Roberta Millstein Portrait

Position Title
Professor Emerit



  • Ph.D., Philosophy with minor in History of Science and Technology, University of Minnesota, 1997
  • M.A., Philosophy, University of Minnesota, 1993
  • A.B., Computer Science and Philosophy (double major), Dartmouth College, 1988


Roberta L. Millstein is an Emerit Professor in the Department of Philosophy at UC Davis, retired from teaching but still researching.  She is a AAAS Fellow (elected 2022). She is affiliated with the Science and Technology Studies (STS) Program and she co-runs UCD's PhilBio Lab with Jim Griesemer.

She is a Co-Editor of the peer-reviewed open-access online journal Philosophy, Theory, and Practice in Biology. She is also a Co-Chair of the History and Philosophy of Science section and a member of Council for the American Association for the Advancement of Science, Pacific Division (AAAS-PD). She is on the editorial boards for the Stanford Encyclopedia of Philosophy and the journal Philosophy of Science.

Her past service for the profession includes the following roles: Senior Co-Chair of the PSA Women's Caucus; member of the Governing Board and the Program Committee for the PSA; Secretary, member of Council, and Program Co-chair for the International Society for the History, Philosophy, and Social Studies of Biology (ISHPSSB), and an Elected Member-at-Large for the Section on History and Philosophy of Science of the AAAS.

Research Focus

Professor Emerit Millstein's research is in the philosophy of science, the history & philosophy of biology, and environmental ethics. She is particularly interested in evolutionary biology, ecology, and environmental issues, and the intersections between them.

With respect to evolutionary biology, she has particularly focused on central processes in evolution such as natural selection, random drift, sexual selection, and social selection, as well as central concepts in evolution such as fitness, population, metapopulation, race, and environment. This has included analysis of the general philosophy of science concepts of chance, probability, causation, causal processes, and determinism/indeterminism, and the ways in which they manifest (or fail to manifest) within evolutionary processes. Her conceptual work has been informed by her historical work, which includes analysis of some central 20th century debates in evolutionary biology, such as the neutral and “nearly neutral” theories of evolution and the empirical study of the land snail Cepaea nemoralis in the wild.

With respect to ecology, she has examined the historical and contemporary connections between ecology and population genetics. As part of a more extensive research project, she has re-interpreted and defended the work of 20th century ecologist (forester, wildlife manager, conservationist) Aldo Leopold, analyzing land communities (roughly similar to biotic communities/ecosystems), interdependence, functions/functioning, and predator/prey dynamics. Inasmuch as these ideas arise in the context of Leopold's land ethic, this project is also a project in environmental ethics. She is currently working on a book length analysis and defense of the land ethic, tentatively titled The Land Is Our Community: A Land Ethic for the New Millennium. Other work in environmental ethics examines the implications of the environmental impacts of GMOs and argues for how we ought to think of the field of environmental ethics.


  • Millstein, Roberta L. (2020), “Functions and Functioning in Aldo Leopold’s Land Ethic and in Ecology,” Philosophy of Science 87: 1107-1118.
  • Millstein, Roberta L. (2018), “Understanding Leopold's Concept of 'Interdependence' for Environmental Ethics and Conservation Biology,” Philosophy of Science 85: 1127-1139.
  • Millstein, Roberta L. (2016), “Genetic Drift” in Edward N. Zalta (ed.), The Stanford Encyclopedia of Philosophy.
  • Millstein, Roberta L. (2016), “Probability in Biology: The Case of Fitness” in A. Hájek and C. R. Hitchcock (eds.), The Oxford Handbook of Probability and Philosophy, Oxford: Oxford University Press, 601-622.
  • Millstein, R. L. (2015) Re-examining the Darwinian basis for Aldo Leopold’s Land Ethic, Ethics, Policy & Environment 18: 301-317.
  • Millstein, R. L. (2015) Thinking about populations and races in time, In Studies in History and Philosophy of Biological and Biomedical Sciences 52: 5-11. Special issue on Genomics and Philosophy of Race, R. G. Winther, R. L. Millstein, and R. Nielsen (Eds.)
  • Millstein, R. L. (2014) How the concept of population resolves concepts of environment, Philosophy of Science 81: 741-755.
  • Millstein, R. L. (2013) Natural selection and causal productivity: A reply to Glennan, In H. Chao, S. Chen, and R. L. Millstein (Eds.), Mechanism and Causality in Biology and Economics, Springer, 147-163.
  • Millstein, R. L. (2012) Darwin's explanation of races by means of sexual selection, In Studies in History and Philosophy of Biological and Biomedical Sciences 43: 627-633.
  • Millstein, R. L. (2010) The concepts of population and metapopulation in evolutionary biology and ecology, In M. A. Bell, D. J. Futuyma, W. F. Eanes, and J. S. Levinton (Eds.), Evolution Since Darwin: The First 150 Years, Sunderland, MA: Sinauer, 61-86.