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Paulette Bierzychudek

William Swindells, Sr. Professor of Natural Sciences

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    Gary Reiness

Biology-Psychology Hall

I’m a population biologist, and I work in the areas of ecology, evolution, and conservation biology. I teach and advise students in both Biology and Environmental Studies. I have undergraduate degrees in botany and in zoology from the University of Washington in Seattle, and a Ph.D. in ecology and evolutionary biology from Cornell University. I joined the faculty of Lewis & Clark College in 1995, after 15 years at Pomona College. For more information about my professional background, see my vita.

Nature is my inspiration, and I’m constantly asking “why” about the things that I see in the natural world. That’s why I became a population biologist who studies evolution, ecology, and conservation biology, particularly of terrestrial plants and insects. My research spans questions like how organismal traits evolve, what factors make populations change in size, and how humans can successfully coexist with wild species. I’ve worked in eastern U.S. deciduous forests, the alpine meadows of Colorado, tropical habitats in Costa Rica, and here in the Pacific Northwest.
My courses reflect these interests. My goal as a teacher is to foster my own students’ biological interests, their skills in scientific and quantitative reasoning and effective oral and written communication, and their confidence. In addition to being a member of
the Biology Department, I also serve as a faculty member in the Environmental Studies



Biology 141
Biology 335
Biology 390


Publications (* indicates student co-author):

  • Clements, H.* and P. Bierzychudek. 2017. Can the persistent seed bank contribute to the passive restoration of urban forest fragments after invasive species removal? Ecological Restoration 35(2): 156-166.
  • Bierzychudek, P. and K.  Warner. 2015. Modeling caterpillar movement to guide habitat enhancement for Speyeria zerene hippolyta, the Oregon silverspot butterfly. Journal of Insect Conservation 19(1): 45-54. 
  • Bierzychudek, P. 2014. Plant biodiversity and population dynamics. pp. 29-65 In: R. K. Monson (ed.) The Plant Sciences, vol. 8: Ecology and the Environment. Springer Science+Business Media New York. 
  • McHugh, A.*, P. Bierzychudek, C. Greever*, T. Marzulla*, R. VanBuskirk and G. Binford. 2013. A molecular phylogenetic analysis of Speyeria and its implications for the management of the threatened Speyeria zerene hippolyta. Journal of Insect Conservation 17(6): 1237-1253. 
  • Crone, E.E., M.M. Ellis, W. F. Morris, A. Stanley, T. Bell, P. Bierzychudek, J. Ehrlen, T. N. Kaye, T. M. Knight, P. Lesica, G. Oostermeijer, P. F. Quintana-Ascencio, T. Ticktin, T. Valverde, J. L. Williams, D. F. Doak, R. Ganesan, K. McEachern, A. S. Thorpe, and E. S. Menges. 2013. Ability of matrix models to explain the past and predict the future of plant populations. Conservation Biology 27(5): 968-978. 
  • Ellis, M.M., Williams, J.L., Lesica, P., Bell, T.J., Bierzychudek, P., Bowles, M., Crone, E.E., Doak, D.F., Ehrlen, J., Ellis-Adam, A., McEachern, K., Ganesan, R., Latham, P., Luitjen, S., Kaye, T.N., Knight, T.M., Menges, E.S., Morris, W.F., den Nijs, H., Oostermeijer, G., Quintana-Ascencio, P.F., Shelly, J.S., Stanley, A., Thorpe, A., Ticktin, T., Valverde, T., Weekley, C. 2012. Matrix population models from 20 studies of perennial plant populations. Ecology 93(4): 951-951 
  • Crone, E., Menges, E., Ellis, M., Bell, T., Bierzychudek, P., Ehrlen, J., Kaye, T., Knight, T., Lesica, P., Morris, W., Oostermeijer, G., Quintana-Ascensio, P., Stanley, A., Valverde, T., Ticktin, T., and Williams, J. 2011. How do plant ecologists use matrix models? Ecology Letters 14:1-8. 
  • Bierzychudek, P., Warner, K.A., McHugh, A.* and L. Thomas*. 2009. Testing the host-finding ability of a monophagous caterpillar in the field. Ecological Entomology 34(5): 632-637.
  • Warner, K. A. and P. Bierzychudek. 2009. Does marking with fluorescent powders affect the survival or development of larval Vanessa cardui? Entomologia Experimentalis et Applicata. 131(3): 320-324. 
  • Schemske, D. W. and P. Bierzychudek. 2007. Spatial differentiation for flower color in the desert annual Linanthus parryae: was Wright right? Evolution 61(11):2528-2543. (this paper was the focus of a “News of the Week” piece in Science on October 19, 2007: Pennisi, E. 2007. Natural selection, not chance, paints the desert landscape. Science 318:376)
  • Kruse, R.*, Bend, E.*, and P. Bierzychudek. 2004. Native plant regeneration and introduction of non-natives following post-fire rehabilitation with straw mulch and barley seeding. Forest Ecology and Management 196(2-3):299-310.
  • Johnson, E.B*, P. Bierzychudek, and H.H. Whiteman. 2003. Potential of prey size and type to affect foraging asymmetries in tiger salamander larvae (Ambystoma tigrinum nebulosum). Canadian Journal of Zoology 81:1726-1735.
  • Schemske, D. W. and P. Bierzychudek. 2001. Evolution of flower color in the desert annual Linanthus parryae: Wright revisited. Evolution 55(7): 1269-1282.
  • Turelli, M., D. W. Schemske, and P. Bierzychudek. 2001. Stable two-allele polymorphisms maintained by fluctuating fitnesses and seed banks: protecting the blues in Linanthus parryae. Evolution 55(7): 1283-1298.
  • Bierzychudek, P. 1999. Looking backwards: assessing the projections of a transition matrix model. Ecological Applications 9(4):1278-1287.
  • Roy, B.A. and P. Bierzychudek. 1993. The potential for rust infection to cause natural selection in apomictic Arabis holboelli (Brassicaceae). Oecologia 95:533-541.
  • Bierzychudek, P. 1990. Demographic consequences of sexuality and apomixis in Antennaria. pp. 293- 307 In: Kawano, S. (ed.) Biological Approaches and Evolutionary Trends in Plants, Academic Press, London.
  • Bierzychudek, P. 1990. The adaptive significance of sexual reproduction in plants. pp. 51-91 In: Mangel, M. (ed.) Some mathematical questions in biology – sex allocation and sex change: experiments and models. American Mathematical Society, Providence, R. I.
  • Bierzychudek P. 1989. Environmental sensitivity of sexual and apomictic Antennaria: do apomicts have general-purpose genotypes? Evolution 43(7): 1456-1466.
  • Bierzychudek P. and V. Eckhart*. 1988. Spatial segregation of the sexes of dioecious plants. American Naturalist 132:34-43.
  • Bierzychudek, P. 1987. Resolving the paradox of sexual reproduction: a review of experimental tests. pp. 163-174 in: Stearns, S. (ed.) The Evolution of Sex and Its Consequences. Birkhauser-Verlag, Basel.
  • Bierzychudek, P. 1987. Patterns in plant parthenogenesis. pp. 197-217 in: Stearns, S. (ed.) The Evolution of Sex and Its Consequences. Birkhauser-Verlag, Basel.
  • Bierzychudek, P. 1987. Pollinators increase the cost of sex by avoiding female flowers. Ecology 68(2):444-447.
  • Bierzychudek, P. 1985. Patterns in plant parthenogenesis. Experientia 41:1255-1264.
  • Bierzychudek, P. 1984. Determinants of gender in jack-in-the-pulpit: the influence of plant size and reproductive history. Oecologia 65(1): 14-18.
  • Bierzychudek, P. 1984. Assessing “optimal” life histories in a fluctuating environment: the evolution of sex-changing by jack-in-the-pulpit. American Naturalist 123:829-840.
  • Bierzychudek, P. 1982. The demography of jack-in-the-pulpit, a forest perennial that changes sex. Ecological Monographs 52-335-351. (later excerpted in BioScience 33:196-197).
  • Bierzychudek, P. 1982. Life histories and demography of temperate forest herbs: a review. New Phytologist 90:757-776.
  • Best, L. and P. Bierzychudek. 1982. Pollinator foraging on foxglove (Digitalis purpurea): a test of a new model. Evolution 36(1): 70-79.
  • Bierzychudek, P. 1981. Asclepias, Lantana, and Epidendrum: a floral mimicry complex? Reproductive Botany, supplement to Biotropica: 54-58.
  • Bierzychudek, P. 1981. Pollinator limitation of plant reproductive effort. American Naturalist 117: 838- 840.

Academic Credentials

B.S. in Botany, 1974, U. of Washington
B. A. in Zoology, 1974, U. of Washington
Ph.D. in Ecology and Evolutionary Biology, 1981, Cornell University

Investigations in Ecology and Environmental Science (Bio 141)
Ecology (Bio 335)
Evolution (Bio 390)
Calculus and Statistics for Modeling the Life Sciences (Math 123)
Dangerous Scientific Ideas (E&D)

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