Robert C. Lacy

Robert C. Lacy

Abstract

Stopping Evolution: Genetic Management of Captive Populations

Stopping evolution: Genetic management of captive populations. Captive populations can serve as sources for reintroduction of extirpated wild populations, sources for reinforcing genetically or demographically fragile populations, appropriate models for research, and foci of conservation education programs. Yet all these values depend on a captive population maintaining a genetic composition comparable to the wild population it represents. This requires breeding programs that minimize damage from inbreeding, slow random genetic drift, and minimize adaptation to captive conditions (domestication). Thus, we wish to stop evolution of the captive population into an organism quite different from the wild progenitors. Genetic management strategies for captive populations have evolved rapidly over the last 20 years from simply avoiding inbreeding, to equalizing family sizes, to equalizing founder contributions, to minimizing mean kinship. Through computer simulations, the effectiveness of strategies for preventing evolutionary change in captive breeding programs was evaluated. Pedigree management techniques are identified that minimize the random genetic change, reduce the rate of domestication, and are robust to small numbers of errors in our knowledge of the pedigree structure. Still, rates of genetic change in captive populations of the size often maintained in zoos may be too high to provide assurance that long-term captive populations will retain their genetic diversity and integrity.

Biography

Robert Lacy has been the Population Geneticist for the Department of Conservation Biology at Brookfield Zoo since 1985. He was trained in quantitative genetics (B.A., M.A., Wesleyan University), evolutionary biology, ecology, and population genetics (Ph.D., Cornell University). He has published papers in evolutionary theory, genetics, population ecology, taxonomy, behavior, conservation, and wildlife management. He has developed techniques for pedigree analysis, and his computer software is used by zoos throughout the world for managing breeding programs. Software he developed for modeling population dynamics is used by conservationists, wildlife managers, researchers, and students in governmental agencies, NGOs, and universities throughout the world.

Relevant Publications

Lacy, R.C. 1994. Managing genetic diversity in captive populations of animals. Pages 63-89 in M.L. Bowles and C.J. Whelan (eds.), Restoration and Recovery of Endangered Plants and Animals. Cambridge University Press, Cambridge.

Ballou, J.D. and R.C. Lacy. 1995. Identifying genetically important individuals for management of genetic diversity in pedigreed populations. Pages 76-111 in J.D. Ballou, M. Gilpin, and T.J. Foose (eds.), Population Management for Survival & Recovery. Analytical Methods and Strategies in Small Population Conservation. Columbia University Press, New York.

Lacy, R.C. 1997. Importance of genetic variation to the viability of mammalian populations. Journal of Mammalogy 78:320--335.

Lacy, R.C. and J.D. Ballou. 1998. Effectiveness of selection in reducing the genetic load in populations of Peromyscus polionotus during generations of inbreeding. Evolution 52:900--909.

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