Where life begins...

Dr. James Demastes

Dr. James Demastes
(319) 273-2022
McCollum Science Hall 70
  • Ph.D. 1996 Louisiana State University, Baton Rouge, LA., Department of Zoology and Physiology.
  • Dissertation: "Analysis of cospeciation: The effects of spatial and temporal scale."
  • M.S. 1990 Louisiana State University, Baton Rouge, LA., Department of Zoology and Physiology.
  • Thesis: "Host-parasite coevolutionary relationships in two assemblages of pocket gophers and chewing lice."
  • B.S. 1982 Secondary Science Education (biology major, chemistry minor), Auburn University, Auburn, AL.

Teaching Interests: 
Mammalogy and Field Zoology have been my main responsibilities but I am also very interested in any class dealing with evolution, the nature of science, and critical thinking (all of which I try to incorporate into any class). Thus, I enjoy teaching Organismal Diversity to our biology freshmen. As an evolutionary biologist, I am also enjoying the challenge of teaching the sophomore-level course, Ecological and Evolutionary Theory.

My research interests focus on host-parasite coevolution and zoogeography. My research in coevolution involves long-time collaborations with several researchers at other universities. We have been studying pocket gophers (Rodentia: Geomyidae) and their ectoparasitic chewing lice (Pthiraptera: Trichodectidae) for over 20 years. Our past, NSF-funded, work involved a gopher-louse assemblage distributed across much of Mexico (Spradling, et al., 2016). 

Dr. Theresa Spradling and I are currently working on a long-term study on the affects of range expansion on the population genetics of parasites along the Rio Grande. We have been studying this particular system since 1989 and are now applying modern techniques such as DNA fingerprinting to examine the genetic consequences of shifting species ranges.  This is an especially important question given the rapid environmental change (and subsequent range shifts) that are being observed today. This research has also been funded by NSF and has involved several UNI students. For more information, see our project web page:

Grant History

2014-Present Testing geographic range-expansion models: Parasite population genetics in a colonizing species. (with T. A. Spradling, UNI and J. E. Light, Texas A&M) National Science Foundation ($149,937)

2004-2008 Molecular Studies of Cospeciation Enhanced by Exhaustive Sampling and GIS Technology (with M.S. Hafner at Louisiana State University), National Science Foundation ($300,000)

1999-2000 Iowa Distributed Wind Generation Project (IDWGP), Avian Risk, Fatality and Disturbance at the IDWGP Wind Farm, Algona, IA ($24, 505).

1999 Iowa Department of Natural Resources contract for Inventory of the bats of White Pine Hollow State Preserve ($1587).

  • 2019 D. J. Hafner, M. S. Hafner, T. A. Spradling, J. E. Light, and J. W. Demastes. Temporal and spatial dynamics of competitive parapatry in chewing lice. Ecology and Evolution, 10.1002/ece3.5183.
  • 2019 Popinga, A.*, J. W. Demastes, T. A. Spradling, D. J. Hafner, and M. S. Hafner.  Host-parasite associations of the Cratogeomys fumosus species group and their chewing lice, Geomydoecus.  Therya, 10: 81-89 [*UNI undergraduate student).
  • 2019 Demastes, J. W., D. J. Hafner, M. S. Hafner, J. E. Light, and T. A. Spradling. Loss of genetic diversity, recovery, and allele surfing in a colonizing parasite, Geomydoecus aureiMolecular Ecology, 28:703-720.
  • 2018 Light, J. E., Harper, S., Johnson, K., Demastes, J., & Spradling, T.  Development and Characterization of 12 Novel Polymorphic Microsatellite Loci for the Mammal Chewing Louse Geomydoecus aurei (Insecta: Phthiraptera) and a Comparison of Next-Generation Sequencing Approaches for Use in Parasitology.  Journal of Parasitology,104:89-95.
  • 2016 Pietan, L. L.*, T. A. Spradling, and J. W. Demastes. The Mitochondrial Cytochrome Oxidase Subunit I Gene Occurs on a Minichromosome with Extensive Heteroplasmy in Two Species of Chewing Lice, Geomydoecus aurei and Thomomydoecus minor. PLOS ONE. (*UNI undergraduate student)
  • 2016 Spradling, T. A.,  J. W. Demastes, D.J. Hafner, P. L. Milbach*, F. A. Cervantes, and M. S. Hafner.  Systematic revision of the pocket gopher genus Orthogeomys.  Journal of Mammalogy.
    97:405-423. (*UNI undergraduate student)
  • 2015 Harper, S. E.**, T. A. Spradling, J. W. Demastes, and C. S. Calhoun*. Host behavior drives parasite genetics at multiple geographic scales: Population genetics of the chewing louse, Thomomydoecus minor.  Molecular Ecology. 24:4129-4144. (*UNI undergraduate student, ** UNI M.S. student)
  • 2014 Hafner, M. S., D. J. Hafner, E. E. Gonzales, J. W. Demastes, T. A. Spradling, and F. A. Cervantes. Rediscovery of the pocket gopher Orthogeomys lanius (Rodentia: Geomyidae) in Veracruz, Mexico. Journal of Mammalogy. 95:792-802.
  • 2013 Mathis, V. L., M. S. Hafner, M. S., D. J. Hafner, and J. W. Demastes. Thomomys nayarensis, a new species of pocket gopher from the Sierra del Nayar, Nayarit, Mexico. Journal of Mammalogy. 94: 983-994.
  • 2013 Mathis, V. L., M. S. Hafner, D. J. Hafner, and J. W. Demastes. Resurrection and Redescription of the pocket gopher Thomomys sheldoni from the Sierra Madre Occidental of Mexico. Journal of Mammalogy. 94: 544-560.
  • 2012 Demastes, J. W., T. A. Spradling, M. S. Hafner, D. J. Hafner, J. E. Light, G. R. Spies*. Cophylogeny on a fine scale: Geomydoecus chewing lice and their Pocket Gopher Hosts (Pappogeomys bulleri). Journal of Parasitology, 98:262-270. (*UNI undergraduate student)
  • 2011 Hafner, M.S., A. R. Gates, V.L. Mathis, J. W. Demastes and D. J. Hafner. Redescription of Thomomys atrovarius. Journal of Mammalogy. 92:1367-1382.
  • 2009 Hafner, M.S. , D.J. Hafner, J.W. Demastes, T. A. Spradling, G. L. Hasty, and J. E. Light. Evolutionary Relationships of pocket gophers of the Genus Pappogeomys (Rodentia: Geomyidae). Journal of Mammalogy, 90:47-56.
  • 2008 Richtsmeier, R.J.**, N.P. Bernstein, J.W. Demastes, and R. W. Black. Migration, gene flow, and genetic diversity within and among Iowa populations of ornate box turtles (Terrapene ornata ornata). Chelonian Conservation and Biology, 7:3-11. (**UNI M.S. student)
  • 2008 Hafner, D.J., M.S. Hafner, G.L. Hasty, T.A. Spradling, and J.W. Demastes. Evolutionary relationships of pocket gophers (Cratogeomys castanops species group) of the Mexican Altiplano. Journal of Mammalogy, 89:190-208.
  • 2007 Eastman, J.M.* *, T.A. Spradling, J.W. Demastes, and H. Hadow. Conservation genetic assessment of the blue-spotted salamander in Iowa. American Midland Naturalist, 158:233-239. (**UNI M.S. student)
  • 2007 Demastes, J. W., J. M. Eastman**, J. S. East**, and C. Spolsky. Phylogeography of the blue-spotted salamander, Ambystoma laterale (Caudata: Ambystomatidae). Am. Mid. Nat., 157:149-161. (**UNI M.S. student)
  • 2005 Hafner, M. S., J. E. Light, D. J. Hafner, S. V. Brant, T. A. Spradling, and J. W. Demastes. Cryptic species in the Mexican pocket gopher Cratogeomys merriami. Journal of Mammalogy, 86:1095-1108.
  • 2003 Demastes, J. W., A. L. Butt *, M. S. Hafner and J. L. Light. Systematics of a rare species of pocket gopher, Pappogeomys alcorni. Journal of Mammalogy, 84:753-761.  (*UNI undergraduate student)
  • 2003 Sinatra, Gale, Sherry S. Southerland, Frances McConaughy, and James W. Demastes. Intentions and beliefs in students' understanding and acceptance of biological evolution. Journal of Research in Science Teaching, 40:510-528.
  • 2003 Demastes, J. W., T. A. Spradling, and M. S. Hafner. Effects of spatial and temporal scale on cospeciation. Pp. 221-239 in "Tangled trees: Phylogeny, Cospeciation, and Coevolution". (R. D. M. Page, ed.). The University of Chicago Press, Chicago.
  • 2003 Hafner, M. S., J. W. Demastes, T. A. Spradling, and D. L. Reed. Cophylogeny in pocket gophers and chewing lice. Pp. 195-220 in "Tangled trees: Phylogeny, Cospeciation, and Coevolution". (R. D. M. Page, ed.). The University of Chicago Press, Chicago.
  • 2002 Demastes, J. W., T. A. Spradling, M. S. Hafner, D. J. Hafner, and D. L. Reed. Systematics and phylogeography of pocket gophers in the genera Cratogeomys and Pappogeomys. Molecular Phylogenetics and Evolution, 22:144-154.