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James L. Hamrick

Plant Sciences, Rm 2203
Lab Phone:
Plant Sciences, Rm 2512
Office Phone:
Research Interests:

My laboratory studies the genetics and evolution of natural plant populations. We are particularly interested in the genetic structure of plant populations and in those factors that influence the development of genetic structure; natural selection, the mating system, pollen movement and seed dispersal.

  • National Science Foundation. Interactive roles of Predation and Hybridization on Populations Dynamics of an Endangered Lupinus Species. 2008-2011.
  • National Science Foundation. Dissertation Research: Comparative phylogeography of neotropical trees. 2008-2009.
  • National Science Foundation. PIRE: Genetics of Invasive Species Exchanged Between the Southeastern U.S. and China, Taiwan and Hong Kong. 2007-2012.
  • US Department of Agriculture. Long term conservation of Crategus X sinica, a Valuable Medicinal Plant of the South Sinai Mountains. 2007-2009.
Selected Publications:
  • Parker, K. C., D. W. Trapnell, J. L. Hamrick and W. C. Hodgson. 2014. Genetic and morphological contrasts between wild and anthropogenic Agave parryi var. hauachucensis  populations in south-eastern Arizona. Annals of Botany, in press.
  • Shirk, R. Y., J. L. Hamrick, C. Zhang and S. Qiang. 2014. Patterns of genetic diversity reveal multiple introductions and subsequent range expansion in invasive populations of Geranium carolinianum L. (Geraniaceae). Heredity, in press.
  • Shirk, R. Y., T. C. Glenn, S-M Chang and J. L. Hamrick. 2013. Development and characterization of microsatellite primers in Geranium carolinianum (Geraniaceae) with 454 sequencing. Applications in Plant Sciences, 1:130006.
  • Trapnell, D. W., J. L. Hamrick, C. D. Ishibashi and T. R. Kartzinel. 2013. Genetic inference of epiphytic orchid colonization; it may only take one. Molecular Ecology, 22:3680-3692.
  • Gormally, C. L., J. L. Hamrick, and L. A. Donovan. 2013. Comparison of quantitative trait variation and allozyme diversity within and among populations of sea oats, Uniola paniculata, across an environmental gradient. Conservation Genetics, 14:185-193.
  • Poelchau, M. F. and J. L. Hamrick. 2013b. Paleodistribution modeling does not support disjunct Pleistocene refugia in Central American plant taxa. Journal of Biogeography, 40:662-675.
  • Poelchau, M. F. and J. L. Hamrick. 2013a. Comparative phylogeography of three Central American tree species. Journal of Biogeography, 40:618-631.
  • Fuchs, E. J. and J. L. Hamrick. 2013. Spatial distribution of Guaiacum sanctum
  • (Zygophyllaceae) seedlings and samplings relative to canopy cover. Int. J. Trop. Biol. 61:1521-1533.
  • Poelchau, M. F. and J. L. Hamrick. 2012. Differential effects of landscape level environmental features on genetic structure in three codistributed tree species in Central America. Molecular Ecology 21:4970-4982.
  • Trapnell, D. W., J. L. Hamrick, and V. Negron-Ortiz. 2012. Genetic diversity within a threatened, endemic southeastern North American species, Euphorbia telephioides (Euphorbiaceae). Conservation Genetics 13:743-751.
  • Hamrick, J. L. 2012. Tropical breeding systems: one and done? Heredity 109:330-331.
  • Tompkins, R. D., D. W. Trapnell, J. L. Hamrick and W. C. Stringer. 2012. Genetic variation within and among remnant big bluestem (Andropogon gerardii, Poaceae) populations in the Carolinas. Southeastern Naturalist 11:455-468.
  • Zaghloul, M. S., J. L. Hamrick, and A. A. Moustafa. 2012. Conservation genetics of Sinai’s remnant populations of Moringa peregrina, an economically valuable medicinal plant. Conservation Genetics 13:9-19.
  • Hamrick, J. L. and D. W. Trapnell. 2011. Using population genetic analyses to understand seed dispersal patterns. Acta Oecologia 37:641-649.
  • Chang, S-M., E. Gonzales, E. Pardini, and J. L. Hamrick. 2011. Encounters of old foes on a new battle ground for an invasive tree, Albizia julibrissin Durazz (Fabaceae). Biol. Invasions 13:1043-1053.
  • Fuchs, E. J. and J. L. Hamrick. 2011. Mating system and pollen flow between remnant populations of the endangered tropical tree, Guaiacum sanctum (Zygophyllaceae). Conserv. Genet. 12:175-185.
  • Hamrick, J. L. 2010. Pollen and seed movement in disturbed tropical landscapes. pp. 190-211. In DeWoody, J. A., J. W., Bickham, C. H. Michler, K. M. Nichols, O. E. Rhodes, and K. E. Woeste (eds) Molecular Approaches in Natural Resource Conservation and Management. Cambridge Univ. Press, New York.
  • Parker, K. C., D. W. Trapnell, J. L. Hamrick, W. C. Hodgson, and A. J. Parker. 2010. Inferring ancient Agave cultivation practices from contemporary genetic patterns. Mol. Ecol. 19:1622-1637.
  • Gonzales, E., J. L. Hamrick, P. E. Smouse, D. W. Trapnell, and R. Peakall. 2010. The impact of landscape disturbance on spatial genetic structure in the Guanacaste tree,Enterolobium cyclocarpum (Fabaceae). J. Hered. 101:133-143.
  • Hufford, K. M., J. L. Hamrick, and S. L. Rathbun. 2009. Male reproductive success at three early life stages in the tropical tree, Platypodium elegans. Int. J. Plant Sci. 170:724-734.
  • Gonzales, E., J.L. Hamrick, and P.E. Smouse. 2008. Comparison of clonal diversity in mountain and piedmont populations of Trillium cuneatum (Melanthiaceae-Trilliaceae), a forest understory species. Am. J. Bot. 95:1254-1261.
  • Pardini, E.A., and J.L. Hamrick. 2008. Inferring recruitment history from spatial genetic structure within populations of the colonizing tree, Albizia julibrissin (Fabaceae). Mol. Ecol. 17:2865-2879.
  • Gonzales, E., J.L. Hamrick, and S-M. Chang. 2008. Identification of glacial refugia in southeastern North America by phytogeographical analyses of a forest understory plant, Trillium cuneatum. J. Biogeography 35:844-852.
  • Dunphy, B.K. and J.L. Hamrick. 2007. Estimation of gene flow into fragmented populations of Bursera simaruba (Burseraceae) in the dry-forest life zone of Puerto Rico. Am. J. Bot. 94:1786-1794.
  • Parker, K. C., D. W. Trapnell, J. L. Hamrick, W. C. Hodgson, and A. J. Parker. 2010. Inferring ancient Agave cultivation practices from contemporary genetic patterns. Mol. Ecol. 19:1622-1637.
  • Pardini, E. A. and J. L. Hamrick. 2007. Hierarchical patterns of paternity within crowns of Albizia julibrissin (Fabaceae). Am. J. Bot. 94:111-118.
  • Trapnell, D. W. and J. L. Hamrick. 2006. Floral display and mating patterns within populations of the neotropical epiphytic orchid, Laelia rubescens (Orchidaceae). Am. J. Bot. 93:1010-1018.

Ph.D Population Genetics, University of California - Berkeley 1970

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