We are wrapping up the removal of specimens from the Fossil Halls at the National Museum of Natural History, the first step in our massive renovation project. During the last few weeks, riggers carefully brought large fossils mounted high up on the walls back down to Earth. One of the skeletons, shown below, was from a Late Cretaceous predatory dinosaur, Gorgosaurus libratus (USNM 12814).
The photo on the left shows the mounted Gorgosaurus being lowered from its high perch. To bring it down safely, the riggers strapped the slab into a steel cradle, attached the cradle to cables strung from I-beams in the roof, and used hoists to control its descent. The skeleton (shown safely on the ground in the photo on the right) is mounted in a “death pose” with the bones arranged as if still in the ground. For many years this specimen was labeled Albertosaurus libratus because Gorgosaurus was once thought to belong to that genus. Click photos to zoom.
This fine specimen was collected in 1913 in Alberta, Canada, by Barnum Brown, a paleontologist at the American Museum of Natural History (AMNH) in New York, and came to the Smithsonian in 1933 as part of a complicated exchange of fossils. (Natural history museums have long traded “duplicate” specimens as a way of broadening their collections and fleshing out their exhibits - an earlier post on this blog describes the 1935 exchange with the Carnegie Museum of Natural History that netted the Smithsonian its Camarasaurus.) The trade for the Gorgosaurus had its root in an attempt by the Smithsonian, in 1919, to obtain a specimen of Moropus elatus, a large herbivore that lived during the Early Miocene. The AMNH had collected enormous numbers of bones of Moropus during a decade of work at Agate Springs Ranch (now Agate Fossil Beds National Monument) in Kansas, and it was offering several exhibit-quality skeletons for sale.
This vintage photo shows a mounted skeleton of Moropus, with its characteristic long front legs and clawed toes. The Smithsonian had no specimen of this horse-sized animal, but hoped to get one in a fossil exchange with the American Museum of Natural History. Click for image source.
Having neither the cash in hand nor the hope of raising the necessary funds, James W. Gidley, of the Smithsonian’s NMNH, suggested that the skulls and jaws of several species of brontothere - another large herbivore - might serve as an even trade. AMNH researcher (and President) Henry Fairfield Osborn badly wanted several of our brontothere specimens for study and display, and Gidley had selected some excellent skulls for him.
In this 1919 photo, NMNH Assistant Curator James W. Gidley (right), and two fossil preparators stand in the preparation lab with the newly mounted skeleton of a brontothere, Brontotherium hatcheri (USNM 4262), which was placed on display here in 1920.
These photos show part of an NMNH exhibit comparing the skulls and jaws of 22 different species of brontothere. The AMNH hoped to create a similar display, but needed more specimens. Thanks to vigorous collecting in the 1880s and 1890s by John Bell Hatcher, we possessed a superabundance of brontotheres, and could offer some in trade.
The brontotheres were sent to Osborn, but Walter Granger of the AMNH informed Gidley that a skeleton of Moropus could not be sent in exchange. He wrote that any deal for Moropus must be cash only. Not only did the AMNH need to pay the landowner on whose property it had been quarrying, but it wanted to recover the cost of shipping and preparing its “duplicate” specimens. Granger applied some not-so-subtle pressure in his argument for cash, writing that the finest skeleton had been sold already to the Yale Peabody Museum of Natural History, and others had been offered for sale to two European museums. "The chances of securing new skeletons of Moropus are remote," he wrote. "There are undoubtedly more of them in the hill from which ours … came, but the cost of removing them has now become almost prohibitive because of the overburden.” (Overburden is the overlying rock matrix that must be dug through to reach a fossil-bearing layer). Gidley offered additional specimens in hopes of making an exchange more attractive, but the AMNH held firm, saying that at least some cash needed to change hands. Frustrated, Gidley wrote to AMNH curator William D. Matthew, saying, “I hope your rejection of my proposition does not mean that the deal is entirely closed, but only that it may be approached from a somewhat different angle.“
An acceptable angle wasn’t found until 1932, when the AMNH wanted to include a long-necked giant sauropod, Barosaurus, in a new exhibit on dinosaurs. The AMNH didn’t own a Barosaurus, and was ready to deal. The skeleton it hoped to acquire had been excavated from Dinosaur National Monument (the source of many sauropod skeletons) by three separate institutions working in the same quarry in successive years; some of the specimen was at the Carnegie Museum of Natural History, some was at the University of Utah, and the rest was at NMNH.
NMNH Curator Charles W. Gilmore had acquired our portion (USNM 11657) in 1924, while excavating a Diplodocus to exhibit in the Fossil Halls. The skeleton was incomplete, so Gilmore selected bones from a nearby skeleton, thought to be another Diplodocus, to fill in the gaps. When the supplemental bones turned out to be from a Barosaurus, instead, they were placed in our collections. In 1923 Osborn, of the AMNH, was tasked with trading for them. He offered the skeleton of Gorgosaurus (AMNH 5428,) or, if we preferred, a ceratopsian dinosaur. In January of 1933, he sweetened the deal, adding to the offer (finally!) a mountable skeleton of Moropus. In very short order, the Smithsonian's part of the Barosaurus was loaded into thirteen boxes and sent to New York by truck, and the Gorgosaurus and Moropus were sent in return. And what happened to the brontothere skulls sent to the AMNH fourteen years earlier? They became part of this deal, too. The AMNH got to keep them.
The skeleton of Moropus (NMNH 12816) (right) was mounted for display and installed in the Fossil Halls around 1936. Before the recent renovation work began, it was exhibited in front of a mural showing life reconstructions of many species excavated from the Agate Fossil Beds. The mural was painted by Jay Matternes in 1961 and includes two adults and a juvenile Moropus, shown in the detail on the left.