Browsing by Author "Tschopp, Emanuel"
Now showing 1 - 4 of 4
Results Per Page
Sort Options
Item Complex overlapping joints between facial bones allowing limited anterior sliding movements of the snout in diplodocid sauropods. (American Museum novitates, no. 3911)(American Museum of Natural History., 2018-10-25) Tschopp, Emanuel; Mateus, Octávio; Norell, Mark.Diplodocid sauropods had a unique skull morphology, with posteriorly retracted nares, an elongated snout, and anteriorly restricted, peglike teeth. Because of the lack of extant analogs in skull structure and tooth morphology, understanding their feeding strategy and diet has been difficult. Furthermore, the general rarity of sauropod skulls and the fragility of their facial elements resulted in a restricted knowledge of cranial anatomy, in particular regarding the internal surface of the facial skull. Here, we describe in detail a well-preserved diplodocid skull visible in medial view. Diagnostic features recognized in other skulls observable in lateral view, such as the extended contribution of the jugal to the antorbital fenestra, are obliterated in medial view due to extensive overlapping joints between the maxilla, jugal, quadratojugal, and the lacrimal. These overlapping joints permitted limited anterior sliding movement of the snout, which likely served as a kind of "shock-absorbing" mechanism during feeding. Diplodocid skulls therefore seem to have evolved to alleviate stresses inflicted on the snout during backward movements of the head, as would be expected during branch-stripping or raking.Item Reconstructing the specimens and history of Howe Quarry (Upper Jurassic Morrison Formation; Wyoming). (American Museum novitates, no. 3956)(American Museum of Natural History., 2020-06-24) Tschopp, Emanuel; Mehling, Carl; Norell, MarkIn 1934, Barnum Brown of the American Museum of Natural History in New York (AMNH) led a large-scale dinosaur excavation in northern Wyoming, where he had found bones two years earlier. Initially, Brown expected to excavate two skeletons of sauropod dinosaurs, but soon after opening the quarry, the team realized that the site far exceeded their expectations: in the end, they unearthed approximately 3000 bones within six months and sent approximately 144 crates back to the AMNH. Due to the enormous number of bones, the site became world famous as a dinosaur graveyard, and media from all over the United States and abroad reported on the expedition. Soon after, however, the collection shifted away from a curatorial focus. What followed was a history of neglect: inappropriate storage conditions, water and fire damage, collapsing wooden boxes, and deteriorating plaster jackets. Relocation and further excavation of the quarry by the Sauriermuseum Aathal (Switzerland; SMA) from 1989 to 1991 confirmed earlier finds of skin impressions and resulted in the recognition of a novel diplodocid sauropod: Kaatedocus siberi. Given that the amount of bones found by the AMNH far exceeded those found by the SMA, a new project was started in 2017 to reassess the state and scientific value of the historic collections at AMNH. Although most of the bones are heavily fragmented, preliminary results show that overall preservation is still exceptional. Here, we reconstruct the history of the excavation, as well as past conservation and preparation procedures, and provide a report of current efforts to prepare, conserve, and catalog the material that has remained in storage since the 1930s. These current efforts show that historic collections, even after decades of neglect, can be of great and unexpected value, both for research and scientific outreach.Item Supplemental Material for 'Reassessment of a historical collection of sauropod dinosaurs from the northern Morrison Formation of Wyoming, with implications for sauropod biogeography. (Bulletin of the American Museum of Natural History, no. 437)'(2019-11) Tschopp, Emanuel; Maidment, Susannah C.R.; Lamanna, Matthew C.; Norell, Mark A.Supplemental Material for 'Reassessment of a historical collection of sauropod dinosaurs from the northern Morrison Formation of Wyoming, with implications for sauropod biogeography. (Bulletin of the American Museum of Natural History, no. 437)'Item Supplemental Material for 'Reconstructing the specimens and history of Howe Quarry (Upper Jurassic Morrison Formation; Wyoming). (American Museum novitates, no. 3956)'(2020-06-24) Tschopp, Emanuel; Mehling, Carl; Norell, MarkSupplemental Material for 'Reconstructing the specimens and history of Howe Quarry (Upper Jurassic Morrison Formation; Wyoming). (American Museum novitates, no. 3956)'