Tag Archives: NMNH

The Carnegie Quarry Diaspora

About 150 million years ago, a severe drought ravaged the western interior of North America. In eastern Utah, malnourished dinosaurs gathered near a dwindling river. Unwilling or unable to leave the water source, they eventually died of thirst or disease. When rain finally returned to the region, three or four successive flash floods washed dozens of animal carcasses into a relatively small depositional area to the southeast. Today, this site is known as the Carnegie Quarry at Dinosaur National Monument, and it is one of the most incredible fossil sites in the world.

Dinosaur National Monument interns collect data on the quarry wall.

Dinosaur National Monument interns collect data on the quarry wall. Source

Today, a structure encompassing a 180-foot section of the deposit (less than half its total length) allows visitors to view nearly 1400 dinosaur bones in situ. However, the fossils on display at Dinosaur National Monument represent only a portion of the material found at the Carnegie Quarry. Between the site’s discovery in 1908 and the establishment of the quarry wall exhibit, more than 20 reasonably complete dinosaur skeletons and dozens more incomplete specimens were excavated and distributed to museums in the US and Canada. No less than eleven mounted skeletons have been created from this material, and they are all still on display today. Although they are thousands of miles from their place of discovery and exhibited in four different cities, these mounts all represent individuals that lived and died in the same environment. They may have even encountered each other in life!

The Discovery

Earl Douglass was already an established fossil hunter when the Carnegie Museum of Natural History hired him in 1902. Late in the 1909 field season, Douglass was prospecting near the confluence of the Green and Yampa Rivers when he spotted a series of sauropod vertebrae eroding out of the rocks. Once Douglass and his crew began excavating the fossils, it became apparent that they had not just one remarkably complete dinosaur, but several. Douglass called it a “beautiful sight,” and CMNH director William Holland could barely contain his glee in his reports back to the Pittsburgh museum. Under Douglass’s management, CMNH crews worked at what became known as the Carnegie Quarry for 13 years. The dinosaur fossils were jumbled and often overlaid one another, so the excavators had to work on multiple skeletons simultaneously. The especially hard sandstone also slowed their work, and the team regularly resorted to huge horse-drawn plows and even dynamite to reach the fossils. Eventually railway tracks were installed to help transport blocks of sandstone out of the quarry.

In 1915, Holland successfully petitioned Woodrow Wilson to preserve the site as a national monument. CMNH crews continued to excavate until early 1923. At that point, their primary benefactor Andrew Carnegie had died, and funding for field work was dwindling. Other museums collected from the quarry periodically in the years that followed, but Douglass’s idea to contain the remaining fossils in an on-site museum was not realized until 1958.

The Mounts

CMNH

CMNH Apatosaurus. Historic photo from McGinnis 1982; modern photo source.

Apatosaurus louisae – CM 3018

The CMNH Apatosaurus was the first dinosaur discovered at the Carnegie Quarry. After Douglass first spotted the articulated caudal vertebrae in August of 1909, his crew spent several months extracting the rest of the skeleton from the rocks. The excavation continued into early 1910, and by the time they were finished they had the most complete Apatosaurus ever found – a title the specimen holds to this day. Holland mounted the 77-foot skeleton alongside the museum’s Diplodocus in just three years, at the time a record for a sauropod mount.

Holland famously left his Apatosaurus headless for decades due to a disagreement with Henry Osborn of the American Museum of Natural History. Douglass recovered a skull that almost certainly belonged to the Apatosaurus, but Holland opted not to use it because it contradicted the sculpted head already in place on the AMNH Apatosaurus mount. After Holland’s death in 1932, museum staff quietly added a casted Camarasaurus skull as a placeholder. This was finally replaced with a proper Apatosaurus skull in 1979. More recently, the team at Phil Fraley Productions disassembled and restored the Apatosaurus, along with the rest of the classic CMNH dinosaurs. Since 2007, this specimen has been back on display in a more graceful modern pose.

Fancy fisheye photo.

AMNH Barosaurus. Source

Barosaurus lentus – AMNH 6341

When the CMNH team discovered this skeleton in 1912, they assumed it was yet another specimen of the well-known Diplodocus. It was harvested for parts, with portions sent to CMNH, the United States National Museum, and the University of Utah to supplement their displays. When the specimen turned out to be the more obscure sauropod Barosaurus, it languished in pieces for many years. Barnum Brown of AMNH was making a circuit of the fossil collections at various natural history museums when he rediscovered this specimen. Through a series of purchases and trades, the Barosaurus was reunited at AMNH in 1929.

Nevertheless, AMNH quickly abandoned plans to mount the Barosaurus – the museum already had a sauropod on display, and there wasn’t enough floor space for another one. It wouldn’t go on display until 1991, when Lowell Dingus conceived of the idea to mount the Barosaurus in a spectacular rearing pose as part of the renovation of the Theodore Roosevelt Rotunda. Peter May took on the project – one of the first mounts produced by his company Research Casting International. The resulting display, actually a cast, is the tallest free-standing dinosaur mount in the world.

ROM Barosaurus.

ROM Barosaurus. Source

Barosaurus lentus – ROM 3670

Douglass recovered a second partial Barosaurus skeleton in 1912, which consisted of a mostly complete torso and parts of each leg. It stayed in the CMNH collections for many years, until they traded it to the Royal Ontario Museum in 1962. ROM staff intended to mount the skeleton, but once again this was cancelled due to a lack of space. David Evans was developing a new ROM paleontology exhibit in 2007 when he learned that the museum had most of a Barosaurus sitting in its collections. With only weeks remaining before the exhibit’s opening, Evans tapped Research Casting International to mount the sauropod, supplemented with a replica neck and tail from the AMNH version.

Allosaurus fragilis – CM 11844

Several Allosaurus specimens are known from the Carnegie Quarry, but the one on display at CMNH is one of the largest. Douglass and his team excavated this 35-foot skeleton between 1913 and 1915. The mount was built in 1938. Although the specimen included a partial skull, the exhibit team swapped it with a cast of a more complete skull (also found in the Carnegie Quarry) from the collections of the University of Utah. This mount also includes casts of the arms of USNM 4734, an Allosaurus collected for O.C. Marsh.

Stegosaurus ungulatus – CM 11341

The CMNH Stegosaurus is a composite of several individuals excavated from the Carnegie Quarry between 1920 and 1922. Museum staff completed the 21 foot-long mount in 1940, using a skull cast from USNM 8612. Casts of this skeleton were distributed to several other museums at some point, one of which is on display at the University of Nebraska State Museum. Phil Fraley’s company remounted the CMNH original in 2007.

Carnegie Camarasaurus.

Carnegie Camarasaurus. Source

Camarasaurus lentus – CM 11338

This juvenile Camarasaurus is the most complete sauropod ever found. It is displayed as a relief mount almost exactly as it was discovered, with two exceptions. The left leg was swapped with a more complete one from another individual, and the tail was re-positioned to create a more aesthetically pleasing mount. Casts of this skeleton are displayed at museums throughout the United States, including Dinosaur National Monument, but the original is at CMNH. This specimen is also notable because its left scapula is preserved in its life position, making it a helpful model for skeletal reconstructions and exhibit mounts.

NMNH Camarasaurus. Photo by the author.

NMNH Camarasaurus. Photo by the author.

Camarasaurus lentus – USNM 13786

The second best Camarasaurus also comes from Carnegie Quarry, but it is a considerably larger individual. Only the tail and a few odds and ends were missing. CMNH kept the specimen for several years before trading it to USNM in 1933 for a set of Pliocene horse skeletons. Norman Boss prepared the specimen in full view of the public during the 1936 Texas Centennial Exposition – one of the first known examples of such an exhibit. The completed mount appeared at USNM in the 1950s, sporting the tail of another Camarasaurus. At over 30 feet long, this skeleton is one of the largest dinosaurs on display at the Smithsonian. Unfortunately, the death pose somewhat limits the effect. The Camarasaurus was taken off exhibit in late 2014 for conservation and remounting. When it returns, it will be standing on its feet for the first time in 150 million years, taking its rightful place as one of the museum’s most impressive dinosaurs.

DMNH Diplodocus. Source

DMNH Diplodocus. Source

Diplodocus longus – DMNH 1494

Since this Dipldodocus was found somewhat disarticulated, Douglass suggested that the carcass may have been twisted apart while rolling downstream. AMNH held on to this skeleton for some time before trading it to the Denver Museum of Nature and Science in 1936 for two mammoth skeletons. Preparator Phillip Reinheimer mounted the skeleton with the help of 40 workers assigned to the museum through the Works Progress Administration. Additional Diplodocus fossils collected by William DeWeese (actually the first dinosaur specimens acquired by the museum) were also used to complete the mount. The Diplodocus remained on view until 1989, when Ken Carpenter and others restored and remounted the sauropod, elevating its tail and making its neck sweep gracefully to the left. The improved mount has been on display since 1995.

CMNH Camptosaurus.

CMNH Camptosaurus. Historic photo from McGinnis 1982; modern photo source.

Camptosaurus aphanoecetes – CM 11337

Douglass found this controversial small ornithopod in 1922, and correctly matched it with an isolated leg several feet away. It was first identified as Camptosaurus medius, but in 2008 Ken Carpenter reassigned it to the new species C. aphanoecetes. A 2011 phylogenic study by Andrew McDonald moved this specimen to a new genus, Uteodon. Carpenter, however, asserts that McDonald’s analysis was based on an incorrectly associated Dryosaurus braincase.

CMNH staff assembled the fossils into a relief mount in 1940. The skull, hindfeet, and tail were all sculpted. During the 2007 renovation, the Phil Fraley Productions team extracted the fossils from the plaster slab, even managing to preserve the delicate ossified dorsal tendons. They then created a new, three-dimensional mount, which features a revised replica skull.

Modern photo by the author.

CMNH Dryosaurus. Historic photo from McGinnis 1982; modern photo by the author.

Dryosaurus altus – CM 3392

This Dryosaurus skeleton is the most complete of several collected at Dinosaur National Monument. The tail is missing, and given the completeness of the rest of the skeleton it may well have been destroyed when Douglass’s crew was blasting through rock to get to the bone layer. The Dryosaurus entered the CMNH collections in 1922, and was assembled as a 9 foot-long relief mount in 1940. In 2007, Fraley’s team removed the fossils from the plaster matrix, and just as they did with the Camptosaurus, constructed a standing mount. To date, this is the only mounted Dryosaurus specimen in the world. It is displayed alongside a juvenile Ceratosaurus cast acquired from Western Paleontological Laboratories.

National Museum of Natural History in Washington, DC.

NMNH Diplodocus. Photo by the author.

Diplodocus sp. – USNM 10865

The National Museum of Natural History’s Diplodocus was one of the last articulated skeletons removed from the Carnegie Quarry. When the CMNH crew closed up shop, Charles Gilmore of the Smithsonian moved in to recover one of the sauropod skeletons Douglass left behind. In 1923, Gilmore’s team excavated a partial Diplodocus, and also cherry-picked a few extra bones from an adjacent specimen. The process of mounting the skeleton at USNM took six years of continuous work, and Gilmore would later describe it as the most ambitious undertaking his department hadever attempted. The 70-foot Diplodocus mount was completed in 1931, and remained unchanged for more than 80 years. It was finally taken down in December 2014, and will return in a new pose in 2019.

Addendum: Mike Taylor recently called attention to a gorgeous map of the entire deposit prepared by Ken Carpenter, which was what prompted this post. Check it out here.

References

Carpenter, K. (2013). History, Sedimentology, and Taphonomy of the Carnegie Quarry, Dinosaur National Monument, Utah. Annals of the Carnegie Museum 81:3:153-232.

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

Gilmore, C.W. (1941). “A History of the Division of Vertebrate Paleontology in the United States National Museum.” Proceedings of the United States National Museum 90.

McGinnis, H.J. (1982). Carnegie’s Dinosaurs: A Comprehensive Guide to Dinosaur Hall at Carnegie Museum of Natural History, Carnegie Institute. Pittsburgh, PA: The Board of Trustees, Carnegie Institute.

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Filed under AMNH, CMNH, collections, dinosaurs, DMNS, exhibits, field work, fossil mounts, history of science, museums, NMNH, ornithopods, sauropods, theropods, thyreophorans

So long, Diplodocus

USNM 10865 in the Hall of Extinct Monsters, circa 1932. Photo courtesy of the Smithsonian Institution Archives.

USNM 10865, shortly after its introduction in 1931. Photo courtesy of the Smithsonian Institution Archives.

Since the National Museum of Natural History fossil halls closed for renovation this past April, I’ve made a habit of checking the webcam in Hall 2 every couple weeks or so. For a while, it didn’t look like much was happening – the first waves of de-installation occurred out of view, toward the back of the gallery. Eventually, however, the iconic dinosaur mounts started coming down. The Allosaurus vanished in mid-July. The Stegosaurus and Camptosaurus were gone in September. By late October, the exhibit team had started cutting back the elevated platform and surrounding walkway where most of the standing dinosaur mounts had stood. This was when the process got really interesting, because previous renovations to this space over the past century have always been additive. Old exhibit panels were boarded over and forgotten decades ago, and even some elements of the 1911 Hall of Extinct Monsters, such as the John Elliot fresco “Diana of the Tides”, are still buried in these walls. To hear about these time capsules of science history being unsealed over the past few months has been absolutely thrilling.

But when I checked the webcam last Tuesday, I was met with a slight sinking feeling. The Diplodocus, the centerpiece of this hall for the last 83 years, was gone.

Hall 2 at NMNH, as of December 23, 2014.

Hall 2 at NMNH, as of December 23, 2014. Source

After it was excavated from Dinosaur National Monument in 1923, USNM 10865 took Charles Gilmore, Norman Boss, Thomas Horne, and John Barrett nearly a decade to prepare and mount. Aside from an an adjustment to the neck supports in the early 80s (making it hang from the ceiling, rather than being propped up from the floor), the Diplodocus remained in place and unmodified for longer than the average American lifespan. Generations of visitors have gazed up at it, and those lucky enough to view it before 1963 were able to walk under it. This mount has unquestionably taken on a second life: it is an institutional and regional icon as much as it is a dinosaur that once roamed a Jurassic floodplain. And in three days, NMNH collections staff and specialists from Research Casting International cleared every trace of it – well over 200 individual bones – from the hall.

The Diplodocus, as it stood from 1963 through 1981. Image courtesy of the Smithsonian Institution Archives.

The Diplodocus, as seen from 1963 through 1981. Image courtesy of the Smithsonian Institution Archives.

I can’t help but feel a twinge of sadness to see the Diplodocus go. I’ve been visiting the sauropod since before I could talk. I knew it as a toddler, as a high school volunteer, as a fresh-out-of college-intern, and as a museum professional. Even though the fossil halls have been closed for months, I suppose it was comforting to know that the Diplodocus was still standing on the other side of those barriers. But now it’s actually gone, and that makes it really sink in that the NMNH fossil hall that I knew – the one that inspired and nurtured my life-long interest in paleontology, is gone for good.

An early sketch of

An early sketch of USNM 10865’s new home – anchoring the Jurassic ecosystem display.

Of course, the now-disarticulated Diplodocus fossils are in the best possible hands. The veteran team at RCI will conserve, restore, and eventually remount them in a stunning, dynamic pose. What’s more, the renovated fossil hall in which it will be reintroduced is going to be awesome – structurally, aesthetically, and pedagogically. It will contextualize classic specimens like the Diplodocus within a modern understanding of how the ancient past is connected to our present and future, while simultaneously honoring this space’s history and heritage. I can’t wait.

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Filed under dinosaurs, exhibits, fossil mounts, history of science, museums, NMNH, sauropods

Extinct Monsters: Basilosaurus

Click here to start the Extinct Monsters series from the beginning.

The National Museum of Natural History houses the world’s most complete assemblage of fossil marine mammals. The crown jewel of this collection is assuredly the historic mounted Basilosaurus, which was until recently the only mount of its kind composed of original fossils. Since 2008, this ancestral whale has been suspended from the ceiling of the Sant Ocean Hall, but these fossils have actually been on near-continuous display for 120 years and counting. Technically this wasn’t the first time Basilosaurus fossils were used in a mounted skeleton (Albert Koch’s absurd chimera “Hydrarchos the sea serpent” preceded it by 60 years), but it was the first time this species was mounted accurately and under scientific supervision.

Basilosaurus was named by anatomist Richard Harlan in 1834. The name means “king lizard”, since he erroneously thought the bones belonged to a giant sea-going reptile. Richard Owen later re-identified the bones as those of a whale, and coined the new name “Zueglodon” (yoke tooth). While the International Code of Zoological Nomenclature decrees that the first published name must be used, late 19th century paleontologists apparently preferred to use Owen’s junior synonym.

Note basilo

Basilosaurus cast in the original USNM, now called the Arts and Industries Building. Photo courtesy of the Smithsonian Institution Archives.

In 1884 Charles Schuchert, an Assistant Curator at the United States National Museum, went to Clarke County, Alabama in search of “Zueglodon” remains. This would be the very first fossil-hunting expedition ever mounted by the Smithsonian. Decades earlier, Koch came to the same region to collect the fossils he used to assemble Hydrarchos, and local people had been familiar with the whale bones long before that.

Schuchert did not find the complete Basilosaurus skeleton he was looking for, but he did recover a reasonably complete, albeit fragmented, skull and jaw. He returned to Alabama in 1886 and collected an articulated vertebral column, a pelvis, and enough other elements to assemble a composite skeleton. Museum staff used the fossils to produce plaster casts, and combined them with sculpted bones to construct a replica “Zueglodon.” The whale was first unveiled at the Atlanta Exposition in 1895, before finding a home in the original United States National Museum (now the Arts and Industries Building). The 40-foot skeleton hung from the ceiling of the southwest court, with the original fossils laid out in a long case beneath it.

Basilosaurus as the centerpiece of the Hall of Extinct Monsters sometime before 1930. Photo courtesy of the Smithsonian Institution Archives.

In 1910, the USNM relocated to a larger building on the north side of the national mall, which is now of the National Museum of Natural History.  The east wing of the new museum became the Hall of Extinct Monsters, and has been the home of fossil displays at the Smithsonian ever since. The Basilosaurus was selected as the centerpiece of the new display, as its great length and toothy appearance made it popular with visitors. In honor of the occasion, preparator James Gidley reworked the old plaster mount to incorporate Schuchert’s original fossils. A series of caudal vertebrae from a third Basilosaurus specimen was also used. Still labeled “Zueglodon”, the mount was completed in 1912, about a year after the Hall of Extinct Monsters first opened to the public. As Curator of Geology George Merrill explained, the wide-open floor plan of the new hall allowed visitors to walk all the way around the mount, and inspect its every aspect up close.

During the 1960s and 70s, Basilosaurus occupied a case in the fossil mammal exhibit in Hall 5. Photo courtesy of the Smithsonian Institution Archives.

In 1931, the Basilosaurus was upstaged by a new centerpiece: the mounted Diplodocus that took Charles Gilmore and his team more than a decade to assemble. The Diplodocus took the front-and-center position (where it remained until 2014), while the Basilosaurus was relocated to the south side of the hall. The Great Depression and World War II ensured that the east wing exhibits remained largely unchanged for nearly three decades after that, but the space was eventually renovated in the early 1960s as part of a Smithsonian-wide modernization campaign. In its new incarnation, the east wing’s open spaces were carved into smaller galleries dedicated to different groups of ancient life. With the central Hall 2 occupied by dinosaurs and fossil reptiles, the Basilosaurus joined the other Cenozoic mammals in Hall 5. This gallery became “Life in the Ancient Seas” in 1989, but the Basilosaurus remained in place.

The Basilosaurus was in the Ancient Seas gallery from 1989 to 2008.

For the Ancient Seas gallery, Basilosaurus was remounted with an arched tail. Photo by Chip Clark.

Life in the Ancient Seas was a very different setting for the Basilosaurus than the Hall of Extinct Monsters, reflecting the significant changes in museum interpretation that occurred during the 20th century. The historic exhibit showcased the breadth of the museum’s fossil collection in a fairly neutral environment. Interpretation was minimal, and generally intended for a scholarly audience. In contrast, Life in the Ancient Seas was an immersive educational experience (no pun intended). The Basilosaurus and other marine mammal skeletons were posed over a papier-mâché ocean bottom, while a blue and turquoise color palate and even shimmering lights contributed to the illusion of traveling through an underwater world. Combined with text panels written with a jovial, inviting tone, the net effect was an exhibit pitched to a general audience at home with multimedia.

The historic Basilosaurus

The historic Basilosaurus, remounted for display in the Ocean Hall. Photo by the author.

The Basilosaurus was moved once more in 2008, when it was incorporated in the enormous new Ocean Hall. In its 5th position in a little over a century, the skeleton now hangs from the ceiling as part of an exhibit on whale evolution. Moving the historic skeleton was not an easy task, and took about six months of work. NMNH staff collaborated with Research Casting International to disassemble the skeleton, stabilize and conserve each bone, and finally remount the Basilosaurus on a new armature. In the new mount, each bone rests in a custom cradle with felt padding, to prevent vibration damage caused by the crowds passing beneath it. Smithsonian paleontologists also reunited the whale with its hind legs, which Schuchert found alongside the articulated vertebral column in Alabama but were, until recently, thought to belong to a bird.

This latest setting for Basilosaurus is a happy medium between museums past and present. The historic gallery occupied by the Ocean Hall has been restored to its original neoclassical glory, and much like the original Hall of Extinct Monsters visitors have clear sight lines across the space. Rather than being led on rails through a scripted exhibit experience, visitors can move freely through the gallery, bouncing among the objects they find compelling. At the same time, however, the Basilosaurus is explicitly contextualized as an example of the transformative power of evolution. Presented alongside cast skeletons of Maiacetus and Dorudon, this display makes whales’ evolutionary link to terrestrial mammals crystal clear.

This post was last updated on 1/8/2018.

References

Gilmore, C.W.  (1941). A History of the Division of Vertebrate Paleontology in the United States National Museum. Proceedings of the United States National Museum No. 90.

Marsh, D.E. (2014). From Extinct Monsters to Deep Time: An ethnography of fossil exhibits production at the Smithsonian’s National Museum of Natural History. http://circle.ubc.ca/handle/2429/50177

Meet Basilosaurus, an Ancient Whale (2008). Smithsonian Institution. http://www.mnh.si.edu/exhibits/ocean_hall/meet_basilosaurus.html

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Filed under exhibits, Extinct Monsters, fossil mounts, history of science, mammals, museums, NMNH

The Last American Dinosaurs Has Arrived!

Hatcher greets visitors

Hatcher the Triceratops greets visitors at the entrance to The Last American Dinosaurs.

Dinosaurs are once again on display at the National Museum of Natural History. Opening just in time for Thanksgiving weekend, “The Last American Dinosaurs” provides a much-needed dose of paleontology while the main fossil hall is being renovated. I was fortunate enough to take part in a preview tour for social media users – you can check out the storified version, or read on for photos and my initial thoughts on the new exhibit.

Stan is cool

Stan the T. rex is sure to be a crowd-pleaser.

Babies

Triceratops growth series reveals how much we’ve learned about the lives of dinosaurs over the last 25 years.

As promised, there are plenty of dinosaurs on view. Specifically, these are the dinosaurs of Maastrichtian North America, the last of these animals to grace this continent before the extinction event 66 million years ago. In addition to the mounted skeletons of Triceratops and Tyrannosaurus discussed in the previous post, be on the lookout for a hatchling and juvenile Triceratops, an Edmontosaurus, and bits and pieces from dromaeosaurs and pachycephalosaurs.

However, the dinosaurs are just the tip of the iceberg. As lead curator Hans-Dieter Sues explained within the first few minutes of the tour, the central message of this exhibit is that dinosaurs were only one part of a complex ecosystem. To that end, the dinosaurs of The Last American Dinosaurs are outnumbered by a menagerie of of reptiles, mammals, invertebrates, and plants that shared their world, most of which are on display for the first time. These specimens come from a variety of sources. Some, including turtles and fossil leaves, were collected by NMNH paleontologists in North Dakota specifically for this exhibit. Others, like the lizard Polyglyphanodon, have been in the museum’s collection since the 1930s but have never before been put on display. I also spotted a few casts sourced from Triebold Paleontology, including the mammal Didelphodon and the alligator-like Stangerochampsa

Gilmore specimen

This Polyglyphanodon was collected by Charles Gilmore in the 1930s.

crocs

Stangerochampsa and Champsosaurus are examples of animals that survived the K/T extinction.

Much like the Human Origins exhibit, The Last American Dinosaurs incorporates the faces of Smithsonian researchers and staff throughout the displays. There are large photos showing the museum’s scientists at work in the field, and the popular windowed FossiLab has found a new home in this exhibit. In addition, a large area is deservedly devoted to scientific illustrator Mary Parrish, chronicling the methods she uses to turn fossil data into gorgeously detailed renderings of prehistoric animals and environments. Videos of Parrish and others at work can be seen here.

I’m definitely a fan of this personalized approach to science communication. In-house scientists are museums’ most important and unique resources, and placing them front-and-center reminds visitors that science is done by real and diverse people, not caricatures in lab coats. A human face goes a long way toward making the process of doing science relateable to visitors.

new stuff

Handwritten labels on these fresh from the field fossils provide a personal touch.

The phenomenon of extinction is another important theme in The Last American Dinosaurs. The exhibit details how an asteroid impact combined with several other factors to radically alter the environment worldwide, causing 70% of species to die out (fun fact: ambient temperatures in North America directly after the impact were comparable to the inside of a brick pizza oven). However, the exhibit goes on to make direct comparisons between the K/Pg extinction event and the anthropogenic extinctions of today. Habitat destruction, introduction of invasive species, and climate change caused by burning fossil fuels are instigators of environmental upheaval as powerful as any space rock.

extinction

This moa and dodo remind visitors that extinction isn’t limited to the distant past.

In this way, The Last American Dinosaurs is a warm-up for the key messages of the new fossil hall. The overarching theme of the planned exhibit is that “Earth’s distant past is connected to the present and shapes our future.” It will showcase how living things and their environments are interdependent, and change over time. Crucially, it will also demonstrate how our understanding of how life has changed over time is important for understanding and mitigating our impact on present-day ecosystems. The Last American Dinosaurs is evidently a testing ground for how these ideas will resonate with audiences.

paleoart

Historic models of Agathaumas and Triceratops by Charles Knight and Charles Gilmore.

In designing modern paleontology exhibits, museum workers have tried many approaches to squelch the idea of the dinosaur pageant show and instead convey how the science of paleontology is relevant to our understanding of the world around us. Back in 1995, the American Museum of Natural History tried a cladistic arrangement with a focus on biodiversity. More recently, the Field Museum used the process of evolution to frame the history of life on Earth. While there are certainly overlaps with what has come before, the “modern implications of environmental change over deep time” approach under development at NMNH is fairly novel, and also quite timely. Some of the displays in The Last American Dinosaurs hit pretty close to home, and I’m eager to find out how visitors respond.

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Filed under dinosaurs, exhibits, fossil mounts, mammals, marginocephalians, museums, NMNH, ornithopods, paleoart, reptiles, reviews, science communication, theropods

Hatcher, Stan, and the Changing Identities of Fossil Mounts

Photo by the author

Hatcher the Triceratops and Stan the T. rex in the NMNH fossil hall, early 2014. Photo by the author.

Although the east wing fossil halls are closed for renovation until 2019, the National Museum of Natural History will not be without a dinosaur display for much longer. An interim exhibit entitled “The Last American Dinosaurs” will open later this month, occupying the space that formally held the “Written in Bone” exhibition. The Last American Dinosaurs will cover a small but important slice of the age of dinosaurs: the final ecosystem to grace North America before the extinction event 66 million years ago. While the new exhibit will feature several show-stealing dinosaurs, the main message is that these animals lived within a complete and complex ecosystem, just like the animals of today. The exhibit will also cover the phenomenon of extinction, and how massive environmental change (whether caused by a giant space rock or by human activity) can drastically alter the course of life on Earth.

What I’d like to discuss in this post are the two dinosaurian centerpieces of the exhibit: Hatcher the Triceratops and Stan the Tyrannosaurus. Both mounts stood in the classic fossil hall for years, and I’ve already written extensively about each of them. Nevertheless, these two dinosaurs nicely encapsulate the history of mounted fossil skeletons, as well as the changing face of museum paleontology. As the ambassadors to the Smithsonian’s dinosaur collection for the next five years, I think it’s worth revisiting their origin stories.

The First Triceratops

Hatcher in Hall of Extinct Monsters

This Triceratops stood in the NMNH fossil hall for nearly 90 years. Photo courtesy of the Smithsonian Institution Archives.

The Smithsonian Triceratops hails from what we might call the golden age of museum paleontology. Mounted dinosaur skeletons were an integral part of the rise of large urban natural history museums at the turn of the 20th century. The opening of the American western frontier revealed an unprecedented treasure trove of fossils, far greater than what was previously known in Europe. As a result, paleontology became one of the first realms of science in which Americans were leaders, and patriotism was a significant factor in the growing public enthusiasm for extinct monsters. Wealthy benefactors of recently formed institutions like the American Museum of Natural History and the Field Columbian Museum envisioned the mounted skeletons of dinosaurs as an opportunity to increase attendance and public interest, and they provided ample funding to find fossils for display. These efforts were not wasted, as the golden age fossil mounts have been enjoyed for generations…and most are still on display today.

It’s easy to get caught up in the romanticism of this era of discovery and exposition. Golden age fossil mounts were forged into being entirely in-house. At a given museum, the same small group of staff was frequently responsible for finding, preparing, describing, naming and mounting a new dinosaur. As such, fossil mounts were typically exclusives to particular museums, and they garnered significant amounts of institutional and regional pride. New York had “Brontosaurus” and Tyrannosaurus. Pittsburgh had Diplodocus. And for more than 20 years, Washington, DC had the world’s only mounted Triceratops.

Hatcher in Sunday star

A spread in the June 11, 1905 Sunday Star profiled the Smithsonian Triceratops. Image courtesy of the Smithsonian Institution Archives.

Built in 1905 by Charles Gilmore and Norman Boss, the Smithsonian Triceratops has been a Washington, DC attraction for longer than the Lincoln Memorial. Like most turn of the century dinosaur mounts, it is not a single specimen but a composite of several individuals. The fossils were recovered from Wyoming by the prolific fossil hunter John Bell Hatcher, working in the employ of O.C. Marsh and the United States Geological Survey*. USNM 4842, the most complete partial skeleton available, provided the torso and pelvis, while the remains of at least six other Triceratops filled in the rest of the mount.

*Incidentally, this means the Triceratops doesn’t quite fit the story I outlined above. It was not discovered or named by Smithsonian scientists – instead, the Smithsonian inherited the fossils Marsh collected for the federal government when he was through with them.

Even though it was a slightly disproportionate chimera, for experts and laypeople alike the Smithsonian Triceratops mount was Triceratops. Virtually every illustration of the animal for decades after the mount’s debut dutifully copied its every eccentricity, including the slightly undersized head and excessively sprawled forelimbs. If you can strain your eyes to read Sunday Star article above, it’s also interesting to see how the mount was presented to the public. Even in an era when museum displays were unapologetically created by experts for experts, the Triceratops is repeatedly likened to a fantastical monster. Although the creation of the mount was an important anatomical exercise for the small community of professional paleontologists, it seems that for most visitors a display like this primarily served as whimsical entertainment.

Hatcher_tempdisplay

Hatcher was moved to his new home on the second floor at the beginning of the summer. Photo by the author.

After a brief stint in the original United States National Museum (now called the Arts and Industries Building), Gilmore and Boss’s Triceratops was transferred the east wing of the present-day NMNH in 1911. It remained there for 90 years, until the aging and deteriorating fossils were finally disassembled and retired to the collections. In their place, Smithsonian staff created an updated replica skeleton, called “Hatcher”, from digital scans of the original bones. This version is the Triceratops that will be on display in The Last American Dinosaurs.

A Prefab Tyrannosaurus?

Stan. Photo by Chip Clark.

Stan the T. rex, as seen in the classic NMNH fossil hall. Photo by Chip Clark.

Since 2000, Hatcher the Triceratops was in a permanent face-off with another replica mount, Stan the Tyrannosaurus. Unlike Hatcher, Stan is not based on fossils in the Smithsonian collection. This T. rex cast was purchased from the Black Hills Institute, a private company that  produces and sells replica fossil skeletons (as well as original specimens, which is another issue entirely). Discovered by avocational fossil hunter Stan Sacrison in 1987, Stan the dinosaur was excavated and is now owned by BHI. Since 1995, BHI has sold dozens of Stan replicas to museums and other venues. The Smithsonian acquired its version in 1999, in part because of visitor demand for the world’s most famous dinosaur, but also apparently as a consolation prize for missing out on Sue.

Clearly, much has changed in the way museums source their dinosaurs. Rather than creating fossil mounts on-site, museums frequently contract out the production to exhibit fabrication companies like Research Casting International, Gaston Design, and the aforementioned Black Hills Institute. These companies can construct mounts using fossils or casts from a particular museum’s collection, but they also offer catalogs of made-to-order skeletons. Thanks to these exhibit companies, more or less identical copies of certain dinosaurs are now on display all over the world.  In Stan’s case, the Smithsonian version has a twin just seven miles north at the Discovery Communications building in Silver Spring.

Stan can be set up in a under an hour. This version was recently displayed at Farmington Museum.

Stan replicas can be set up in a under an hour. This version was recently displayed at New Mexico’s Farmington Museum. Source

An argument could be made that this degree of replication lessens the impact and cultural value of dinosaur displays. How much allure does a mount have when identical versions can be seen at dozens of other locations, including corporate offices and amusement parks? I would counter that this is a small price to pay when we consider the substantial educational benefits of this unprecedented availability of dinosaur skeletons. Widespread casts like Stan give people all over the world the opportunity to see a T. rex in person, an experience that was until recently limited to those with the means to travel to a handful of large cities. Typically priced in the tens of thousands of dollars, dinosaur casts certainly aren’t cheap, but they are still within the means of many small to mid-sized local museums.

Furthermore, these casts are hardly rolling off of assembly lines. They are exact replicas of real fossils, and require a tremendous amount of experience and skill to produce. Mounts are manufactured as needed, and are customized to meet the needs of the specific museum. Meanwhile, museums still employ scientists who collect new fossils for their collections. The difference is that these collecting trips usually seek to answer specific research questions, rather than going after only the biggest and most impressive display specimens. Finally, museums definitely haven’t outsourced exhibit production entirely. All summer at NMNH, in-house preparators have been working in collaboration with contractors from Research Casting International to dismantle the historic fossil exhibits in preparation for the upcoming renovation.

Reassembling Stan upstairs. Photo by Abby Telfer.

Reassembling Stan for The Last American Dinosaurs. Photo by Abby Telfer.

There’s one more change for the better in modern paleontology exhibits. When the Smithsonian Triceratops was first introduced to the world in 1905, natural history displays tended to focus on the breadth of collections. Curators composed exhibits with other experts in mind, and the non-scholars that actually made up the majority of museum visitors were not directly catered to. Without any context to work with, fossil mounts were little more than toothy spectacles for most visitors. Today, museum staff create exhibits that tell stories. The Last American Dinosaurs has been explicitly designed to contextualize the dinosaurs – to show how they fit into the history of life on Earth, and why their world is meaningful today. How successful will this be? I’ll report back after the exhibit opens on November 25th.

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Filed under dinosaurs, exhibits, fossil mounts, history of science, marginocephalians, museums, NMNH, reptiles, theropods

National Fossil Day 2014

Happy National Fossil Day! This will just be a quick photo post covering the events at the National Museum of Natural History today. The National Park Service started the day with a junior paleontologist swearing-in ceremony, where students from a dozen area schools learned about the importance of protecting and preserving public lands and natural resources.

Photo by

Photo by the National Park Service.

The main show was in the Q?rius education center, where museum staff and volunteers showed off their latest work and discoveries. Visitors could see tiny mammal bones and teeth plucked from matrix collected in Haitian caves, and work through a particularly inspired activity demonstrating how geologists correlate layers in different parts of the world.

nfd2

Photo by the author.

Photo by

Photo by the National Park Service.

Resident scientific illustrator Mary Parrish had a particularly fascinating display, showcasing the methods and materials she uses to create accurate paintings of prehistoric environments. Note the aluminum foil leaves used as models to paint from, as well as the hand-made macquettes used to block out scenes and experiment with poses. Also on view was a draft of the giant Hell Creek mural that will be on display in The Last American Dinosaurs, opening in November.

nfd3

Photo by the author.

Out in the lower level lobby, the National Park Service, Bureau of Land Management, US Forest Service, National Science Foundation, Calvert Marine Museum, and Maryland Dinosaur Park had activities and displays. Here’s our display of recently discovered fossils from Cretaceous Maryland, slightly overshadowed by the Nation’s T. rex. We talked with visitors about Maryland’s role in the history of dinosaur science, the importance of the early Cretaceous as the origin of the world we know today, and our citizen science programs at the Park in Laurel.

image

Photo by the author.

Photo by the author.

Our Deinonychus replica looks a little small next to the Nation’s T. rex. Photo by the author.

National Fossil Day is all about generating awareness and enthusiasm for fossils and the study of the Earth’s natural history. In that, I think the event was quite successful. We talked to nearly 400 people, all of them enthusiastic and eager to learn about local prehistory and the process of discovering the ancient past. It was also a fun opportunity to catch up with people – the Washington area paleontology scene isn’t very big!

Thank you to the National Park Service for coordinating this event, and to the Smithsonian for hosting it!

 

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Museums and the Triceratops Posture Problem – Part 2

Triceratops at the National Museum of Natural History.

Triceratops “Hatcher” at the National Museum of Natural History. Photo by the author.

Back in July, I wrote about how the forelimb posture of ceratopsian dinosaurs like Triceratops has puzzled paleontologists for more than a century. Most quadrupedal dinosaurs held their front legs straight under their bodies, and it would make sense if Triceratops and its kin did the same. However, when researchers attempted to physically articulate skeletons for museum displays, they found that that the humerus would only fit properly with the scapula if it projected horizontally from the torso – like the sprawling limbs of a lizard. Over the years, new specimens, new research methods, and new technologies have all been used to help resolve this conundrum, but a consensus has not yet been reached. Of particular interest to me is the unusually central role mounted skeletons in museums have played in this biomechanical mystery. The previous post covered the historic Triceratops mounts; this entry will take a look at some more recent Triceratops displays in American museums.

The Hatcher Project

In 1998, a visitor looking at the Triceratops mount at the National Museum of Natural History happened to sneeze. To her alarm, the sneeze was enough to knock a small fragment of bone off the pelvis and onto the floor. The visitor thoughtfully informed security, and after a thorough conservation assessment by Kathy Hawks, it was determined that the 93-year-old mount needed to come off exhibit, and soon. The delicate fossils had served valiantly through 23 presidential administrations, but now it was time for the skeleton to be disassembled and preserved for posterity.

Retiring the classic Triceratops gave Ralph Chapman, head of the Museum’s Applied Morphometrics Laboratory, an opportunity to take on a project he had been germinating for some time. Chapman wanted to demonstrate the potential of 3-D scanning technology for paleontology research by creating a high-resolution digital duplicate of a dinosaur skeleton. Today, the process of making and studying digital copies of fossils is both widespread  and remarkably straightforward, but in the late 1990s it was practically science fiction. Nevertheless, the historic Triceratops was an ideal digitization candidate for several reasons. First, the digital assets would reduce handling of the delicate and aging original fossils. Second, exact copies of the scanned bones could be made from milled foam and plastics to create a replacement exhibit mount. Finally, a digital Triceratops would be a great opportunity to revisit the ceratopsid posture problem in a new way.

digital hatcher

A rendering of the digital Hatcher. Source

The ensuing Hatcher Project (the Triceratops was named in honor of John Bell Hatcher, who found the original fossils in the late 19th century) was a collaboration between Museum staff and several industry experts, including Lisa Federici of Scansite 3-D Services and Arthur Andersen of Virtual Surfaces, Inc. The first step was to place stickers on 100 key points on the Triceratops. These points were recorded with a surface scanner, so that the historic mount could be digitally recreated in its original pose. After that, fossil preparators Steve Jabo and Pete Kroehler carefully dismantled the skeleton. Each bone from the skeleton’s right side* was then scanned individually, producing 20 gigabytes of data (you’re supposed to gasp…again, this was the late 90s).

*Bones from the right side were mirrored to reproduce the left half of the skeleton. 

Since the original mount had been a somewhat disproportionate composite, the team made a few changes when building the new digital Hatcher. Some elements, including the undersized skull, were enlarged to match the rest of the skeleton. In addition, parts that had either been sculpted or were not actually Triceratops bones – such as the dorsal vertebrae and the hindfeet – were replaced with casts acquired from other museums. The result was the world’s first complete digital dinosaur, and shortly afterward, the first full-sized replica skeleton generated from digital assets.

Updated "Hatcher" mount's rarely seen right side. Source

Hatcher’s seldom seen right side was briefly exposed recently, before the mount was moved to a temporary second floor location. Source

In April 2000, the Hatcher team convened at NMNH to determine how the new replica mount would be posed. Chapman, Jabo, and Kroehler were joined by Kent Stevens of the University of Oregon, Brenda Chinnery of Johns Hopkins University, and Rolf Johnson of the Milwaukee Public Museum (among others) to spend a day working with a 1/6th scale model produced by stereolithography specialist Jason Dickman. The miniature Hatcher allowed the researchers to physically test the skeleton’s range of motion without the difficulty of manipulating heavy fossils.

The day was full of surprises. The team was impressed by the wide range of motion afforded by the ball and socket joint connecting the Triceratops skull to the atlas. They also found that the elbow joints could lock, which may have been helpful for shock absorption when the animal smashed things with its face. Nevertheless, when it came time to articulate the humerus and scapula, the team essentially validated Charles Gilmore’s original conclusion that sprawling forelimbs worked best (although the new Hatcher mount stands a little straighter than the historic version, and a lot straighter than the New York Triceratops). While other paleontologists had used indirect evidence (like evenly spaced trackways and wide nasal cavities for sucking down lots of oxygen) to support the idea that Triceratops was a straight-legged, fast-moving rhino analogue, articulating the actual bones showed once again that ceratopsid forelimbs had to sprawl.

Houston and Los Angeles Mounts

LACM Triceratops mount. Photo by Heinrich Mallison, many more here.

LACM Triceratops mount. Photo by Heinrich Mallison, many more here.

Hatcher is the Triceratops I am best acquainted with, and I can’t help but think of it as the definitive example of this animal. However, two new Triceratops mounts demonstrate a radically different take on ceratopsid posture. In 2011, the Natural History Museum of Los Angeles County completed a thoroughly renovated dinosaur hall, which features a brand-new Triceratops mount at its entrance. Like Hatcher, this skeleton is a composite of several specimens, in this case excavated in Montana by LACM teams between 2002 and 2004. Phil Fraley Productions, the exhibit fabrication company behind Sue and the Carnegie Museum dinosaurs, was responsible for mounting the fossils. The primary specimen (LACM 141459, which provided the skull and right forelimb) is notable because it included a completely intact and articulated front leg. Although the analysis of this important find has yet to be published, exhibit curator Luis Chiappe tellingly chose an erect, rather than sprawling, forelimb posture.

Meanwhile, the Houston Museum of Nature and Science opened its colossal, 30,000 square foot Hall of Paleontology in 2012. Among the dozens of mounted skeletons on display is Lane, reportedly the most complete Triceratops ever found. The museum purchased the skeleton from the Black Hills Institute, and the company also constructed the display mount. Robert Bakker, who curates the Hall of Paleontology, specifically requested that Lane be given a straight-legged, trotting pose. With two legs off the ground, this display emanates strength and speed.

"Lane" at Houston Museum

“Lane” at Houston Museum of Nature and Science. Source

So how did the Los Angeles and Houston exhibit teams manage to construct plausible-looking, straight-legged Triceratops mounts? Since full descriptions of either specimen have not been published, it’s hard to say for sure. From the look of it, however, the new mounts both have narrower, flatter rib cages (as suggested by Paul and Christiansen), which allows more room for the elbow. Likewise, the shoulder girdles are lower than Hatcher’s, and they seem to have been rotated closer to the front of the chest. Also note that the forelimbs of the Los Angeles and Houston mounts are not completely erect – they are strongly flexed at the elbow, as is typical of many quadrupedal mammals.

These new mounts don’t mean the Triceratops posture problem is resolved, though. The angle of the ribs and the position of the scapula are apparently both touchy subjects, so alternate interpretations are sure to arise in the future. After all, Triceratops forelimb posture isn’t just an esoteric bit of anatomical trivia: it has major implications for the speed and athleticism of an extremely successful keystone herbivore. Understanding the limitations on this animal’s movement and behavior can contribute to our understanding of the ecosystem and environmental pressures in late Cretaceous North America. As such, I am eagerly awaiting the next round in this 100-plus year investigation.

A big thank you to Rebecca Hunt-Foster and Ralph Chapman for sharing their time and expertise while I was writing this post!

References

Chapman, R. Personal communication.

Chapman, R., Andersen, A., Breithaupt, B.H. and Matthews, N.A. 2012. Technology and the Study of Dinosaurs. The Complete Dinosaur, 2nd Edition. Bloomington, IN: Indiana University Press.

Fujiwara, S. and Hutchinson, J.R. 2012. Elbow Joint Adductor Movement Arm as an Indicator of Forelimb Posture in Extinct Quadrupedal Tetrapods. Proceedings of the Royal Society 279: 2561-2570.

Hunt-Foster, R. Personal communication.

Paul, G.S. and Christiansen, P. 2000. Forelimb Posture in Neoceratopsian Dinosaurs: Implications for Gait and Locomotion. Paleobiology 26:3:450-465.

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Filed under anatomy, dinosaurs, fossil mounts, history of science, marginocephalians, museums, NMNH, reptiles

Extinct Monsters: Brachyceratops

Click here to start the Extinct Monsters series from the beginning.

Most of the mounted dinosaur skeletons at the National Museum of Natural History (NMNH) represent taxa that are well-known to casual paleontology enthusiasts. But nestled amongst household names like Triceratops, Stegosaurus and Diplodocus is an easily-overlooked horned dinosaur that was historically called Brachyceratops montanensis (it’s currently labeled Styracosaurus sp). Tucked away in a glass case behind the giant Triceratops, this pocket-sized ceratopsian may not be the most spectacular display in the exhibit, but it is nevertheless an important one for the Museum. Discovered in 1913 by the Smithsonian’s own Curator of Fossil Reptiles Charles Gilmore, Brachyceratops represents one of only a few dinosaur species excavated, prepared, described and exhibited entirely in-house at NMNH. It is therefore unfortunate that modern researchers have banished the name Brachyceratops to the realm of taxonomic obscurity. What’s more, the days of the Brachyceratops mount, on exhibit since 1922, are numbered: when the NMNH paleontology halls closed for renovation in April 2014, this specimen was be retired to the collections, and is not planned for inclusion when the exhibit reopens in 2019.

The Brachyceratops mount today. Photo by the author.

The Brachyceratops mount today. Photo by the author.

During his tenure at NMNH, Gilmore was an inexhaustibly productive writer, publishing at least 170 scientific articles, including numerous important descriptions and reassessments of fossils discovered by O.C. Marsh’s teams in the 19th century. However, Gilmore was much happier studying fossils in his lab than excavating new finds in the field, taking part in a scant 16 NMNH-sponsored field expeditions over the course of his career. A 1913 trip to the Cretaceous Two Medicine Formation in Northeast Montana was therefore unusual for Gilmore. He was following in the footsteps of Eugene Stebinger of the US Geological Survey, who had reported the previous year that the region was only minimally explored but clearly awash in vertebrate fossils.

On this inaugural fossil prospecting trip, Gilmore’s team located abundant remains of fish, small reptiles and dinosaurs, especially hadrosaurs and ankylosaurs. The most notable find, however, was a small bone bed (about six feet square) of ceratopsian fossils, representing at least five individuals. Gilmore described this find in a 1917 monograph, naming the dinosaur Brachyceratops montanensis. Today we know that ceratopsians were quite diverse, particularly during the Campanian, but in the early 20th century the true extent of the group was only just being revealed. Still, it was clear to Gilmore that at an estimated six feet in length, Brachyceratops was an unusually small ceratopsian. He proposed that it may have fed on different plants or occupied a different niche than larger contemporaries like Centrosaurus and Styracosaurus.

pretty art

Reconstruction of Brachyceratops holotype skull. Plate from Gilmore 1917.

In 1917, most of the dinosaur mounts on display at NMNH came from fossils collected by Marsh for the US Geological Survey, and many represented species also on display in New York, Pittsburgh and New Haven. Accordingly, Gilmore was doubtlessly enthused by the prospect of displaying a dinosaur exclusive to Smithsonian. He awarded the task of creating a Brachyceratops mount to preparator Norman Boss, who would spend 345 working days on the project. Of the five individuals found in Montana, USNM 7953 was selected as the basis for the mount because it was the most complete, with the sacrum, pelvis, femora and complete set of caudal vertebrae found articulated in situ. Helpfully, Gilmore published a list of precisely which parts of the mount came from which individual specimen (see below). This was a marked contrast from some of his contemporaries at other museums, who would not bother to record such information, or even actively obscure how many disparate specimens they were using to build their mounts.

Gilmore's helpful list

A helpful breakdown of the Brachyceratops mount from Gilmore 1922.

Boss based his restoration of Brachyceratops closely on the complete, articulated Monoclonius (=Centrosaurus) specimen (AMNH 5351) discovered by Barnum Brown in 1914. In particular, Boss replicated the angle of the scapulae and the number of vertebrae (22) on the American Museum of Natural History skeleton. Missing bones and portions thereof were sculpted in plaster, easily recognized by their solid color and smooth texture. Just as Gilmore and Boss had done with their 1905 Triceratops mount, the Brachyceratops was given strongly flexed elbows. According to Gilmore, a very large olecranon process on the ulna would have forced all ceratopsians into this somewhat awkward stance. Of particular note is the restoration of the skull, which was found shattered into dozens of pieces, many smaller than one inch. A close look at the specimen reveals how Boss painstakingly reassembled these fragments. Unfortunately, this is difficult in the exhibit hall because the mount is posed with the side of the skull that is mostly plaster facing visitors.

Norman Boss Brachyceratops courtesy Smithsonian archives

Norman Boss puts the finishing touches on the Brachyceratops mount. Photo courtesy of the Smithsonian Archives.

The completed Brachyceratops mount was placed on exhibit in 1922, on the same pedestal in the Hall of Extinct Monsters as the Triceratops. The substrate beneath the mount was colored and textured to match the Two Medicine Formation sandstone in which the fossils were found. Gilmore also prepared one of his charming models of Brachyceratops, mirroring the pose of the mount, but it is unclear whether it was ever exhibited.

woo triceratops

Brachyceratops on exhibit with Triceratops. Plate from Gilmore 1922.

The Brachyceratops has remained on view through each subsequent renovation of the fossil halls, always placed close to Triceratops. This close association has prompted many visitors to mistake the diminutive Brachyceratops for a baby Triceratops, and in fact these visitors are on the right track. While Gilmore always described Brachyceratops as an unusually small but full-grown ceratopsian, Scott Sampson and colleagues confirmed in 1997 that all five specimens were juveniles. A century’s worth of new fossil discoveries has provided modern paleontologists with a thorough understanding of ceratopsian ontogeny, and characteristics like the unfused nasal horn clearly mark the mounted Brachyceratops as a young animal. Unfortunately, Gilmore’s Brachyceratops specimens lack any good diagnostic features that could link it to an adult form. According to Andrew McDonald, the most likely candidate is Rubeosaurus ovatus, which was, incidentally, discovered by Gilmore on a 1922 repeat trip to the Two Medicine site. Nevertheless, without the ability to recognize other growth stages of the same species, the name Brachyceratops is unusable and is generally regarded as a nomen dubium.

It is not difficult to surmise why the Brachyceratops would end up near the bottom of the list of mounts to include in a renovated gallery. It is not especially large or impressive, it doesn’t have a recognizable name (or any proper name at all, really) and it doesn’t tell a critical story about evolution or deep time. With limited space available and new specimens being prepped for display, little Brachyceratops will have to go. It’s not all bad, though. Taking these fossils off exhibit will make them more accessible to researchers, and allow them to be closely examined in all aspects for the first time in decades. Perhaps one day soon we will have a clearer idea of the identity of one of Gilmore’s great finds.

References

Gilmore, C.W. (1917). Brachyceratops, a Ceratopsian Dinosaur from the Two Medicine Formation of Montana, with Notes on Associated Fossil Reptiles. Washington, DC: US Geological Survey.

Gilmore, C.W. (1922). The Smallest Known Horned Dinosaur, Brachyceratops. Proceedings of the US National Museum 63:2424.

Gilmore, C.W. (1930). On Dinosaurian Reptiles from the Two Medicine Formation of Montana. Proceedings of the US National Museum 77:2839.

McDonald, A.T. (2011). A Subadult Specimen of Rubeosaurus ovatus (Dinosauria: Ceratopsidae), with Observations on other Ceratopsids from the Two Medicine Formation. PLoS ONE 6:8.

Sampson, S.D., Ryan, M.J. and Tanke, D.H. (1997). Craniofacial Ontogeny in Centrosaurine Dinosaurs: Taxonomic and Behavioral Implications. Zoological Journal of the Linnean Society 12:1:293-337.

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Filed under dinosaurs, exhibits, Extinct Monsters, field work, fossil mounts, history of science, marginocephalians, museums, NMNH, reptiles

The Gilmore Models: Where are they now?

Regular readers of this site (if there are any) undoubtedly know Charles Whitney Gilmore as the Smithsonian paleontologist who, between 1903 and 1964, led in the creation of most of the mounted dinosaur skeletons that remain on display at the National Museum of Natural History today. You don’t necessarily have to be in Washington, DC to see Gilmore’s reconstructions, however. In addition to being an expert anatomist and fossil preparator, Gilmore was a formidable sculptor, and during his tenure at the Smithsonian he produced a number of gorgeous life reconstructions of prehistoric animals. Plaster copies of these models were gifted or sold to large and small museums in North America and Europe, including the Sternberg Museum of Natural History, the University of Kansas Natural History Museum and the Hunterian Museum at the University of Glasgow. These models were typically displayed alongside isolated fossil elements to give a sense of the entire animal at institutions where complete mounts were unfeasible.

Gilmore with Diplodocus vertebrae.

Charles Gilmore, or Chucky G, as he was known to his friends.

Unfortunately, many of the museums that acquired copies of Gilmore’s models in the 1920s and 30s seem to have lost the detailed provenance of these acquisitions (not a rare occurrence, as museums must track literally millions of objects and historic records on paper do not always survive). The Hunterian Museum has the best records regarding these models that I am aware of, and incidentally their online catalog is the source of most of the photographs in this post.

Stegosaurus model in plaster of paris. Image courtesy of the Hunterian Museum and Art Gallery.

Stegosaurus model in plaster of paris. Image courtesy of the Hunterian Museum and Art Gallery.

While Gilmore’s models are obviously far from accurate by modern standards, a closer inspection reveals that Gilmore was familiar with every inch of the fossils in his care, and put that knowledge to use in his sculptures. The Stegosaurus above, for instance, is a perfect match for Gilmore’s full-sized mount in terms of pose and proportion. Undoubtedly, physically assembling an actual skeleton is among the best ways to become familiar with how an animal would work in three dimensions. In particular, note that unlike many contemporary reconstructions, Gilmore did not fudge the number or position of the plates; they’re all accounted for.

Stegosaurus model in plaster of paris. Image courtesy of the Hunterian Museum and Art Gallery.

Triceratops model in plaster of paris. Image courtesy of the Hunterian Museum and Art Gallery.

The Triceratops model exhibits a number of interesting choices. The classic bowed ceratopsian forelimbs (which Gilmore first proposed after finding no other way to articulate them in his 1905 Triceratops mount) are clearly in evidence, but my eye is drawn to the scrawny, lizard-like hindlimbs. Comparing this model to Gilmore’s mount, there would appear to be virtually no muscle back there. The size of the head is yet another remnant of the mounting process. Since his Triceratops mount was a composite of numerous specimens, Gilmore used the skull of an inappropriately small animal, and apparently carried the chimeric proportions to this sculpture. The lack of cheeks and extremely thick neck are also characteristic of older ceratopsian reconstructions, although I can’t comment on precisely when or why that look went out of style.

Stegosaurus model in plaster of paris. Image courtesy of the Hunterian Museum and Art Gallery.

Diplodocus model in plaster of paris. Image courtesy of the Hunterian Museum and Art Gallery.

This Diplodocus has a much more defined shape than most mid-century sauropod reconstructions. Note in particular the sloping back, which peaks at the sacrum. This differs from the 1907 Diplodocus mount at the Carnegie Museum of Natural History, which had a completely horizontal spinal column. When Gilmore led the creation of the Smithsonian Diplodocus mount, he had the opportunity to use a vertebral column that was found articulated in situ, and was thus able to more accurately portray the shape of the animal’s midsection.

Ceratosaurus
Ceratosaurus. Image courtesy of the Hunterian Museum and Art Gallery.

Gilmore’s Ceratosaurus is the liveliest of the set, and is the only one that doesn’t strictly adhere to the pose of a corresponding fossil mount. Delivering a killing blow to a hapless ornithopod, one can easily imagine the energetic pounce that preceded this scene. I will point out, though, that this guy’s hindquarters are enormous. 

Gilmore's stub-tailed Dimetrodon. Image from Gilmore 1939.

Gilmore’s stub-tailed Dimetrodon model. 

Gilmore also sculpted some non-dinosaurs, including at least one prehistoric horse and the Dimetrodon pictured above. Note the teensy stub of a tail, which this model actually shared with Gilmore’s mount of the pelycosaur. The lips obscuring most of the teeth except for a couple incisors is an unusual choice, and I’m not sure what inspired it. This image is from Gilmore’s 1939 paper on Dimetrodon, and the Basiliscus basiliscus in the corner provides a helpful comparison to a contemporary animal with a similar dorsal sail.

In addition to the models shown here, Gilmore created sculptures of “Anatosaurus”, “Brachyceratops” and a Cenozoic horse, as well as busts of Styracosaurus and Corythosaurus (and there may well have been others I haven’t seen). As mentioned, copies of these mounts were distributed to museums and possibly private collections throughout the 20s and 30s, and I have no idea how many were actually made. A few museums, such as the Sternberg Museum, actually have these models on display, but at other institutions they have been relegated to storage. Objects like these present an unusual challenge for collections managers. They were accessioned as scientific representations, but their value has shifted over the last century to the realm of art and history. While these models are undoubtedly important, they are probably no longer useful at many of the institutions that hold them. As such, the Gilmore models exemplify that museum collections are not necessarily static, but change in meaning as the years go by.

If you work at an institution that has one or more Gilmore models in its collection, feel free to leave a comment. I’d love to start a working database of where copies of these models have ended up!

References

Gilmore, C.W. (1939). “A Mounted Skeleton of Dimetrodon gigas in the United States National Museum, with Notes on the Skeletal Anatomy.” Proceedings of the US National Museum 56:2300:525-539.

Gilmore, C.W. (1932) “On a newly mounted skeleton of Diplodocus in the United States National Museum.” Proceedings of the United States National Museum 81:1-21.

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Filed under collections, dinosaurs, history of science, NMNH, paleoart, reptiles

Fossil mounts in the museum environment

Sue and Stan reconstructions from Scott Hartman's DeviantArt page.

Sue and Stan reconstructions from Scott Hartman’s DeviantArt page.

Scott Hartman posted the above image to his DeviantArt page the other day, comparing the Tyrannosaurus specimens Sue and Stan side by side. For those unfamiliar, Hartman is known for his rigorously measured skeletal diagrams of dinosaurs (and sometimes other animals) that are crucial references for many artists and paleontologists. I’m always impressed by Hartman’s work, but this new comparative image really floored me. I knew that Sue is the largest and most complete rex yet found, but I had never properly appreciated what a monster she is. I’ve seen the mounted Sue skeleton at the Field Museum several times, and I’ve seen at least four casts of Stan in various locations, but I never realized what a significant size disparity exists between the two.

Tyrannosaurus Sue at the Field Museum of Natural History.

Tyrannosaurus Sue at the Field Museum of Natural History.

Tyrannosaurus Stan at the National Museum of Natural History.

Tyrannosaurus Stan at the National Museum of Natural History.

It’s not a groundbreaking discovery by any means, but I’m struck by how important the museum environment is when exhibiting a mounted skeleton. I mentioned yesterday that exhibits are never neutral, and this is a particularly clear example. Sue is exhibited in the gigantic central hall of the Field Museum, and in this open, grandiose environment, her size is actually deemphasized. By comparison, the presence of the Stan mount at the National Museum of Natural History was not anticipated during the 1981 renovation of the dinosaur hall (it was added in 2001, I believe) and is sort of crammed into a corner. In the cramped space, Stan looks pretty big, and it’s little wonder I had never appreciated the marked difference in size between the two mounts.

The takeaway, I guess, is that it would do us well to pay careful attention to the design choices (or constraints) in a museum exhibit. We’d like to think that a rare and important specimen like a Tyrannosaurus skeleton speaks for itself, but visitor impressions of even these fossils are shaped by the context they are placed in.

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