaster casts of this mount would appear in museums on both sides of the Atlantic, and the original cast is still on display in London today (some of the fossils were destroyed during World War II). But while the discovery of Megatherium would be recounted often over the subsequent two centuries, it was Cuvier, not Bru, who was always given credit for introducing the animal to the world. Only in recent years has Bru’s name begun to circulate again in historical accounts.

The original Megatherium fossils have been remounted at the Museo Nacional de Ciencias Naturales. Image from TripAdvisor.

The original Megatherium fossils have been remounted at the Museo Nacional de Ciencias Naturales. Image from Virtual Tourist.

However, there is a bit of happiness at the end of this story. Unlike other early mounts like Peale’s mastodon and Hydrarchos, Bru’s Megatherium has survived to the present day. Remounted on a new steel armature in an approximation of the original quadrupedal pose, the Luján Megatherium fossils are on display at the Royal Cabinet’s spiritual successor, the National Museum of Natural Science in Madrid. On public display for a nearly uninterrupted 218 years, this specimen can  surely be said to have taken on a second life. It was once a giant beast that roamed across the ancient Argentinian plains, and now it is a monument to scientific achievement.

*Edentata is a historic paraphyletic group that includes sloths, anteaters, pangolins and aardvarks. Modern biologists recognize that the new world sloths and anteaters and old world pangolins and aardvarks are not closely related. The name Xenarthra is now used for sloths and their new world relatives.

**Cuvier was working many decades before Charles Darwin published On the Origin of Species, and as such, did not subscribe to the idea that species could change and diversify over time. It is therefore worth noting that while he recognized the similarity between Megatherium and modern sloths, he did not conceive of their relationship in an evolutionary sense (that is, related species sharing a common ancestor). 

References

Argot, C. (2008). Changing Views in Paleontology:
The Story of a Giant (Megatherium, Xenarthra). Mammalian Evolutionary Morphology. Pp 37-50.

López Piñero , J.M. (1988). Juan Bautista Bru (1740-1799) and the Description of the Genus Megatherium. Journal of the History of Biology. 21:1:147-163.

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Filed under fossil mounts, history of science, mammals, museums, paleoart

The Chimeric Missourium and Hydrarchos

In 1802, naturalist and painter John Peale unveiled the first mounted fossil skeleton ever put on display in the United States. The mount, a mastodon (Mammut americanum) collected on a farm near Newburgh, New York, immediately captured public attention and inspired a wave of interest in anything old and big. Although Peale charged admission to view the mastodon and somewhat dramatized its importance as “the first of American animals” and “the largest of terrestrial beings”, his primary intent was to educate the public about the natural world. Nevertheless, many American capitalists saw the crowds of people lining up to see Peale’s mastodon and concluded that there was a profit to be made in exhibiting fossils. The best known of these 19th century fossil showmen was surely Albert Koch. Having immigrated to the United States from Germany in 1835, Koch was a contemporary of P.T. Barnum, and like Barnum, he made a career out of exhibiting “curiosities”, some real and some fraudulent or exaggerated. At “Dr. Koch’s” (he never actually earned a doctorate) exhibition hall in St. Louis, Missouri, visitors paying the 50 cent admission fee could view wax sculptures, exotic animals, artifacts from distant countries, extensive miniature dioramas, and alleged freaks of nature. Koch also had a live grizzly bear and several alligators – sources differ on whether or not they were forced to fight for entertainment.

Missourium

In 1840, Koch received word of something much bigger. A Missouri farmer had discovered large fossil bones, and Koch quickly arranged to purchase the find along with the rights to search the farmer’s land for more. Within four months, Koch had assembled a complete mastodon skeleton. More than complete, actually: Koch’s mount included numerous extra vertebrae and ribs from one or more additional mastodon individuals. Like Peale before him, Koch placed blocks of wood between the vertebrae to further exaggerate the animal’s length. The result was a 32-foot mount, nearly twice as long as a typical mastodon. As a final flourish, Koch positioned the mastodon’s tusks pointing upwards, to make the beast look more fearsome. In order to differentiate his creation from Peale’s earlier exhibit, Koch called the creature “Missourium”, although there was no scientific reason to distinguish it from other mastodon finds. Missourium went on display at Koch’s St. Louis establishment later that same year, and proved to be an instant success. In fact, Koch decided that the composite mastodon mount was worth more than then every other display combined. In 1841, he sold the exhibit hall and took Missourium on tour, traveling to New Orleans, Philadelphia, and several other American cities.

Illustration of Missourium. Out-of-copyright image via Laelaps.

Contemporary academics, including the British naturalist Richard Owen, pointed out that Koch’s mount was clearly an incorrectly assembled composite, and expressed disapproval for Koch’s sensationalized treatment of important fossil specimens. Just like famous P.T. Barnum frauds like Joice Heth and the Feejee mermaid, however, the controversy surrounding Missourium’s legitimacy only increased the enthusiasm of the paying public.  As an interesting side note, Koch claimed to have found stone tools and other human artifacts alongside the Missourium fossils. He included a pamphlet with his traveling exhibit which explained that these tools demonstrated that human populations in North America extended much further back in time than had been previously assumed. Koch may well have been telling the truth about where he found the artifacts and would eventually turn out to be correct about the antiquity of American humans. Nevertheless, because of the obviously fraudulent nature of Missourium, scientists of the day saw fit to ignore Koke’s suggestions entirely.

Hydrarchos

Koch sold Missourium to the British Museum in 1843, but he was soon at it again in 1845, when he began scouring Alabama for new display-worthy fossils. This time, Koch was after the bones of the prehistoric whale Basilosaurus cetoides. The Philadelphia-based naturalist and physician Richard Harlan had first described and named Basilosaurus in 1835 (he erroneously thought it was a reptile, hence the name meaning “king lizard”), but its fossils had been well known in the American south for decades before that. Enslaved men and women often ran into the bones while plowing fields, and these fossils were sometimes used as furniture or foundation posts for houses. Between January and April of 1845, Koch traveled across Clarke, Choctaw, and Washington counties, retrieving Basilosaurus remains. His best find was an articulated partial skeleton, including much of the skull, which he unearthed near the Tombigbee River.

After accumulating parts of at least six Basilosaurus individuals, Koch combined the fossils into a 114-foot mount (he would claim that it was 140 feet). Just as he had with Missourium, Koch strung together the vertebrae of multiple animals, extending his creation’s length to an absurd degree. This time, Koch did not even limit himself to whale fossils: as naturalist Jeffries Wyman would point out, many of the elements in Koch’s chimeric creation were actually ammonite shells. Billed as a sea serpent called “Hydrargos sillimani” (named after Yale professor Benjamin Silliman, who was not involved in the project and immediately requested that the reference be removed), the mount was first exhibited at the Apollo Saloon in New York City. Hydrargos, eventually renamed Hyrarchos, proved to be even more popular and profitable than Missourium. Cleverly, Koch had constructed the skeleton not as a single structure but as several modular components secured to wooden boards. This made it easy for the showman to disassemble, transport, and reassemble the display, which he toured throughout the United States and Europe.

Illustration of Hydrarchos in New York.

Illustration of Hydrarchos in New York’s Apollo Saloon.

As they had with Missourium, scientists confronted Koch over his inaccurate and sensationalized displays. Undaunted, Koch eventually sold the Hydrarchos mount to the Prussian King Friedrich Wilhelm IV, who exhibited it in Berlin’s Royal Anatomical Museum despite the insistence by the museum’s experts that the mount was a fraudulent reconstruction. Koch was still not finished, however. In 1848 he completed a second Basilosaurus composite, this one 96 feet long, and again took it on tour. The Mark II Hydrarchos would eventually be sold to Colonel Wood’s Museum in Chicago. E.L. Wood’s “museum” was yet another exhibition of mostly-bogus oddities, like Koch’s original operation in St. Louis. Still, the Basilosaurus mount’s final home can be credited for correctly identifying it as a prehistoric whale. The composite mount was labeled as “Zeuglodon”, a junior synonym coined by Richard Owen when he determined that the Alabama fossils belonged to marine mammals, not reptiles. Properly identified or not, the mount was destroyed along with the rest of Wood’s Museum during the great Chicago fire in 1871. Most of the original Hydrarchos was lost during World War II, although some parts remain at the Humboldt Museum in Berlin.

Modern Influences

Koch’s fossil mounts were frustrating to 19th century paleontologists because they cast unnecessary doubt on their young discipline. The actual bones that made up Missourium and Hydrarchos were genuine, Koch had merely assembled them incorrectly to enhance the appeal and profitability of his displays. To the scientists’ chagrin, when they criticized Koch’s displays, the popular press and the public often misinterpreted their statements and became skeptical of fossil finds in general. During the 19th century, ideas like extinction and the great age of the Earth were very new, and Koch’s spurious commodification of hard evidence made it harder for legitimate researchers to be taken seriously in the public sphere.

In fact, modern paleontologists still have to do damage control when the occasional forgery turns up. In 1999, the discovery of “Archaeoraptor” was widely publicized in National Geographic magazine and elsewhere as a feathered dinosaur that provided important evidence for the dinosaurian origin of birds. Archaeoraptor was not the first feathered dinosaur ever found, but it was one of the early ones, back when the concept of dinosaurs with feathers was still news. Unfortunately, it was only after the National Geographic article had gone to press that paleontologists Xu Xing and Phil Curie determined that the Archaeoraptor specimen, which had been smuggled into the United States from China by an unknown dealer, was actually a composite. Someone in China knew that a complete skeleton was worth more than an incomplete one, and cemented together partial skeletons of several dinosaurs, including Microraptor and Yanornis. When National Geographic retracted the story, however, many readers misunderstood the extent of the forgery. They thought that the feathers, the most exciting part of the find, had been faked, when in reality all the parts of Archaeoraptor were quite real, they just belonged to different animals.

This out-of-copyright image of Hydrarchos provides a good look at the mount's wooden armature. Out-of-copyright image via Laelaps.

This image of Hydrarchos provides a good look at the mount’s wooden armature. Incidentally, the above caption is accurate. Out-of-copyright image via Laelaps.

More than ten years later, writers with creationist agendas and a few scientists who ought to know better are still pushing the myth that Archaeoraptor was a deliberate hoax. Literally hundreds of genuine feathered dinosaur specimens found since then contribute to the scientific consensus that birds area incontrovertibly dinosaurs. And yet, paleontologists are still fighting skepticism inspired by the Archaeoraptor mistake.

19th century paleontologists paid for Koch’s displays in much the same way. Editorials denouncing evolution and the fossil record repeatedly referenced Koch’s ridiculous chimeras, as though these showpieces were representative of paleontologists’ work. I suspect that the general animosity paleontologists of the era felt toward fossil mounts came from dealing with Koch’s legacy. O.C. Marsh, for instance, hated the idea of mounting fossils and refused to let any of his finds be displayed in such a way during his lifetime. It would not be until 1868 and the discovery of the first somewhat complete dinosaur remains that paleontologists would again see mounting as a legitimate means for displaying their finds.

References

Carpenter, K., Madsen, J.H. and Lewis, L. (1994). Mounting of Fossi Vertebrate Skeletons. In Vertebrate Paleontological Techniques, Vol. 1. Cambridge, UK: Cambridge University Press.

Jones, D.E. 1998. Doctor Koch and his “Immense Antidiluvian Monsters.” http://www.alabamaheritage.com/vault/monsters.htm

Rogers, M. 2010. Delia’s Tears: Race, Science and Photography in Nineteenth Century America. New Haven, CT: Yale University Press.

Simpson, G.G. 1942. The Beginnings of Vertebrate Paleontology in North America. Proceedings of the American Philosophical Society. 86:1:130-188.

Switek, B. 2008. “Koch’s “Mammoth” and Human Antiquity.” http://scienceblogs.com/laelaps/2008/06/18/too-little-too-soon/

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Filed under fossil mounts, history of science, mammals, museums

The Artist in His Museum: Peale’s Mastodon

In 1801, naturalist and painter Charles Wilson Peale assembled in Philadelphia the skeleton of a mastodon (Mammut americanum).While Peale’s mastodon was not the first fully assembled fossil animal put on display, it was assuredly the first display of this type to capture widespread public attention, particularly in the United States. What’s more, the mastodon became an important symbol for the untold natural wonders of the American continent, which was still largely unexplored (by European colonists) at the beginning of the 19th century. Finally, Peale’s mastodon made clear to the public one of the most important principles of modern biology: the idea that organisms can become extinct.

The Peale Museum mastodon, as illustrated by Charles Peale's son, Rembrandt. The Peale Museum mastodon, as illustrated by Charles Peale’s son, Rembrandt.

An extinct giant

The story of the mastodon mount actually began a full century before the 1806 debut. In 1705, a farmer in Claverack, New York found an enormous tooth that had eroded out of a hillside. The farmer traded the tooth to a local politician, and it eventually made it its way into the hands of New York’s colonial governor, Edward Hyde, 3rd Earl of Clarendon. Hyde in turn sent the tooth to London, describing it as a remnant of an antediluvian giant. As word of the remains of a giant spread, other Americans soon began reporting similar finds. Throughout the colonies, giant bones, teeth, and tusks began to be uncovered. While early reports called these fossils the remains of “incognitum,” or “the unknown,” naturalists caught on reasonably quickly that these were not the bones of giant men but of elephant-like creatures.

At this point a brief digression on etymology and taxonomy is required. For most of the 19th century, the American fossil elephants were invariably called “mahmot” or “mammoth.” This was an Anglicization of the Old Vogul term maimanto (meaning earth-horn), which referred to giant tusks occasionally found in Siberia. It is unclear, however, who first made the correct connection between the frozen mammoths of Siberia and the American fossil skeletons. Credit for adopting “mammoth” as a synonym for “big” goes to Thomas Jefferson, who was fascinated by paleontology and the mammoth fossils in particular.

It was not until 1817 that French anatomist Georges Cuvier recognized that there were at least two types of extinct American proboscideans: the taller mammoths and stockier mastodons. Unequivocally demonstrating the staggering repression of the Victorian era, Cuvier coined the name “mastodon,” meaning nipple tooth, because apparently he thought the animal’s most distinguishing feature was that its teeth looked like breasts.

Boobs? Couvier, you poor bastard. Cuvier, you poor bastard.

The American elephantine fossils raised difficult questions for naturalists. The fossils clearly belonged to animals that had never been seen alive, which meant that the entire species must have died out. This concept of extinction was new to science, and it challenged the biblically-inspired presumption that all species had originated in a single creation event. Cuvier was a leader in the 19th century scientific movement known as catastrophism–the idea that extinctions were the result of periodic disasters, such as floods. While Cuvier himself rejected the idea that populations of organisms could avoid extinction by adapting and changing, his work on extinction would prove important when Charles Darwin worked out the process of evolution several decades later.

Unearthing the mastodon

In 1789, Nicholas Collin of the American Philosophical Society proposed a search for a complete mammoth skeleton, in order to resolve the animal’s identity and the question of its extinction once and for all. Collin’s call was answered by Charles Wilson Peale, founder of America’s first modern museum. Peale is best known today as a portrait artist during the American Revolution, but he was also the founder of the Peale Museum in Philadelphia. Although semi-formal collections of interesting natural specimens had existed before, Peale uniquely fashioned his institution as a space for public education, rather than a private vanity project. On the second floor of Philadelphia’s Independence Hall, Peale arranged displays of mammals, birds, and plants in a scala naturae, which was the contemporary understanding of natural order. Peale intended the museum to be a public resource that would improve visitors’ moral character through lessons in science, as was made clear by the slogan printed on every ticket, “the birds and beasts will teach thee.”

In 1799, a farmer named John Masten reported that he had found bones of “an animal of uncommon magnitude” on his land outside Newburgh, New York. Masten gathered a large party of friends and neighbors to help excavate the find. This proved to be a little too much fun: the crowd eventually descended into alcohol-fueled chaos, and many of the fossils were destroyed. Nevertheless, Peale decided to pay Masten a visit, with the hope of securing mammoth fossils for his museum. Peale ended up paying Masten $200 for the surviving fossils, plus another $100 for the right to search his land for more remains. Peale returned to Masten’s farm with a better-organized crew and $500 in additional funding from the American Philosophical Society. The ensuing excavation is the subject of Peale’s 1806 painting, The Exhumation of the Mastodon, shown below.

“The Exhumation of the Mastodon” by Charles Peale, 1806.

Although highly dramatized, The Exhumation of the Mastodon provides the best available record of the event. Since the pit where Masten first found the bones had filled with water, Peale oversaw the construction of a huge wooden wheel, which drove a conveyor belt hauling buckets of water out of the work site. Peale himself can be seen on the right, presiding over his small army of excavators. The well-publicized project eventually uncovered most of a mastodon. Exploring a few nearby farms, Peale’s workers eventually accumulated enough material to build a complete skeleton, most notably a mandible found on another farm down the road. In what was either showmanship or genuine confusion regarding the diets of elephants, Peale said of the find, “Gracious God, what a jaw! How many animals must have been crushed beneath it!” (quoted in Simpson 1942, 159).

The mastodon on exhibit

Once the mastodon skeleton had been transported to Philadelphia, the process of building the mount fell upon Peale’s son Rembrandt and Moses Williams, a free man of color who worked for the Peales. It took three months to articulate the skeleton, although sadly the details of how it was mounted on its armature are lost to history. Initiating a practice that would become necessity for most fossil mounts in years to come, Rembrant filled in missing parts of the mastodon skeleton (the top of the cranium and the tail) with sculpted elements. In addition, wooden discs were placed between vertebrae, slightly exaggerating the mount’s total length.

The completed mastodon mount was unveiled in 1802, in the main hall of the American Philosophical Society. Shortly thereafter, it was moved to the Peale Museum at Independence Hall. For 50 cents (plus regular admission), the visiting public could marvel at the creature Peale touted as “the first of American animals” and “the largest of terrestrial beings.” The mastodon (still being called a mammoth at that time) was a sensation, stirring up fascination with natural science, the prehistoric past, and no small amount of ours-is-bigger-than-yours patriotism in the young United States. In 1822, Peale would commemorate the unveiling of the mastodon with his self portrait, The Artist in His Museum. Ever the showman, Peale ensured that the skeleton in his painting is only barely visible below the rising curtain.

“The Artist in His Museum” by Charles Peale, 1822.

After Peale’s death in 1827 his museum floundered, and was eventually reduced from a meritorious educational institution into a circus of cheap spectacle. It shut down for good in 1848, and the mastodon (by then one of many similar mounts) was put up for auction. There are several conflicting accounts of what became of the mount, including the suggestion that it was destroyed in a fire, but in fact Peale’s mastodon has survived to the present day. Johann Jakob Kaup purchased the skeleton for the Landesmuseum in Durmstadt, Germany, and it has remained on display there ever since.

Germany Peale’s mastodon survives in Durmstadt, Germany. Source

Peale’s mastodon left an unmistakable legacy for both paleontology and public education. Today, the public conception of prehistory is inseparably connected to the image of towering mounted skeletons in museum halls. But fossils do not come out of the ground bolted to steel armatures, so it is largely thanks to Peale that mounts have become the most enduring means of sharing paleontology with the public.

References

Carpenter, K., Madsen, J.H. and Lewis, L. (1994). Mounting of Fossil Vertebrate Skeletons. Vertebrate Paleontological Techniques, Vol. 1. Cambridge, UK: Cambridge University Press.

Connriff, R. (2010). Mammoths and Mastodons: All American Monsters. Smithsonian Magazine. http://www.smithsonianmag.com/science-nature/Mammoths-and-Mastodons-All-American-Monsters.html

Semonin, P. (2000). American Monster: How the Nation’s First Prehistoric Creature Became a Symbol of National Identity. New York, NY: New York University Press.

Simpson, G.G. (1942). The Beginnings of Vertebrate Paleontology in North Ameirca. Proceedings of the American Philosophical Society 86:130-188.

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Filed under field work, fossil mounts, history of science, mammals, museums

The NMNH fossil halls, circa 1963

c.02

A revamp for the dinosaur displays in Hall 2. Courtesy of the Smithsonian Institution Archives.

Since the NMNH building opened in 1910 as the United States National Museum, the east wing has been home to fossil displays. Although there have been many small adjustments and additions to the exhibits over the years, we can separate the east wing’s layout into three main periods. From 1910 t0 1945, the exhibits were primarily under the stewardship of Charles Gilmore. Called the “Hall of Extinct Monsters”, this iteration was somewhat haphazard in its layout and generally resembled a classic “cabinet of curiosity” approach to exhibit design. Gilmore’s version of the east wing remained in place until 1963, when the space was redesigned as part of the Smithsonian-wide modernization project. In the updated halls, there was a directed effort to compartmentalize exhibits based on the subdivisions of the Museum’s research staff, with each area of the gallery becoming the responsibility of a different curator. A second renovation was carried out in several stages starting in 1980. This version, which was open until 2014, was part of the new museology wave that started in the late 1970s. As such, the exhibits form a more cohesive narrative of the history of life on earth, and much of the signage carries the voice of educators, rather than curators.

Of course, the field of paleontology has advanced by leaps and bounds since the early 1980s, and NMNH staff have made piecemeal updates to the galleries when possible, including restorations of deteriorating mounts, and additional signage that addresses the dinosaurian origin of birds and the importance of the fossil record for understanding climate change. A third renovation is currently underway and will be completed in 2019.

But I’m getting ahead of myself. The purpose of this post is to provide an overview of the NMNH fossil halls as they stood in 1963, after the first major renovation. This iteration of the east wing was long gone before I was born, so this information is pieced together from historic photographs, archived exhibit scripts, and correspondence among the individuals involved in the modernization project (my thanks to the staff of the Smithsonian Institution Archives for their assistance in accessing these materials). Perhaps unsurprisingly, records of the dinosaur gallery are by far the most thorough. Information on the other halls is considerably harder to come by, so if any readers who saw the older exhibits in person remember any details, it would be fantastic if you could share them.

Layout of the USNM east wing, circa 1963.

Layout of the USNM east wing, circa 1963.

As mentioned, the Smithsonian underwent a thorough modernization project in the middle of the 20th century. The modernization committee, chaired by Frank Taylor (the eventual director-general of Smithsonian museums), was established in 1948. Under the committee’s guidance, most of the institution’s exhibits were redesigned between 1953 and 1963. Keep in mind that at the time, the United States National Museum was the only Smithsonian museum – it would not be divided into the National Museum of Natural History and the National Museum of History and Technology (now the National Museum of American History) until 1964.

Completed in 1963, the USNM fossil exhibits were among the last to be modernized. Only a small number of specimens were added that had not already been on view in the previous version of the space – in fact, many specimens were removed. The changes primarily focused on the layout of the exhibit, turning what was a loosely organized set of displays into a series of themed galleries. The east wing included four halls in 1963, the layout of which can be seen in the map above. Each hall was the responsibility of a particular curator. Nicholas Hotton oversaw Paleozoic and Mesozoic reptiles in Hall 2. David Dunkle was in charge of fossil fish in Hall 3. Porter Kier oversaw fossil invertebrates and plants in Hall 4. Finally, Charles Gazin, head curator of the Paleontology Division, was responsible for Cenozoic mammals in Hall 5. Each curator had a central role in selecting specimens for display and writing accompanying label copy.

Invertebrates and Fossil Plants

echinoderms1961

Echinoderm fossil display in Hall 4. Courtesy of the Smithsonian Institution Archives.

It is likely that part of the reason the fossil halls were late on the modernization schedule was that the curators of the Paleontology Division were not terribly interested in exhibits or outreach. There were no staff members in the division exclusively devoted to exhibit work, so the task of designing the new exhibit space was an added burden for the research staff. As invertebrate paleontology curator G. Arthur Cooper put it in a 1950 memo, “all divisions of Geology at present are in an apathetic state toward exhibition.”

Nevertheless, work on the east wing halls had begun by 1957, if not a bit earlier. The first of the new exhibits to be worked on was Hall 4, featuring fossil invertebrates and plants. The long and narrow space was divided into four sections: the first introduced the study of fossils and how they are preserved, the second was devoted to paleobotany, the third contained terrestrial and marine invertebrates, and the forth provided an overview of geological time. Cooper described the new exhibit as a progressive story of the expansion of life, “its stem connecting all life which is now culminating in man.”

Carboniferous coal swamp fossils in Hall 4. Photo courtesy of the Smithsonian Institution Archives.

In addition to a variety of fossil specimens, Hall 4 featured a series of dioramas built by George Merchand, an exhibit specialist from Ann Arbor, Michigan. Merchand built at least 4 dioramas between 1957 and 1958, each depicting representative invertebrate marine fauna from a different Paleozoic period. Most, if not all, of these dioramas were retained during the 1980s renovation and remained on view through 2014.

Fossil Fishes and Amphibians

Fossil fishes in Hall 3. Photo courtesy of the Smithsonian Institution Archives.

Fossil fish and a smattering of amphibians were located in Hall 3, on the far east side of the wing. This space would be converted into “Mammals in the Limelight” in the 1980s. David Dunkle, for whom everyone’s favorite placoderm Dunkleosteus is named, was in charge of this gallery during his tenure at USNM between 1946 and 1968. The specimens on view were arranged temporally, starting with placoderms on the south side and progressing into actinopterygians and basal amphibians on the north end. Among the more prominently displayed specimens were Xiphactinus, Seymouria, and “Buettneria” (=Koskinonodon). The hall also contained a replica of the recently discovered modern coelacanth, and small diorama of a Carboniferous coal swamp.

Dinosaurs and Other Reptiles

Dinosaurs in Hall 2, as seen facing west. Photo courtesy of the Smithsonian Institution Archives.

Hall 2, featuring dinosaurs and other reptiles, was the main draw for most visitors. It was not, however, a major priority for the Smithsonian research staff. The museum had not had a dinosaur specialist since Gilmore passed away in 1945 and indeed, dinosaurs were not an especially popular area of study among mid-century paleontologists in general. As such, responsibility for Hall 2 fell to Nicholas Hotton, at the time a brand-new Associate Curator. Later in his career, Hotton would be best known as an opponent to the dinosaur endothermy movement, but in the early 1960s he was most interested in early amniotes and the origin of mammals.

Hotton’s display of South African synapsids and amphibians. Photo courtesy of the Smithsonian Institution Archives.

Perhaps due to the general disinterest among USNM curators, changes to the dinosaur exhibits were mostly organizational. Most of the free-standing dinosaur mounts built by Gilmore and his team were collected on a single central pedestal. Preferring not to tackle the massive undertaking of disassembling and remounting the 70-foot Diplodocus skeleton, the exhibit designers left the sauropod in place and clustered the smaller moutns around it. In the new arrangement, the Diplodocus was flanked by the two Camptosaurus and prone Camarasaurus on its right and by Triceratops and Brachyceratops on its left. The Stegosaurus stenops holotype, splayed on its side in a recreation of how it was first discovered, was placed behind the sauropods at the back of the platform.

Close up of Thescelosaurus on the south wall. Photo courtesy of the Smithsonian Institution Archives.

 The north and south walls of Hall 2 were lined with additional specimens. On the south side, Gilmore’s relief mounts of Ceratosaurus and Edmontosaurus (called “Anatosaurus” in this exhibit) were joined by the gallery’s one new dinosaur, a relief mount of Gorgosaurus in a death pose. The north wall featured a long, narrow, glass-enclosed case illustrating the basics of dinosaur classification. In addition to saurischian and ornithischian pelves, the case featured skulls representing most of the major dinosaur groups. Amusingly, all but two of these skulls (Triceratops and Diplodocus) were labeled with names that are no longer considered valid. These skulls included “Antrodemus” (Allosaurus), “Trachodon” (Edmontosaurus) “Procheneosaurus” (probably Corythosaurus)  and “Monoclonius” (Centrosaurus).

In the southwest corner of Hall 2 (where FossiLab is today), visitors could see the Museum’s two free-standing Stegosaurus: the fossil mount constructed by Gilmore in 1913 and the charmingly ugly papier mache version, which had received a fresh coat of paint. Finally, the rear (east) wall of Hall 2 held Gilmore’s relief mounted Tylosaurus.

Mammals

c.11

Brontotherium and Matternes’ Oligocene mural in Hall 5. Photo courtesy of the Smithsonian Institution Archives.

Fossil mammals were exhibited in Hall 5, a corridor-like space accessible from the main rotunda and via two doorways on the north side of Hall 2. After 1990, this space would house the “Life in the Ancient Seas” exhibit. Charles Gazin, head curator of the Division of Paleontology, was in charge of this space on paper, but my impression is that his attention was elsewhere during its design and construction. Gazin was apparently approached by the modernization committee several times during the 1950s, but was reluctant to commit his time to a major renovation project. Gazin had been spending a great deal of time at a Pliocene dig site in Panama, and the collection of new fossils proved more interesting than designing displays. As Gazin tersely explained, “It is a little difficult to concentrate objectively on exhibition problems here in the interior of Panama.”

Basilosaurus and Cenozoic reptiles in Hall 5. Photo courtesy of the Smithsonian Institution Archives.

Nevertheless, Gazin’s interest in Cenozoic mammals ensured that his gallery was exceptionally thorough. Thanks to Gazin’s own collecting expeditions throughout the 1950s, the new fossil mammals galleries contained representatives of nearly all major mammal groups, from every epoch from the Paleocene through the Pliocene (the Pleistocene was deliberately excluded, as a separate ice age exhibit was also in the works). Classic mounts from the Gilmore era like Basilosaurus and Teleoceras were joined by dozens of less showy specimens like rodents, small perissodactyls, and early primates. The new exhibit also introduced the first wave of Jay Matternes’ much-beloved murals, illustrating the changing flora and fauna in North America over the course of the Cenozoic.

Unveiling and Reactions

The new east wing galleries officially opened on June 25, 1963. According to the press release, “the new exhibit features in colorful and dramatic settings more than 24 skeletons and skulls of the largest land animals the world has ever known.” The exhibits were officially unveiled with a late afternoon ceremony, in which Carol Hotton (Nicholas Hotton’s daughter) cut the ribbon and the lights to Hall 2 were suddenly turned on to dramatic effect.

Unfortunately, the new exhibits were not universally loved by the museum staff. The wing had been planned a set of compartmentalized exhibits, each corresponding to a subdivision of the Division of Paleontology, with a different curator taking responsibility for each hall. While seeming sensible on paper, this plan turned out to be a logistical nightmare, and a common cause for complaint among Division staff for the next decade. In addition, Gazin in particular voiced concerns as early as January 1964 that the design of the new halls was entirely inadequate for preventing accidental or deliberate damage to specimens by visitors. The mounts in Hall 2 were raised only about a foot off the ground, and were not protected by any sort of guard rail or barrier. As a result, within a few months of the exhibit’s unveiling, several ribs and vertebral processes had been broken off or stolen from CamarasaurusGorgosaurus, Ceratosaurus and others.

With the notable caveat that I never saw the 1963 exhibits in person, I would say that this is aesthetically my least favorite iteration of the east wing. The grandiose, institutional Greco-Roman architecture originally displayed in the Hall of Extinct Monsters was replaced with what can only be described as extremely 1960s design. Solid earth-tone colors, wood paneling and wall-to-wall carpeting gave the halls a much more austere character. While the efforts to categorize specimens into thematic zones was commendable for a museum of that era, the label copy (written by the curators) was still highly pedantic and verbose. As such, the 1963 fossil halls seem to have been very much of their time. While the designers were working to avoid the overt religiosity and grandeur of turn of the century museums, they had not yet reached the point of developing truly audience-centered educational experiences. The result was an exhibit that was humble, yet still largely inacessible. Perhaps for this reason, the 1963 fossil halls were the shortest-lived at NMNH to date, being replaced within 20 years of their debut.

This post was updated and edited on January 8, 2018.

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Filed under dinosaurs, exhibits, Extinct Monsters, fish, fossil mounts, history of science, mammals, museums, NMNH, reptiles, science communication

A Triceratops for Lawrence

In an earlier post, I described how the Smithsonian’s Triceratops was the first free-standing mount of this animal ever created, and the eccentricities of its proportions and posture would define how the species would be depicted in artwork and other reconstructions for the better part of a century. I should have clarified, however, that this was not the first time Triceratops fossils were put on public exhibit. That honor goes to the University of Kansas Natural History Museum, which was founded in 1864 and is still operational today.

Among the Museum’s basement paleontology exhibits is a case of dinosaur fossils that has literally gone unchanged since the 1950s. Although this time capsule of mid-century museum design is of some historical interest, it would be nice if those sauropod limb bones weren’t labeled “Brontosaurus” (to be clear, the whole museum doesn’t look like this, the staff has been slowly but surely modernizing the exhibits). Of particular importance is the Triceratops skull (specimen 422) on the left side of the case. While there is no historical information on its label, this specimen has been with the museum for over 115 years, having been unearthed and put on display only six years after O.C. Marsh first named and described Triceratops.

The dinosaur case at the KU Natural History Museum, untouched since the 1950s.

The dinosaur case at the KU Natural History Museum, untouched since the 1950s.

The story of the KU Triceratops is not well-known, although it is the subject of the somewhat hard-to-find book (neither the Museum nor the KU library has a copy) A Triceratops Hunt in Pioneer Wyoming. In the summer of 1895, a team from the University ventured into the frontier lands of of eastern Wyoming with the explicit goal of finding a Triceratops for display at the young Natural History Museum. The team was led by Samuel Wendell Williston, founder of the University’s geology department. Although Williston’s specialty was entomology, he had previously worked under Marsh at Yale and was well-acquainted with the plethora of dinosaurs on which his mentor had published. Also on the expedition were KU Regent James Polk Sams, and two individuals whose names are quite familiar to anyone with an interest in the history of paleontology, Barnum Brown and Elmer Riggs. Brown would, of course, go on to be the star fossil hunter at the American Museum of Natural History, while Riggs would become a curator at the Field Museum of Natural History. In 1895, however, both were students, and not especially interested in fossil collecting or paleontology. 

The team found the Triceratops they were looking for on July 9, near the confluence of Lightning and Lance Creeks. By July 22, the skull was fully excavated and crated for a journey by train back to Lawrence. The fossil apparently garnered a fair amount of attention on the journey; while Triceratops is well known today, in 1895 few had any idea that animals such as this had ever walked the Earth. And yet, here was clear, physical evidence of an extinct animal like nothing alive in the modern world, and it would soon be displayed for all to see in the University of Kansas Museum.

Triceratops skull retrieved by the 1895 Wyoming expedition.

Triceratops skull retrieved by the 1895 Wyoming expedition.

The 1895 expedition was not tremendously productive scientifically, the fossils found that summer resulting in only three short papers. However, the journey, and the Triceratops skull that was brought back, did end up being quite important for paleontology. The expedition inspired Brown and Riggs to pursue careers in paleontology, and as Brinkman and colleagues write in Triceratops Hunt in Pioneer Wyoming, “they would hunt bones for the rest of their lives, to the great benefit of science, and might never have done so had not circumstances landed them in the circle of Williston’s influence in the summer of 1895.”

Furthermore, by setting out with the clear goal to find a dinosaur for display, the University of Kansas team were trailblazers in a movement that would lead to the inseparable connection between dinosaurs and museums in popular culture today. In the first decade of the 20th century, newly burgeoning large urban museums openly competed to find and display the largest and most spectacular dinosaurs. Exhibits like the AMNH Brontosaurus, the Carnegie Museum of Natural History Diplodocus and, of course, the Smithsonian Triceratops brought millions of Americans into museums, ensuring that to this day, when we think of museums, we think of dinosaur skeletons (and vice versa). In spite of the somewhat dingy basement display it currently finds itself in, the University of Kansas Triceratops was an early trendsetter and a profound example of the intersection of science and history.

Reference

Kohl, M.F., Martin, L.D. and Brinkman, P., eds. (2004). Triceratops Hunt in Pioneer Wyoming: The Journals of Barnum Brown and J.P. Sams. Glendoo, WY: High Plains Press.

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Filed under dinosaurs, field work, fossil mounts, history of science, marginocephalians, museums, reptiles

Allan McCollum’s fossil art

Click here if the embedded video doesn’t work.

My first love is natural science, but I also fancy myself an amateur art enthusiast, particularly for performance and installation pieces from the last 50 years or so. I am fascinated by art that directly engages the viewer, art that is not complete without the involvement of the spectator. As it happens, mounted fossil skeletons are a great example of  installation art, although they are not deliberately constructed as such. The size and presence of a dinosaur skeleton, such as the Stegosaurus below, necessarily incorporates the viewers’ human scale into the experience. Viewers are not merely spectators but participants in a shared performance. Nevertheless, fossils are nearly always displayed and interpreted as scientific specimens, rather than art objects.

Stegosaurus fossil mount and life-size model circa 1913. Photo courtesy of the Smithsonian Institution Archives.

Stegosaurus fossil mount and life-size model at USNM circa 1913. Photo courtesy of the Smithsonian Institution Archives.

One important exception occurs in the work of prolific New York-based artist Allan McCollum. McCollum’s installations frequently address repetitive labor and industrial manufacturing, often incorporating hundreds or thousands of similar but subtly unique objects. Each piece is the product of many small actions, gradually assembled over time. In the early 1990s, the artist turned his attention to fossils, particularly their historic meaning and aesthetic appeal.

"Lost Objects" by Allan McCollum. Image from Art21.

“Lost Objects” by Allan McCollum. Image from Art21.

In 1991, McCollum collaborated with the Carnegie Museum of Natural History to produce “Lost Objects”, displayed next door at the Carnegie Museum of Art. Using molds taken from dinosaur fossils (apparently all limb bones) in the CMNH collection, the artist produced several hundred fossil casts for the installation shown above. To me, this piece is a reflection on the global sharing of fossil material permitted by casting technology. In the Art21 video at the top of this post, McCollum briefly discusses the prominence of casts among the dinosaur mounts that are a staple at natural history museums. Dinosaur skeletons are virtually never found complete, and mounts are often filled in with casts of specimens held by other museums. For example, the National Museum of Natural History Diplodocus mount incorporates casts of the left hindlimb and much of the neck of the Carnegie Diplodocus. What’s more, casted duplicates of the entire Carnegie Diplodocus can be seen in London, Berlin and several other cities in Europe and Latin America, and casts of the American Museum of Natural History Tyrannosaurus are on display in Denver and  Philadelphia. It would be an impressive sight if all the casts of certain fossil specimens scattered around the world were reunited in one room, a monument to the knowledge gained from a century of scholarly collaboration. It would also commemorate the intangible excitement generated by dinosaur mounts, made possible only through the duplication and sharing of casts.

MCollum also comments that “there aren’t as many dinosaur bones in the world as we think.” Perhaps, then, “Lost Objects” is a reflection on the scarcity of intact fossils, by showing an impossibly large collection that no museum could hope to amass. Let’s just hope he wasn’t trying to comment on the alleged mass-production of casts cheapening the original fossils and the museums that hold them, because he’d be dead wrong (EDIT: He wasn’t, see comments).

mccollumnaturalcopies

“Natural Copies” by Allan McCollum. Image from Art21.

In 1995, McCollum followed up on “Lost Objects” with “Natural Copies, a series of casted dinosaur footprints produced in collaboration with the College of Eastern Utah Prehistoric Museum. For the artist, this piece was a reflection on the idea that 150 million-year-old fossils can be valued as cultural history. The footprints in question were found by the hundreds in a Utah coal mine. While many ended up at the museum, others were collected by miners to display at home. The fossils took on a second life as symbols the community’s workforce and natural heritage, irrelevant to the dinosaurs that produced the tracks but important all the same. McCollum’s work separates the fossils from their typical scientific context so that viewers may reflect on their cultural meaning and even the aesthetic beauty of their form.

So what’s the point of these installations? These appropriations of fossils as aesthetic pieces has no bearing on the science of paleontology, and in fact may obscure information about how the animals that left these traces lived and behaved. And yet, from the moment a fossil is first seen by human eyes, whether it is an ammonite preserved in a split open rock or the glint of a vertebrate bone weathering out of a hillside, it becomes meaningful on a human scale. For the discoverer, the researcher who describes the fossil, the institution that holds it in its collection and the visitor who sees the fossil on display, that specimen has cultural value. This does not diminish the value of fossils as natural specimens, but rather enhances their importance.

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Filed under collections, dinosaurs, fossil mounts, museums, paleoart

Beating the orthogenetic horse

According to the rad personalized 2012 review provided by WordPress, the top search engine terms leading people here over the last year were dinosours, horse evolutionary tree, horse evolution tree, horse phylogenetic tree and Daspletosaurus. It’s not too difficult to pick out the pattern there – horse evolution seems to be a major draw, even though I only mentioned it in a single post back in June. I aim to please, so I suppose a more detailed discussion of horse phylogeny is in order. First off, let me recommend Brian Switek’s thorough and thoughtful take on the subject. If you stick around here, you’re going to get more of a tirade.

Most depictions of horse evolution available online, including the one I posted a few months ago that is luring people to this site, are terrible. The typical linear presentation of horses progressively increasing in size from Eohippus to modern Equus, losing toes along the way, misrepresents not only what we know about horses as a group, but how evolution works in general.

This didn’t happen.

Evolution is, of course, neither linear nor progressive: it is primarily the result of populations adapting to thrive in their particular environments. As environments change over time species may evolve or go extinct, but there is no predetermined goal that lineages are reaching for. Modern Equus is not the most “highly evolved” horse – this is, in fact, a misleading if not meaningless concept, because a species’ success is dependent on its ability to thrive in that specific time and place. A modern horse is well adapted for grazing and running fast on open plains, but relocate one to the Eocene cloud forests where Eohippus thrived and it would do very badly.

Furthermore, it has been known for over a century that horses as a group did not consistently grow larger over time or otherwise become more Equus-like. Instead, horses diversified into a variety of forms over the group’s 55 million year existence, each group adapting to different environmental niches across the northern hemisphere. Large and small, forest-dwelling browsers and plains-dwelling grazers, these and all manner of other horses overlapped in time and space over the course of the Cenozoic. As J.W. Gidley of the American Museum of Natural History had worked out as early as 1907, horse evolution was not a linear progression but a tangled bush (just like the evolution of most other clades).

A modern horse phylogeny. From Macfadden 2005, via Laelaps.

A modern horse phylogeny. From MacFadden 2005, via Laelaps.

So where did the orthogenetic depiction of horse evolution come from, and why is it still with us today? The answer highlights the importance of museum exhibits and specimen provenance in the public’s understanding of paleontology, with a dose of jealous personalities for good measure.

In 1859, Charles Darwin published On the Origin of Species, in which he articulated the process of evolution by natural selection virtually exactly as we understand it today. Darwin’s book incited a whirlwind of debate in both scientific and public circles because of its implication that the diversity of life could be attributed to natural forces, rather than an unknowable divine power. Within a decade, however, the vast majority of the scientific community was convinced by the soundness of Darwin’s theory, and to this day billions of individual observations of the natural world tell us that evolution is assuredly true.

One of the many lines of evidence covered in On the Origin of Species is the fossil record, with which we can trace the evolution and extinction of organisms over time, including the ancestors of modern life. However, Chapter 9 of Darwin’s book, “On the Imperfection of the Geological Record” (full text pdf) reads like like a lengthy apology for the incomplete nature of fossil preservation. Today, the use of organized, cladistic methodologies allow paleontologists to piece together detailed phylogenies from fossils, but in Darwin’s day, the evidence was patchier, and he opted to de-emphasise the fossil record’s usefulness to avoid such criticism. As Darwin put it, “we have no right to expect to find in our geological formations an infinite number of of those fine transitional forms.” Unfortunately for paleontology specialists, this led other biologists to believe that fossils could not make any independent contribution to the understanding of evolution. Largely shut out of the biggest biological discovery of all time, paleontologists became stewards of a “second-class discipline” (Sepkoski 2012, 9).

Paleontologists in the late 19th century.

Since biologists interested in evolution considered paleontology mostly irrelevant, late 19th-century paleontologists were left with three options. They could support evolution as best they could and accept that other biologists might not take notice, they could ignore theoretical discussion entirely and focus on purely descriptive studies of morphology, or they could be spiteful and seek alternatives to Darwinian evolution. The second course of action was the most popular well into the 20th century. E.D. Cope seems to be  an example of the third approach, favoring an odd sort of neo-Lamarckism in his book The Origin of the Fittest. Such conceptions of directional change, such as Cope’s Law, are counter to evolution as proposed by Darwin and as understood today. However, a handful of paleontologists stuck with it and endeavored to provide meaningful fossil evidence for evolutionary theory.

Throughout the 1860’s, paleontologist O.C. Marsh amassed an impressive array of fossil horses from Wyoming and elsewhere in the American west. Horse fossils had been found in Europe much earlier, but Marsh’s horse collection was much more complete, and was probably the best fossil record compiled for any vertebrate group at the time. In 1870, the influential British naturalist Thomas “Darwin’s Bulldog” Huxley visited Marsh in New Haven and was suitably impressed: Marsh’s fossils ranged from the Eocene up until the Pleistocene, providing a clear picture of how the horse family had evolved over time. While Darwin had been hesitant to make too big a deal about the fossil record as evidence for evolution, the horse fossils were blatant examples of animals changing over time.

During the same visit, Huxley gave a lecture in New York in which he cited the horse fossils as a fantastic new line of evidence in support of evolution. Unfortunately, Huxley’s lecture (while admittedly aimed at a general audience) tread into some severely teleologic territory. As quoted in The Gilded Dinosaur (Jaffe 2000, 162), Huxley told his audience that “the horse is in many ways a most remarkable animal in as much as it presents us with an example of one the most perfect pieces of machinery in the animal kingdom.” He went on to explain how horse ancestors, from the little four-toed Hyracotherium in the Eocene to increasingly large horses like Merychippus and Pliohippus, gradually perfected the design of the modern horse. According to Huxley, over the course of the Cenozoic horses got bigger, faster, leggier, and generally better at being horses as we know them today. Problematically, this essentialist narrative rather misses the point of evolution as described by Darwin. 

Marsh, like Huxley, was an early advocate of evolution,  but his narrative of horse evolution was more on the mark. Marsh concluded that the smaller early horses with brachydont teeth were well suited for life in the rainforests that covered the western United States 50 million years ago. Horses like we know them today emerged as a direct result of the Earth getting cooler and drier over the course of the Cenozoic, and by the end of the Pleistocene the lineages of forest horses were completely extinct. Equus is with us today not because it is the best horse for any circumstance, but because it was most successful during the ice ages that shaped the modern flora and fauna (it also helped that humans figured out that horses are useful and ensured their survival through domestication).

Unfortunately, Marsh was never enthusiastic about public education, and so the progressive view of horse evolution was the one that made it into the public sphere. The history of horses remained a popular example of evidence for evolution, trotted out over the years by prominent biologists like George Simpson and Stephen Gould. Indeed, it was the first good evolutionary story known from fossils, although by no means the last or the best. In the earliest 1900s, Henry Osborn had a major role in solidifying the orthogenetic horse evolution story in the public eye when he curated the exhibit on the subject at the American Museum of Natural History. It is on the basic premise of this exhibit that the textbook, museum, and web descriptions of linear horse evolution that persist to this day are based.

Photo by the author.

The fossil horses of AMNH. Photo by the author.

After the modern biological synthesis, paleontologists realigned with the rest of biology, and the odd pseudo-evolutionary ideas that persisted in paleontological circles began to fall by the wayside. However, orthogenetic ideas remain common in natural history exhibits on horse evolution to this day (in about 62% of them, according to MacFadden et al. 2012). The reason these exhibits have stuck around isn’t entirely clear. MacFadden and colleagues suggest suggest a lack of inertia or funding for the renovation of exhibits is a factor, but they also point out that even some newer exhibits fall back on linear horse evolution.

The biggest problem is that orthogenetic evolution makes more intuitive sense to non-specialists. We often use the word “evolution” to imply improvement, so it would follow that horses should get bigger and better over time. This is an important misconception to overcome, because, as if we need a reminder, only 15% of Americans believe humans evolved from other animals via strictly natural processes, and an even smaller number can correctly articulate how evolution works. Evolution is the fundamental principle underlying everything we see in the natural world, and it is imperative that a correct understanding of how it works is the basis of any biology education. With the proper background, the real story of horse evolution is a great example of how changing climates effect organisms and ecosystems over time. This is helpful for interpreting the ever-important subject of climate change, but it won’t click until the linear horse evolution story is trampled out for good.

References

Jaffe, M. 2000. The Gilded Dinosaur: The Fossil War Between E.D. Cope and O.C. Marsh and the Rise of American Science. New York, NY: Three Rivers Press.

MacFadden, B.J., Oviedo, L.H., Seymour, G.M. and Ellis, S. 2012. “Fossil Horses, Orthogenesis and Communicating Evolution in Museums.” Evolution, Education and Outreach 5:29-37.

Sepkoski, D. 2012. Rereading the Fossil Record: The Growth of Paleobiology as an Evolutionary Discipline. Chicago, IL: University of Chicago Press.

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Filed under AMNH, history of science, mammals, museums, science communication, systematics