YIBS 1998-1999 Annual Report
IV. RESEARCH CENTERS
Elisabeth Vrba, Director
A highlight in Elisabeth Vrba's ECOSAVE program was the completion of the volume Deer, Antelopes, Giraffes, and Relatives: Past, Present and Future (eds Vrba, E.S. and Schaller, G.B.) with chapters from 22 international contributors. This volume was sponsored by YIBS and the Wildlife Conservation Society, New York, to which Elisabeth was recently elected as a Fellow. The volume will appear on the spring 2000 booklist of Yale University Press. The following topics on deer, antelopes and relatives were discussed: their fossil record, origins, evolution, diversification, systematics; palaeobiogeography, including major migrations; past tectonic and palaeoclimatic changes associated with ruminant evolution; causes of major speciation and extinction episodes; ecology and behaviour in the past; systematics of living species based on gene sequences, hard and soft anatomy and behaviour; ecology, behaviour and evolution; present biogeography; what the past and present information indicates for conservation : population conservation genetics; which taxonomic level and which taxa and ecosystems merit conservation priority; implications of greenhouse warming; management and role of zoos, national parks, etc.; 'sustainable use' on game ranches and by local peoples; reintroductions.
New systematic analyses of living and extinct antelopes (Bovidae) culminated in the monographic publication 1 (see Vrba publications 1 7 below) and in the first cladistic analysis of bovids that combines behavior and ecology with soft and hard anatomy (publ. 6). Collaboration with other members of the Middle Awash Research Program on new fossil finds from Late Neogene Ethiopian fossil strata resulted in the recent publication 3 in Science on the environment and behavior of the new hominid species Australopithecus garhi. A comprehensive new analysis of the all-African fossil record of larger mammals over the past 22 million years was completed and used to test hypotheses of macroevolution (publication 7). A long-standing interest in the relationships between climate, evolution, and organismal growth is represented by an analysis with a new statistical growth model of brain growth data in chimpanzees and humans (publication 2).
Papers (appeared or in press) by Elisabeth Vrba during 1998-1999:
1. Vrba, E.S. 1998. (Monograph.) New fossils of Alcelaphini and Caprinae (Bovidae, Mammalia) from Awash, Ethiopia, and phylogenetic analysis of Alcelaphini. Palaeontologia africana 34: 127- 198.
2. Vrba, E.S. 1998. Multiphasic growth models and the evolution of prolonged growth exemplified by human brain evolution. Journal of Theoretical Biology 190: 227-239.
3. de Heinzelin, J., Clark, J.D., White, T., Hart, W., Renne, P., WoldeGabriel, G., Beyene, Y. and Vrba, E.S. 1999. Environment and behavior of 2.5-million-year-old Bouri hominids. Science 284: 625-629.
4. Vrba, E.S. and Schaller, G.B. (eds. of book) In press. Deer, Antelopes, Giraffes, and Relatives: Past, Present and Future. Yale University Press, New Haven, Connecticut.
5. Vrba, E.S. and Schaller, G. B. In press. Introduction. In Vrba, E.S. and Schaller, G.B. (eds.) Deer, Antelopes, Giraffes, and Relatives: Past, Present and Future. Yale University Press, New Haven, Connecticut.
6. Vrba, E.S. and Schaller, G. B. In press. Phylogeny of Bovidae (Mammalia) based on behavior, glands and skull morphology. In Vrba, E.S. and Schaller, G.B. (eds.) Deer, Antelopes, Giraffes, and Relatives: Past, Present and Future. Yale University Press, New Haven, Connecticut.
7. Vrba, E.S. In press. Major features of Neogene Mammalian Evolution in Africa. In T.C. Partridge and R. Maud (eds.), Cenozoic Geology of Southern Africa. Oxford University Press, Oxford, United Kingdom.
8. Vrba, E.S. In press. Habitat theory in relation to the evolution in African Neogene biota and hominids. In T.G. Bromage and F. Schrenk (eds.), African Biogeography, Climate Change, and Early Hominid Evolution. Part of New Series on Human Evolution (Series Eds Wood, B. and Ciochon, R.). Oxford University Press, Oxford, United Kingdom.
The Center for the Study of the Ecology and Systematics of Animals on the Verge of Extinction (ECOSAVE) focuses on understanding the biodiversity crisis on two time-scales. A long-term view is provided by analyses of evidence for ecosystem changes in the fossil record and the reconstruction of phylogenetic relationship of extinct and extant taxa. A more contemporary view is provided by genetic analyses of extant species. Understanding the historical and contemporary patterns of biodiversity provides the scientific basis for developing effective strategies for maximizing biodiversity. One major initiative this past year was the establishment of the Molecular Systematics and Conservation Genetics Laboratory directed by Gisella Caccone. This facility has both a research and training mission.
Two research projects have focused on tortoises. One study was on endemic Madagascar tortoises, two of which are considered rare and endangered. The results showed that contrary to accepted classifications, Madagascar tortoises form a monophyletic clade consistent with a single founding of tortoises on Madagascar. This work is "in press" and was done in collaboration with workers from the Wildlife Conservation Society and a Yale undergraduate. The second tortoise project concerns the conservation genetics and phylogenetics of giant Galápagos tortoises. To date over 2,000 blood samples have been collected from several subspecies of these tortoises. These samples will be analyized using modern DNA technology. This past year the phylogenetic relationships of the subspecies were determined as well as identifying the likely closest living relative of the Galápagos tortoises (manuscript submitted); surprisingly, this was the smallest mainland South American tortoise, the Chaco tortoise. Also, from these results we are confident that we will be able to determine the island origin of Galápagos tortoises based on DNA data. This will be useful in determining the origin of captive animals of unknown origin that then might be placed back into the wild if the subspecies is threatened.
Another project, with graduate student Kristin Saltonstall, concerns an invasive plant, Phragmites, that has recently undergone a large range expansion in both freshwater and brackish wetlands. It is threatening native biodiversity. Why this species is suddenly spreading is not clear; one hypothesis is that a new genotype has colonized the United States. Genetic studies of modern populations compared to herbarium specimens and old core samples will determine if there has been a genetic shift. The data that is being collected is a combination of DNA sequences, microsatellites, and karyotypes.
In collaboration with Dr. Caccone, Geology and Geophysics Professor Jacques Gauthier, has been studying zantusiid lizards native to the Southwest United States. Based on mitochondrial DNA sequences, it appears that a new species has been identified, Xantusia arizonae. Like all other xantusiids, it is essentially a troglodyte living its entire life in a confined space from which it seldom emerges. All aspects of its biology, its low metabolism, slow growth and reproductive rates, dark-adapted eyes, suit it to the challenges of its preferred microhabitat. The newly recognized Xantusia arizonae represents the earliest and least modified derivative of the rock-morph line. Recognition of a new rock-morph species will have important implications for conservation efforts in Arizona. Xantusia vigilis - the Yucca dweller to which Xantusia arizonae is currently allied as a subspecies - is widespread, locally abundant and lives in a readily renewable habitat, so it enjoys no special protection in Arizona. That poses a potential problem for the Xantusia arizonae rock-morph, however, as it lives primarily beneath exfoliating granite, a habitat that replaces only very slowly. Habitat modification has always been a prime factor in extinction. To ensure robust local populations of Xantusia arizonae, the state of Arizona should consider modifying current practices, for example, by outlawing crowbar use and other destructive collecting practices in rocky habitats.
Teaching and training:
Part of the mission of the Molecular Systematics and Conservation Genetics Laboratory is teaching and training both graduate and undergraduate students. This past year, Dr. Caccone offered one formal course: Molecular Approaches to Systematics, Conservation Genetics and Behavioral Ecology. A new course has been planned for the fall: Laboratory in Molecular Systematics. In addition, four graduate students and two undergraduates received training directly in the laboratory. Six more students received training on use of our computer facilities for analysis of molecular data.
Major accomplishments in Jacques Gauthier's laboratory included reorganization of the Divisions of Vertebrate Zoology and Vertebrate Paleontology in the Peabody Museum to better meet research and teaching needs of the Departments of Ecology and Evolutionary Biology, Geology and Geophysics, and Anthropology, as well as the Environmental Sciences Facility, Yale Institute for Biospherics and the Yale School of Forestry and Environmental Studies. Jacques organized the Ostrom Symposium: New Perspectives on the Origin and Early Evolution of Birds. A group of 24 scientists from around the world came to New Haven over the weekend of February 13 -14 to address an audience of 500 honoring Yale Emeritus Professor John Ostrom's contributions to dinosaur paleontology and evolution. Jacques is currently editing the 35 invited papers submitted to the Ostrom Symposium Volume, which should appear in 2000. He also produced, directed and wrote an exhibit entitled China's Feathered Dinosaurs' that opened on the weekend of the Ostrom Symposium and remained on display in the Yale Peabody Museum of Natural History for three months in the spring of 1999. A research highlight was the developmental and evolutionary analysis of the avian hand (publications 2 4 below) 1998-1999.
Papers (appeared or in press) by Jacques Gauthier during 1998-1999:
1. Britt, B., P. Makovicky, J. Gauthier. 1998. Postcranial pneumaticity in Archaeopteryx . Nature 395:374-376.
2. Gauthier, J. and G. Wagner. 1998. I,II,III or II,III,IV or both?: A solution to the problem or avian digit homology. Abstract In: Journal of Vertebrate Paleontology 18(3):45A-46A.
3. Wagner, G.P. and J.A. Gauthier. 1999. 1,2,3 = 2,3,4: A solution to the problem of the homology of the digits in the avian hand. Proceedings of the National Academy of Sciences 96:5111-5116.
4. Gauthier, J. and G. Wagner. 1999. 1-2-3 or 2-3-4 or both?: A solution to the problem of avian digit homology. Abstract In: American Society of Ichthyologists and Herpetologists (79th). Penn. State Univ., State College.
Karl K. Turekian, Director
The Center for the Study of Global Change accomplishes its goals through various ways: