SLAC-PUB-7829 September 1998 Stanford Paleoparadoxia Fossil Skeleton Mounting Adele I. Panofsky Stanford Linear Accelerator Center, Stanford University, Stanford, CA 94309 Work supported by Department of Energy DE-AC03-76SF00515. Table of Contents Table of Contents iii Acknowledgments v Stanford Paleoparadoxia 3 Introduction 3 Discussion 7 Restoration of the Missing Parts 8 The Mock-up, Temporary Mounting 14 The Permanent Mounting 24 Front Limbs 25 Rear Limbs 39 The Pelvic Girdle 44 Pinning 48 Central Support Beam 52 Rib Cage 59 The Tail 75 Final Assembly 76 The Head: Skull and Mandible 79 The Hyoid Arch 89 The Hanging Test 92 Painting 92 Teeth 95 Discussion 114 Final Choices for Cheek Teeth Restoration 116 The Snagging Tooth, Canine Tusks, and Incisors 121 Moving and Final Assembly 130 Weight Chart — Paleoparadoxia Casts 133 Modifications Made on the Cast Restorations 139 References 143 iii Acknowledgments During the quarter of a century that it took me to complete this Paleoparadoxia skeleton display for SLAC, I received instruction, encouragement, strong-arm help, advice, and a great deal of friendship from countless people, to all of whom I am enormously grateful. They are too numerous to be mentioned here by name, other than a very few. My hearty thanks to those that must remain anonymous are no less sincere. I especially want to thank Charles Repenning for all the instruction and assistance he gave me from beginning to end, including the use of lab space and equipment at USGS, Menlo Park Division, for the preparation of the Paleoparadoxia skull from Santa Barbara; and for his many visits to SLAC to help me position the skeleton. My thanks also go to all the helpful people at the Museum of Paleontology of the University of California at Berkeley, starting with Dr. Joe Gregory and Dr. Donald Savage, who agreed to accept the Stanford Paleoparadoxia specimen for the University of California museum collections in exchange for plaster casts, and the many others that were ever hospitable during my frequent appearances there. Especially helpful were those individuals entrusted with the care of the collections, Howard Hutchinson, Mark Goodwin, and later Pat Holroyd. Clayton Ray and others of the vertebrate paleontology staff at the National Museum of Natural History, Smithsonian Institution, Washington, D.C., were always hospitable during my several visits. I profited a great deal from discussions with him and his colleagues at the museum, and by having access to the rich collections there. Several sessions that included Daryl Domning of Howard University regarding the dentitions of Paleoparadoxia and other desmostylians were particularly informative. C. Ray also introduced me to the preparator staff and the large, well-equipped preparation labs where the elegant fossil skeleton displays are created. I will be forever grateful for all of the information I received during those visits. Over the years, I had opportunities to visit a number of other natural history museums where I was invariably welcomed, shown the collections and prep labs, and given many tips and suggestions on mounting of skeletons. Among these museums were Princeton University, where Don Baird was most hospitable, showed me around, and introduced me to Barbara Smith Grandstaff and John Horner, and I saw a roomful of the first baby dinosaur specimens. In Salt Lake City, I was given a complete tour of the ongoing work of casting and mounting the fine Allosaurus dinosaur specimens from the Cleaveland-Loydd Quarry by Jim Madsen, and many useful pointers. Other people and places I would like to mention are Yoshikazu Hasegawa at the National Science Museum in Tokyo, Japan; Malcolm McKenna at the American Museum of Natural History, New York City; John Bolt and Oroville Gilpin at the Field Museum in Chicago; and Meemann Chang at the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing, China. I clearly remember spending one informative day, many years ago, in the top floor preparation rooms at the Los Angeles County Museum, Los Angeles, California. Leonard Bessom explained in great detail how he mounted a beautiful La Brea horse skeleton in a rearing position. I gleaned many pages of notes and instructions on skeleton mounting. Thus, my thanks go to him, and also to Larry Barnes, Sam McLeod, and others of the Vertebrate Paleontology Section there, who v extended their hospitality to me on several occasions, and provided important information and access to the collections. Frank Perry, paleontologist at the Santa Cruz City Museum of Natural History, also receives my sincere gratitude for sharing the rich accumulation of Paleoparadoxia teeth gathered at that museum, and for introducing me to amateur collectors, Steve Kunkle and Stan Jarocki, who also made their specimens available to me. I am equally grateful to Mike Long, another amateur collector in Santa Cruz, who provided a very important incisor tooth. Here at Stanford University, I have formed a rewarding friendship with Judy Terry Smith and her husband, Jim Smith. Judy has followed the progress of our Paleoparadoxia mounting project over the years, providing interest and encouragement. Being an invertebrate paleontologist, she helped me choose from the numerous invertebrate fossils also found at SLAC for inclusion in the Paleoparadoxia display. I am most grateful for her identification and dating of these specimens. As the skeleton is created from plaster casts, the genuine fossils scattered on the sandy floor of the display add realism to the scene. At SLAC, hundreds of people have given their assistance, out of friendship and interest in this intriguing mechanical project. I am grateful for their every suggestion and effort. Most especially, I thank Richard Jones of Plant Engineering for his dedication to the successful completion of the display and continued interest in its upkeep. John Flynn has my deepest gratitude for his ever-cheerful assistance and innovative design and fabrication of so much of the skeleton support system. A great many others at SLAC also contributed to the success of this project, including the past and present Directors of the Laboratory and their assistants. Members of my family, children and grandchildren, helped in various important ways. Not only did my granddaughter, Catherine Panofsky, assist with some important steps in the mounting, she is the artist who painted the fine undersea mural on the back wall of the display. To all of these dear ones, and to my ever-so-patient husband, I extend my most sincere appreciation. The final effort has been the production of this report. I deeply appreciate the corrections and suggestions given by my two reviewers, Charles Repenning and my son, Richard Panofsky. The report was made ready for printing by Maria Breaux, and the illustrations were prepared by Terry Anderson, in conjunction with the staff of the SLAC Technical Publications Department. Thank you one and all! Adele Panofsky May 1, 1998 vi 1 Stanford Paleoparadoxia Introduction On October 2, 1964, the astonishingly well-preserved fossil skeleton of the desmostylian genus, Paleoparadoxia, was discovered in the original excavations for the two-mile long linear accelerator at Stanford University. The fossil was almost entirely articulated and nearly complete. It is usually referred to as the “Stanford Paleoparadoxia.” The bulldozers had cut away the sandstone by 8 or 10 feet of horizontal distance more than the original plan specified. Without this error the fossil would not have been discovered, and because of it, extra space had been provided so it was possible to remove the specimen without causing any loss of time on the accelerator construction project. The first vertebrate paleontologist to see the exposed fossil was Earl L. Packard, Research Associate at Stanford University and Emeritus Professor from Oregon State University. He advised excavating the fossil because it appeared to be excellently preserved and possibly very interesting, as proved correct. Dr. Packard soon arranged to have the fossil excavation supervised by Charles A. Repenning, vertebrate paleontologist and marine mammal specialist, Menlo Park center of the U.S. Geological Survey. Dr. Repenning expressed immediate interest and took charge of the collection of the skeleton at SLAC and its removal to the paleo lab at the USGS for preparation, doing much of the work himself. Besides himself and Dr. Packard, several volunteers gave their time, among them Ray Cox, graduate student in the Stanford Geology Department and the author, Adele Panofsky. It took five weeks to complete the excavation. Table 1 lists all the skeletal elements that were preserved and collected at the site. The specimen had been buried lying on its back on the sand of the sea floor. The ribs had fallen to the sides before burial and at least two dozen isolated shark teeth were found in the skeleton or very near to it. Bulldozing to make the discovery cut had removed the right shoulder joint and any vertebrae and other elements anterior to the second thoracic that might have been present, except for the left side of the lower jaw that was recovered under the ribs. From the standpoint of identification, this left half mandible was the most important element, identifiable as the rare herbivorous marine mammal Paleoparadoxia, by comparison with the only known North American specimen at that time, UCMP 40862, a right lower jaw published by Roy H. Reinhart, 1960.1 The SLAC sediments had previously been recognized as of marine origin, containing other fragmentary marine mammal fossils from whales, porpoises, and sea lions, and also various marine invertebrates and sharks’ teeth.2 Dr. Packard and Dr. Repenning made some preliminary studies, particularly of the nearly complete fore and rear limbs. They noted some interesting adaptations for locomotion both in and out of water, and some well-preserved pathological conditions of some bones, indicating the probable cause of death of that individual animal.