Category Archives: thyreophorans

One Year to Deep Time

When the fossil halls at the National Museum of Natural History closed for renovation in 2014, five years seemed like an interminable amount of time to wait for the reopening. But the NMNH crew has been hard at work, and suddenly the June 2019 debut of the new National Fossil Hall is almost in sight. I’ve mostly avoided reporting on each and every bit of information pertaining to the new exhibit, but as we approach the one-year-to-opening milestone the drip is likely to become a deluge. That means that this is probably a good time to do a round-up of everything that has been officially revealed about the new exhibit up to this point.

The East Wing Restored

The original architectural grandeur is back. Images from of the Smithsonian Institution Archives and the Washington Post.

The building that is now NMNH opened in 1910. Its granite-heavy, Beaux Arts construction was a departure from the Victorian style of the first United States National Museum, but it looked right at home with the other federal buildings around the National Mall. As originally designed, the building resembled a squat “T” from above, with three large wings (facing east, north, and west) extending from a central rotunda. The east wing — a vast space with bay windows, intricate plaster detailing, and a skylight three stories up — has always housed fossil displays. Over the course of the 20th century, however, the once spacious hall was repeatedly carved into smaller sections. Windows and architectural flourishes were covered up, and by the time the last round of renovations was completed in 1985 the east wing had become cramped and gloomy.

A major part of the current renovation has been returning the space to its original glory. Grunley Construction spent two years restoring and recreating the east wing’s 1910 architecture, as well as updating infrastructure and improving the space’s energy efficiency. Most of this process was visible via webcam. Last November, the Washington Post provided some stunning floor-level photos of the restored hall. Wide open and filled with natural light, the renovated hall is glorious to behold, even without the fossils.

A Story of Environmental Change

Many exhibits and books about paleontology portray the evolution of life as though it occurred in a vacuum. In fact, the evolution of animals and plants is primarily driven by environmental upheaval — changing climate, shifting geography, and so forth. Sometimes this relationship goes the other way, and keystone organisms (such as grass in the Neogene or humans in the present day) drastically change the world around them. Environmental change over time is at the heart of the National Fossil Hall’s story. It’s worth quoting the official theme statement in full:

Visitors to the Museum will be able to explore how life, environments, and ecosystems have interacted to form and change our planet over billions of years. By discovering and harnessing the tools and methods paleobiologists use to study fossils, visitors will gain a deeper understanding of how the world works.

The distant past affects all of us today and will continue to do so in the future. How will climate change impact the natural world and our daily lives? How can we make informed choices about our ecosystems as individuals and as a species? How can we all become informed citizens of a changing planet?

These themes are reflected by the physical layout of the exhibit, which is chronological but not strictly proportional. Specimens are clustered onto islands situated throughout the open floorplan, each representing North America at a particular point in time. While anchored by a few charismatic mounts, the islands also include all manner of small animals, invertebrates, and plants that were part of that environment. In this way, each island shows a complete ecosystem that existed at a particular time. Moving among these displays, visitors should get a sense of how phenomena like climate change and faunal interchange can completely transform an ecosystem over millions of years.

During the development process, curators and exhibit specialists agreed that the hall should not be an encyclopedia of past life. Instead, everything ties back to main story. Big, showy specimens like dinosaurs are contextualized as products of environmental change. Meanwhile, fossils that visitors might otherwise overlook but are critical to our understanding of ecological change over time, like pollen grains or leaves, are literally and figuratively pedestaled to emphasize their importance.

The Nation’s T. rex

The Nation’s T. rex, temporarily assembled in the Research Casting International workshop. Image by Great Big Story.

The centerpiece of the National Fossil Hall is a real Tyrannosaurus rex skeleton — the first real T. rex (as opposed to a cast) the Smithsonian has ever displayed. The specimen in question has been known as the “Wankel Rex” since it was discovered by avocational fossil hunter Kathy Wankel in 1988. It has been held in trust at Bozeman, Montana’s Museum of the Rockies, but since it came from Army Corps of Engineers land it is technically owned by the U.S. federal government. Although several casts of the Wankel Rex are on display around the world, the original fossils have never before been assembled into a standing mount. That’s changing now that the fossils have been transferred to the Smithsonian.

Curator Matt Carrano designed a deliriously cool pose, with the Tyrannosaurus poised as though prying the head off of a prone Triceratops. NMNH is visited by eight million people every year, so the Wankel Rex (now the Nation’s T. rex) will soon be the most viewed T. rex skeleton in the world. The Nation’s T. rex story has been covered by the Washington Post, NPR, National Geographic, and Smithsonian Magazine, among many others.

Poses that Show Behavior

The remounted mammoth demonstrates plausible behavior. Left image by the author, right image from Smithsonian Magazine.

Historically, mounted fossil skeletons were most often given anatomically neutral poses. This was a structural engineering necessity as much as it was a curatorial preference. However, modern technology has made it possible to safely display casts and even real skeletons in surprisingly dynamic poses. At many museums, this has usually manifested as mounted skeletons fighting or simply roaring at each other. In contrast, the NMNH team has endeavored to create dynamic mounts that show a greater variety of interesting behavior evidenced by the fossil record. For example, the remounted mammoth (shared during a talk by NMNH Director Kirk Johnson) is pushing its tusks along the ground, as if clearing snow off the grass. The Allosaurus (headless in the right image) is crouching next to a nest mound. Even the aforementioned T. rex and Triceratops scene is inspired by real research into T. rex feeding mechanics.

The Anthropocene

Most exhibits about the history of life close at some point in the past, but the National Fossil Hall continues the story into the present day. We are in the midst of an extinction event of our own making, and anthropogenic climate change, habitat destruction, and invasive species are as dangerous as any asteroid. During our very limited time on Earth, humans have altered the climate, the rate of erosion, and the acidity of oceans. Whether or not you think adopting “Anthropocene” as a formal geologic unit is reasonable, we have inarguably changed the planet in geologically measurable ways.

Curator Scott Wing discussed his approach to interpreting the age of humans in a Geological Society of America talk and in an Earth Matters blog post. The key is to make it clear that in spite of our destructive potential, humans have the power to mitigate and manage the consequences of altering the world around us. The exhibit will show visitors how they can take responsibility for humanity’s collective legacy.

Marsh Dinosaurs Re-imagined

An updated Stegosaurus replaces the 2004 cast, which replaced the original 1913 mount. Images from the Smithsonian Institution Archives and Kirk Johnson on twitter.

The new Edmontosaurus cast replaces the original mount, which had gone unmodified since 1904. Images by NMNH Paleobiology and Will S.

Most of the dinosaur skeletons exhibited at NMNH were assembled before 1920. Originally excavated by O.C. Marsh’s crews in the 19th century, these specimens have gone on to lead second lives on display, and have been seen by generations of visitors. Nevertheless, time has taken its toll. Some mounts have been rendered out-of-date by new discoveries, while others have gradually deteriorated due to fluctuating temperature and humidity, not to mention constant vibration from passing crowds. Before the fossil halls closed in 2014, NMNH preparators had already dismantled three historic dinosaurs (Triceratops, Stegosaurus, and Camptosaurus) and replaced them with updated casts. Returning these fossils to the collections ensures their continued safety, while also giving paleontologists a chance to study them for the first time in decades.

The renovation has been an opportunity to give other at-risk specimens the same treatment. It was especially important to get the real Ceratosaurus, Edmontosaurus, and Thescelosaurus skeletons off the exhibit floor because these are all holotypes — the original specimens that were used to define the species. Set in plaster on the exhibit walls, these important skeletons were virtually inaccessible. And as the preparators discovered when they removed them, they had not even been fully extracted from the rock they were found in. The real fossils are now available for research, while casts with lively poses and up-to-date anatomy will take their place on display (before anyone panics, the new exhibit will still feature several real dinosaur skeletons).

The Pocahontas Mine

As reported by the Bluefield Daily Telegraph, a Smithsonian crew of paleobotanists, geologists, and exhibits specialists visited the historic Pocahontas Exhibition Mine last November. This coal mine near Pocahontas, Virginia operated from 1882 to 1938, when ceased production and became a tourist attraction. The Smithsonian crew took photographs, video, and silicon molds of the mine’s walls, which are covered with Carboniferous-era plant impressions. A reconstruction of the fossiliferous mine will anchor the Carboniferous section of the exhibit.

Treasures from the Collection

A near-perfect Ophiacodon from Texas. Photo via the NMNH Department of Paleobiology.

A typical natural history museum has less than one percent of its collection on display at any time, and NMNH is no exception. In addition to introducing brand-new specimens and updating old ones, the renovation is an opportunity to bring a variety of never-before-displayed objects from the collections to the display floor. Of the hundreds of specimens earmarked for display, I can only highlight a few.  There’s the historic cast of the plesiosaur Rhomaleosaurus, which has been in the collection since 1895 but never displayed. There’s the skull of the tusked whale Odobenocetops, which preparator Michelle Pinsdorf profiled in a webcast last year. Carrano showed NPR’s Adam Cole a sauropod osteoderm, collected decades ago but only identified recently. And then there’s the near-perfect Ophiacodon pictured above, collected in 1988 by Arnie Lewis and Nicholas Hotton. I remember this guy from my intern days, when it was referred to as “sleeping beauty.”

Research Casting International will start installing the large skeletons this summer, and then the countdown to opening day begins in earnest. Here’s wishing the NMNH team all the best as their years of work finally comes to fruition!

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Filed under dinosaurs, exhibits, Extinct Monsters, fossil mounts, mammals, museums, NMNH, ornithopods, theropods, thyreophorans

Denver’s Fighting Dinosaurs

Allosaurus and Stegosaurus mount

Allosaurus and Stegosaurus mounts at the Denver Museum of Nature and Science. Source

Just a quick post today to keep the blog moving. The Allosaurus and Stegosaurus skeletons at the Denver Museum of Nature and Science are among my all-time favorite fossil mounts. While there is no shortage of fighting dinosaur displays today, these mounts were something of a novelty when they were unveiled in 1995 as the centerpieces of the trendsetting “Prehistoric Journey” exhibition. A far cry from the stiff, macabre trophies that had dominated paleontology exhibits since the beginning of the 20th century, the Allosaurus and Stegosaurus plainly represent swift and active animals. Unlike many similar scenes, however, the action here is tempered with careful attention to anatomical detail: no limbs are hyperextended, and no bones are out of place.

The Stegosaurus

A postcard showing STegosaurus in the 50s

This postcard shows the original Stegosaurus mount around 1950.

High school teacher Frank Kessler discovered the Stegosaurus (DMNH 1483) in 1937 while leading a nature hike north of Cañon City. While the Garden Park region had been known for its Jurassic dinosaur fossils since the days of O.C. Marsh and E.D. Cope, Kessler’s find was in a previously unexplored area. Kessler contacted the Denver Museum of Natural History (now the DMNS), and Robert Landberg was dispatched to lead a thorough excavation. Landberg eventually recovered a 70% intact Stegosaurus, in addition to a multitude of turtles, crocodiles, and isolated dinosaur bones.

Back in Denver, Phillip Reinheimer assembled the Stegosaurus fossils into a standing mount. A former steelworker from Pittsburgh, Reinheimer was initially hired by the museum to maintain the furnaces, but eventually proved to be an uncommonly talented fossil preparator. Described by Johnson and Stucky as “a master craftsman,” Reinheimer remains something of a legend among preparators to this day. Reinheimer completed the Stegosaurus mount in 1938, and it remained a focal point of the museum’s fossil exhibits for decades afterward. In 1982, this specific specimen was named the state fossil of Colorado.

The Allosaurus

A close up of Allosaurus

Another look at Allosaurus and Stegosaurus. Source

In 1979, 13 year-old India Wood discovered and identified an Allosaurus skeleton on her family’s ranch in Moffat County, Colorado. She excavated the find herself over a period of three years, until her mother encouraged her to reach out to the DMNS. After seeing the fossils Wood had been collecting in a box under her bed, paleontology curator K. Don Lindsay agreed to excavate the rest of the skeleton.

The project took two more summers to complete, and Wood remained an active participant. Although many at the museum remember being impressed by her knowledge and talent, Wood ultimately did not pursue paleontology as a career – she instead went on to earn an MBA from MIT and founded a business consulting firm. Meanwhile, Wood’s Allosaurus (DMNH 2149) remained in storage for more than a decade – until it was selected to feature in an ambitious new exhibit.

Prehistoric Journey

From left to right

From left to right: Wood’s Allosaurus, Karen Alf, Bryan Small, Jon Christians, Jerry Harris, Jennifer Moerman, Ken Carpenter, and Kessler’s Stegosaurus. Image from Johnson and Stucky 2013.

The DMNS had been a powerhouse of paleontology research in the early and mid 20th century, but by the 1980s its reputation had slipped away. That changed in 1989 when Richard Stucky came on board as the new Curator of Vertebrate Paleontology. Stucky brought order to the museum’s historic collections, and laid out plans for a comprehensive new exhibit entitled “Prehistoric Journey.” He also hired a new pool of talent to make the project happen, including paleontologist and preparator Ken Carpenter. As Chief Preparator, Carpenter was tasked with moving, restoring, and in some cases remaking the classic Reinheimer mounts, including the Kessler Stegosaurus. The DMNS crew also ventured into the field to collect new material for Prehistoric Journey. Among the most impressive finds was a new Stegosaurus (DMNH 2818), discovered by Bryan Small at Garden Park only a few hundred yards from where the Kessler specimen was unearthed. This articulated specimen clarified for the first time the position of the animal’s plates and spikes, and also confirmed that Stegosaurus had throat armor made up of tiny hexagonal ossicles. All of this informed the remounting of the Kessler Stegosaurus.

Carpenter’s take on this classic specimen paired it with India Wood’s Allosaurus, right in the middle of the Prehistoric Journey dinosaur gallery. The Stegosaurus is shown defending two (largely reconstructed) juveniles from the attacking theropod, while five or six Othnielia (casts) flee the scene. Twenty years after its 1995 debut, this scene is still among the most impressive fossil mounts around because of the seemingly effortless way it captures action and behavior. Carpenter and his colleagues did not only restore the shape of these animals but breathed life into them. The viewer cannot help but imagine the events that preceded this encounter, as well as the eventual outcome. The suspended bones are like brush strokes in an impressionist painting, swooping through the space and imbuing it with energy and motion. The fact that these are mostly original fossils rather than lightweight casts makes the display all the more impressive. I’ve said it many times before, but it bears repeating that fossil mounts are fascinating, challenging objects in that they are both authentic specimens and interpretive creations. In many cases these conflicting identities are jarring. However, with the right amounts of artistry, aptitude, and solid science, a fossil mount can transcend this juxtaposition and serve each identity equally well. Not an easy feat, but the DMNS Stegosaurus and Allosaurus are a defining example of the craft.

References

Carpenter, K. (1998). Armor of Stegosaurus stenops and the Taphonomic History of a New Specimen from Garden Park, Colorado. Modern Geology Vol. 22: pp. 127-144.

Johnson, K.R. and Stucky, R.K. (1995). Prehistoric Journey: A History of Life on Earth. Golden, CO: Fulcrum Publishing.

Johnson, K.R. and Stucky, R.K. (2013). Paleontology: Discovering the Ancient History of the American West. Denver Museum of Nature and Science Annals No. 4: pp. 231-282..

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Filed under dinosaurs, DMNS, fossil mounts, museums, theropods, thyreophorans

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

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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Extinct Monsters: The Marsh Dinosaurs, Part II

Read the Marsh Dinosaurs, Part I or start the Extinct Monsters series from the beginning.

During the first decade of the 20th century, the United States National Museum paleontology department was located in an offsite building in northwest Washington, DC. It was here that preparators Charles Gilmore, Norman Boss, and James Gidley slowly but surely worked through the literal trainloads of fossil specimens O.C. Marsh had acquired for the United States Geological Survey. The Marsh Collection included unknown thousands of specimens, many of them holotypes, and there was no shortage of gorgeous display-caliber material. Even after the “condemnation of worthless material” Gilmore and his team quickly filled the available exhibit space in the Arts and Industries Building with mounted skeletons.

The Ceratosaurus

With no more display space and plenty more fossils, it was fortunate that the USNM moved to a new, larger building in 1910. In this iconic, green-domed building (now the National Museum of Natural History), the paleontology department received newly furnished collections spaces and the entire east wing to fill with display specimens. The evocatively titled Hall of Extinct Monsters provided a new home for the mounted skeletons already constructed for the old exhibit, as well as plenty of room for new displays.

The Ceratosaurus nasicornis holotype was originally housed in a glass case. Image courtesy of the Linda Hall Library.

Ceratosaurus. Photo by the author.

The delicate arms of Ceratosaurus were removed several years prior to the hall’s closing. Photo by the author.

One of the first new additions was the type specimen of Ceratosaurus nasicornis (USNM 4735), mounted in relief. Marshall Felch led the excavation of this specimen in 1883 at a quarry near Cañon City, Colorado. The nearly complete skeleton received a cursory description from Marsh upon its discovery, but it was Gilmore who described it properly in 1920, ten years after it was put on display. When it was introduced to the Hall of Extinct Monsters, this was the only Ceratosaurus specimen yet found, making the mount a USNM exclusive. The skeleton was originally displayed in a glass case, but during the 1963 renovation it was placed in a more open setting.

Even today, Ceratosaurus is only known from a handful of specimens. For this reason, the original Ceratosaurus fossils will not be returning when the current renovation is completed in 2019. The new hall will instead feature a three-dimensional, standing cast of this skeleton. The original fossils are now in the museum’s collections, available for proper study for the first time in over a century.

The Camptosaurus

In 1912, two mounted skeletons of Camptosaurus, one large (USNM 4282) and one small (USNM 2210), were introduced to the Hall of Extinct Monsters. William Read excavated both specimens at Quarry 13 in the Como region of Wyoming a quarter of a century earlier. Representing the first-ever mounted skeletons of Camptosaurus, these specimens have had a rather complex taxonomical history. Marsh initially described both specimens as Camptosaurus nanus, a new species within the genus Camptosaurus (the type species was Camptosaurus dispar, also coined by Marsh). After the fossils were acquired by the USNM, Gilmore re-described the larger individual as a new species, Camptosaurus browni. This designation remained until the 1980s, when Peter Galton and H.P. Powell determined that C. nanus and C. browni were actually both growth stages of C. dispar.

Regardless of what they are called, both specimens were remarkably well-preserved and reasonably complete. Most of the skeletal elements of the larger Camptosaurus came from a single individual that was found articulated in situ. However, some of the cervical vertebrae came from another specimen from the same quarry, and the skull, pubis, and some of the ribs were reconstructed. Of particular interest is the right ilium, which has been punctured all the way through by a force delivered from above. Gilmore postulated that “the position of the wounds suggest…that this individual was a female who might have received the injuries during copulation.” The smaller “C. nanus” was also found mostly complete, but two metatarsals came from a different individual and the skull and left forelimb were sculpted.

The original pair of Camptosaurus mounts. Image from Backyard Dinosaurs.

Gilmore supervised the creation of both mounts, and constructed the larger individual himself. Norman Boss took the lead on the smaller specimen. As with the other dinosaur skeletons, the mount was centered on an inch-thick steel rod bent to conform to the shape of the vertebral column. Bolts were drilled directly into the vertebrae to attach them to the armature, and the vertebral foramina were filled with liberal amounts of plaster to secure them to the rod. A similar process was used to assemble each of the limbs, and the ribs were supported by a wire cage.

Gilmore aimed to correct many specifics of Marsh’s  original illustrated reconstruction of Camptosaurus. To start, he shortened the presacral region to make a more compact torso. Marsh had also inexplicably illustrated Camptosaurus with lumbar vertebrae (a characteristic exclusive to mammals), which Gilmore corrected. Finally, Marsh had reconstructed the animal as an obligate biped, but Gilmore  determined that “Camptosaurus used the quadrupedal mode of progression more frequently than any other known member of Ornithopoda.” Accordingly, the larger Camptosaurus mount was posed on all fours. The completed Camptosaurus mounts were placed together in a freestanding glass case toward the rear of the Hall of Extinct Monsters. In 1962 the pair was moved to the left of the Diplodocus on the central pedestal of the redesigned exhibit. During the 1981 renovation they were moved a few feet back, so that they were alongside the sauropod’s tail.

This cast replaced the original Camptosaurus mount in 2010. Photo by the author.

This cast replaced the original Camptosaurus mounts in 2010. Photo by the author.

The retired plaster skulls of the original Camptosaurus mounts. Photo by the author.

The retired plaster skulls of the original Camptosaurus mounts. Photo by the author.

Both Camptosaurus skeletons taken off exhibit in 2010 and replaced with a cast of the adult. The delicate fossils, which had suffered from considerable wear and tear over the past hundred years, were stabilized and stored individually for their protection. The new mount has a number of upgrades to reflect our improved understanding of dinosaur anatomy. The arms are closer together and the palms face inward, because the pronated (palms down) hands on Gilmore’s version have been determined to be a physical impossibility. The new mount also features a completely different skull. The rectangular model skull used on the original mount was based on Iguanodon, but new discoveries show that the skull of Camptosaurus was more triangular in shape. Both the adult and juvenile Camptosaurus will appear in the new National Fossil Hall.

The Stegosaurus

The Smithsonian’s first Stegosaurus exhibit was a life-sized model built for the 1904 World’s Fair in St. Louis. This model found its way into the Hall of Extinct Monsters in 1910. In 1913, the model was joined by a mounted Stegosaurus skeleton found at the same Cañon City quarry as the Ceratosaurus. A third Stegosaurus, the holotype of S. stenops, was introduced in 1918. Lovingly called the “roadkill” Stegosaurus, USNM 4934 is remarkable in part because it was found completely articulated. In fact, before its 1886 discovery by Marshall Felch, it was unknown exactly how the animal’s plates were positioned on its back.

Standing Stegosaurus mount and life-size model, circa 1950. Photo courtesy of the Smithsonian Institution Archives.

Stegosaurus

Stegosaurus model, standing mount, and “roadkill” on display in the Hall of Extinct Monsters. Source

All three Stegosaurus displays were moved in 1963 and 1981. In Fossils: The History of Life, the Stegosaurus skeletons were positioned flanking the Diplodocus in the central display area, with the standing mount on the right and the roadkill skeleton on the left. The model Stegosaurus stood opposite the mount. Just like the Triceratops and Camptosaurus, many decades on display took their toll on the standing Stegosaurus, so in 2003 the fossils were removed from the exhibit. Dismantling the Stegosaurus was particularly challenging because of the large amount of plaster applied by the mount’s creators. In some cases the plaster infill had to be removed with hand tools, which put further pressure on the fossils. Additionally, the rod supporting the backbone had been threaded right through each of the vertebrae, and was extremely difficult to remove. A casted Stegosaurus mount in a more active pose was returned to the exhibit in 2004.

Cast of Stegosaurus and Camptosaurus. Photo by the author.

Casts of Stegosaurus and Camptosaurus. Photo by the author.

Roadkill stego

“Roadkill” Stegosaurus in 2014. Photo by the author.

After 110 years on display at the Smithsonian, the model Stegosaurus has been donated to the Museum of the Earth in Ithaca. The roadkill Stegosaurus, however, will feature prominently in the new National Fossil Hall, mounted upright on the wall by the exhibit’s secondary entrance. The 2004 Stegosaurus cast had a number of anatomical issues and will not be returning – instead, it will be replaced by an updated cast made from the same original fossils.

The Marsh dinosaurs have been of critical importance in our understanding of the Mesozoic world, but at this point these fossils are historic artifacts as well. When they were uncovered, the American civil war was still a recent memory, and railroads had only recently extended to the western United States. Before the first world war they had been assembled into mounts, and for more than a century these fossils have been mesmerizing and inspiring millions of visitors. Several of these mounts, including the Triceratops, Ceratosaurus and Camptosaurus, were the first reconstructions of these species to ever appear in the public realm, and therefore defined popular interpretations that have lasted for generations. Some visitors may lament that many of the original specimens have been recently been replaced with replicas, but the fact is that these are irreplaceable and invaluable national treasures. They inform us of our culture, and our dedication to expanding knowledge and our rich natural history. We only get one chance with these fossils, and that is why the absolute best care must be taken to preserve them for future generations.

References

Gilmore, C.W. 1912 “The Mounted Skeletons of Camptosaurus in the United States National Musuem.” Proceedings of the US National Museum 14:1878.

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.

Jabo, S. 2012. Personal communication.

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Filed under collections, dinosaurs, exhibits, Extinct Monsters, field work, fossil mounts, history of science, museums, NMNH, ornithopods, reptiles, theropods, thyreophorans