Guangxi Province of southern China is the last bastion of an extraordinary group of animals known as crocodile lizards. Today, there is only one living member of this group, yet it stretches back to the time of the dinosaurs. Preliminary anatomical study indicates that members of this group have remained virtually unchanged for at least 50 million years (Ma). Anatomy of the crocodile lizard has been very poorly known because this endangered species is extremely rare in zoological and museum collections. Previous studies of the skeleton were fraught with errors because of the poor quality of available specimens. This, coupled with the complete absence of fossils younger than the Cretaceous (65 Ma), has made it very difficult to place this group on the family tree of lizards. Fortunately, 15 complete specimens from the University of Florida and the Field Museum of Natural History (FMNH) in Chicago, Illinois will make the skeletal anatomy of this strange creature accessible to science. The current project will describe skeletal anatomy and anatomical changes between hatchling and adults and correct current misconceptions regarding the anatomy of crocodile lizards. Changes in anatomybetween newborn and adults also will be described in related lizards. Additionally, FMNH recently acquired a fossil from Wyoming representing the first known fossil crocodile lizard younger than the Cretaceous. Preliminary work indicates that the new fossil is all but identical to the living form. This is significant because of the age of the fossil (about 50 Ma) and the distance separating the two species (living crocodile lizards come only from East Asia, whereas the fossil is from the western United States). This project will describe and name the new fossil form and develop a new systematic analysis to place it on the family tree of lizards. These data will then be used to address the great anatomical similarity between the fossil and the living form, which is properly regarded as a "living fossil." Understanding the placement of any animal group on the tree of life is central to studying evolutionary processes (such as long-term persistence of anatomical forms, as evidenced by crocodile lizards) and to developing hypotheses about the origin and history of biological diversity. Additionally, the new family tree will be used to compare the occurrences of crocodile lizards to other groups with similar distributions. For example, several groups of fossil and living fishes exhibit remarkably similar distributions, which means that the study of crocodile lizards may become broadly significant to interpreting the history of the western North American and Asian landmasses. Broader impacts of this study include: 1) training of a doctoral student in vertebrate anatomy and systematics; 2) the first detailed anatomical study of the crocodile lizard, a globally endangered species that has been very poorly studied up to now and that has excellent potential to attract broad public interest in science and global change because of its rarity and interesting fossil record; 3) description and naming of a remarkable new and important fossil species; 4) dissemination of research findings via scientific publications, lectures and websites; 5) inclusion of 3-dimensional images of crocodile lizards on the Digital Morphology Website at the University of Texas (www.digimorph.org/index.phtml; note that this site attracts a great deal of interest from non-scientists because of its arresting 3-D images of animal skeletons based on cat-scanning technology); 6) training of inner-city high school students in Chicago through BioOutreach and Project Exploration, two programs designed to excite student interest in science and augment their regular classroom experiences.
