white mtn  
Associate Professor of Biology
Department of Biological Sciences
921 S. 8th Avenue, Stop 8007
Idaho State University
Pocatello, ID  83209-8007 USA
email: willcha2@isu.edu

Curator of Botany
Ray J. Davis Herbarium
Idaho Museum of Natural History
921 S. 8th Avenue, Stop 8096
Idaho State University
Pocatello, ID  83209-8096 USA
208-282-3168/FAX 282-5893

Ecology and Evolutionary Genetics of Plant Reproduction and Dispersal,

Pollination and Seed Dispersal Biology, Mating System Evolution, Gynodioecy
Molecular Ecology, Population and Quantitative Genetics, Behavior

Research    Teaching       Students     Publications     CV     Etc.


My research examines the interelationships between plant ecology and population genetics, and how these in turn influence the evolution of plant reproduction.  In this regard I study things like how differences in fruit and seed morphology affect dispersal and gene flow, how pollinator behaviors differ in relation to flower and inflorescence size or density, and how this in turn affects plant outcrossing rates, etc.  Most projects involve both a field and laboratory component.  Much of the field work currently takes place at The Rocky Mountain Biological Laboratory, near Crested Butte, Colorado.  In the lab I use a number of genetic markers (allozymes, nuclear microsatellites, AFLPs, and chloroplast DNA RFLPs and sequences) to examine the genetic consequences of variation in reproductive ecology and infer the ecological and evolutionary history of different plant populations and species.  I also collaborate with other researchers and students to apply molecular genetic techniques to answer ecological and evolutionary questions about a variety of other organisms, both plants and animals.  Several of my main projects are outlined below:

Hermaphrodite Flower Female Flower

1.  Evolution of Gynodioecy in Geranium richardsonii.  Gynodioecy is the production of separate hermaphroditic and female individuals in a population.  Femaleness, or loss of male reproductive function, is caused by one or more male-sterility genes typically located in the mitochondrial genome.  Male sterility should be at a fitness disadvantage unless it is compensated for by increased female reproductive success relative to hermaphrodites.  My research with Geranium richardsonii examines several hypotheses for the selective maintenance of male sterility including resource allocation to flowers and seeds (female flowers are smaller, but produce more seeds than hermaphrodites), and self-fertilization and inbreeding depression (females cannot self, while hermaphrodites do so at rates > 50% and appear to suffer substantial inbreeding depression at different stages of the life cycle).  Additionally, relative fitness of the genders is density- and frequency-dependent, with females suffering pollen limitation when at high frequency.  I am investigating this phenomenon of density- and frequency-dependent fitness at a number of different spatial scales (local neighborhood, population, metapopulation).  I am also investigating the mode of inheritance of male-sterility through a multi-generation crossing experiment.  Finally, I am developing chloroplast DNA markers to investigate gene flow through seeds, and its relation to dispersal of male-sterility genes.

2.  Reproductive Ecology and Genetics of Delphinium species.  The genus Delphinium (Ranunculaceae), or Larkspurs is globally distributed and over 60 species occur in North America.  Larkspurs are pollinated predominantly by bumblebees and hummingbirds.  I have been investigating the reproductive biology, population genetics, and mating systems of two common species of the Western US, Delphinium nuttallianum, and D. barbeyi. Delphinium nuttallianum blooms shortly after snowmelt and has only 5-10 flowers on a single stalk.  This species is highly outcrossed and hence shows little spatial genetic structure.  Delphinium barbeyi blooms later, and has hundreds of flowers on multiple stalks.  Self pollination by geitonogamy (between flowers on the same plant) reduces outcrossing to about 50%, and populations are highly structured in space at a number of scales.  With students and collaborators I am currently investigating the effect of variation in  inflorescence size and plant density on the mating systems of these and other Delphinium species.


3.  Alternative Male Mating Strategies and Multiple Paternity in Burying Beetles. In collaboration with
Dr. Rosemary Smith (ISU), I have been investigating the paternity of burying beetle (Nicrophorus sp.) broods using microsatellite markers.  Burying beetles have biparental care of their brood, which is raised on a buried small mammal carcass as a resource.  Larger males are at a reproductive advantage in securing a carcass and defending it against intruding males.  Smaller males may adopt a "female mimic" strategy in which they are able to sneak copulations and thus gain at least partial paternity of broods they do not help to raise.  Additionally, females may be able to store sperm and thus not all offspring within the brood may by the progeny of the resident male.  Using highly variable microsatellite DNA markers we are assessing the prevalence of multiple paternity in the field and the success of alternative male strategies in laboratory-raised broods.

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I've taught several courses since coming to ISU.  There are links to each course web site for those I am currently teaching.  I am also involved in teaching and mentoring research students at The Rocky Mountain Biological Laboratory each summer.

General Ecology - BIOL 209.  4 credits; (Fall 2000)

Fall Flora - BIOL 2213. 2 credits. Identification and natural history of regional fall flora. Field trips, collections, laboratory examination of plant material.  Every Fall (Fall 2011)

Spring Flora - BIOL 2214. 2 credits. Identification and natural history of regional spring flora. Field trips, collections, laboratory examination of plant material.  Every Spring (Spring 2010)

Ecological Topics - BIOL 318/518.  2 credits.  Molecular Techniques in Ecology.  PREREQ. BIOL 209 (Fall 1999).

General Genetics - BIOL 358.  3 credits.  Basic principles of heredity and variation including transmission (Mendelian), molecular, and population genetics.  PREREQ:  BIOL 101 AND 102, AND BIOL 206.  Every semester (Fall 2001, Spring 2006)

Systematic Botany - BIOL 412/512.  4 credits.  Study of the classification and evolution of flowering plants, and techniques of phylogeny reconstruction based on molecular and morphological characters.  Collection and identification of local flora.  Field trips.  PREREQ: BIOL 101 AND 102, BIOL 358 and 417 recommended.  Every Spring semester (Fall 2001, Spring 2003, 2004, 2008).

Plant-Animal Interactions - BIOL 442/542.  3 credits.  Coevolutionary relationships of plants and animals emphasizing pollination, herbivory, parasitism, frugivory/seed dispersal and evolution of plant/animal form and function.  PREREQ: BIOL 209.  Alternate Spring semesters (2003, 2005, 2009).

Evolutionary Ecology - BIOL 614.  3 credits.  Evolutionary theory applied to ecological processes.  Topics  include: selection theory, ecological correlates of evolutionary forces, life-history theory, ecological genetics, coevolution. PREREQ: BIOL 209, 358, 417.  Alternate Fall semesters (Fall 2002, 2004, 2007, 2009)

<>Seminar in Floral Biology - BIOL 692 -  Reading and discussion of the primary literature in pollination biology and floral evolution.  Topics include genetic basis of floral variation, adaptive nature of floral traits, natural selection on floral form, floral gender dimorphism, coevolution and speciation. Occasional offering (Spring 2005 - with Paul Beardsley).

Phenotypic Evolution Seminar - BIOL 692 - Reading and discussion of the primary literature in morphological evolution and diversity, focusing on adaptation, definitions of fitness, multivariate selection, and speciation. Occasional offering (Spring 2005 - with Noah Anderson)

Darwin Seminar - BIOL 499/599 - A seminar for graduate students and advanced undergraduates to read and discuss Darwin's influential work. Occasional offering (On the Origin of Species - Spring 2006, Descent of Man and Selection in Relation to Sex - Fall 2008)

Ecology and Evolution of Flowers Seminar - BIOL 499/599 - Using Harder and Barrett's (2006) volume "Ecology and Evolution of Flowers" and the primary literature to explore recent theoretical and empirical advances in the field (Fall 2008)

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    INFORMATION FOR PROSPECTIVE STUDENTS:  Students interested in research in molecular ecology, plant reproductive ecology, and plant population genetics, evolution or systematics are welcome to contact me about the graduate program and potential research projects at ISU and RMBL.  I have been actively involved in training undergraduate and graduate students in research and teaching.  There are many opportunities for research at both the undergraduate and graduate levels in the Department of Biological Sciences at Idaho State University.  The department offers graduate training in the Master of Science, Ph.D. and Doctor of Arts (for students emphasizing college teaching) programs. There is funding available for both undergraduate and graduate research through the University Undergraduate and Graduate Research Committees, Teaching Assistanceships in the Department of Biological Sciences and the NSF funded GK-12 program.  Graduate students are encouraged to develop an independent research project and apply for external funding through State and Federal agencies, including the National Science Foundation.

GRADUATE STUDENTS:  Since moving to ISU I've worked with a number of M.S. and Ph.D. students as
    research advisor, graduate committee member, and mentor for Doctor of Arts (D.A.) teaching internships.
    Some of the students and projects are listed below:

Adjoa O. Ahedor (M.S. 2001).  Microsatellite analysis of a broad hybrid zone in the buckeye genus Aesculus L.
    (Hippcastanaceae). Major Advisor with Dr. Jenny Xiang.
Noah Anderson (D.A. candidate). Neurophysiology and evolution of feeding behaviors in turtles. Committee Member.
Janet Bala (M.S. 2007). Resource allocation and gender dimorphism in gynodioecious
  Major Advisor.

Sheel Bansal (Ph.D. candidate). Elevational effects on ecophysiology of Douglas Fir seedlings. Committee Member.
Kayce Bell (M.S. 2006). Phylogeographic history and population genetic structure of the Mojave Ground
    Squirrel, Spermophilus mohavensis. Committee Member.
Aren Eddingsaas (M.S. 2003). Phylogenetics of Arctic Ground Squirrels (Spermophilus parryii).

    Committee Member
Nancy Hampton (Ph.D. Candidate). Ecological dynamics of the sagebrush defoliator moth. Aroga websteri.
    Committee Member.
Guichan Hou (Ph.D. 2001).  Developmental and molecular genetic studies of the root in the fern Ceratopteris

    richardii. Committee Member.
Deborah Johnson (Ph.D. 2007). Evolution of the monosaccharide transporter gene family in land plants:
    phylogenetic analysis in a non-seed plant, Ceratopteris richardii. Committee Member
Chris Jenkins (Ph.D. 2007).  Distrubance effects on life histories of Great Basin Rattlesnakes (Crotalus viridus
    lutosus) in the upper Snake River Plain.  Committee Member.
Karen Kraus (M.S. Candidate). Effects of fire-induced hydrophobic soils on lodgepole pine regeneration.
    Major Advisor
Chang Liu (M.S. 2008). Systematics and character evolution in Myoporum. Committee Member.
Jennifer Merriam (D.A. 2002).  D.A. teaching internship in Ecology, BIOS 209.  Faculty Mentor.

Katie Miller (M.S. 2007). Population genetics and mating system of Townsend's Big-eared bats.
    Committee Member.
Erin Naegle (D.A. Candidate). Using tree-thinking to improve comprehension of biological concepts.
    Committee Member.
Sue Parsons (M.S. Candidate). Population structure of Great Basin Rattlesnakes. Committee Member.
Jill Petrisko (D.A. 2003). Molecular characterization and ecology of Saprolegnia and Achleya (Oomycota:

    Saprolegniaceae).  Committee Member.
Kira Pontius (M.S. 2007). Elevational effects on Nicrophorus life history traits. Committee Member.
Faith Rudebusch (M.S. 2008). Effects of introduced species on plant-pollinator interactions on an
    Aleutian island. Committee Member.
Amy Runck (Ph.D. 2006).  Hybridization and introgression between vole species in a contact zone.    
    Committee Member
Quinn Shurtliff (Ph.D. Candidate). Mechanisms of reproductive isolation in a Neotoma contact zone.
     Committee Member
Erik Tomasik (M.S. 2003).  Genetic and morphological variation in wolverine (Gulo gulo).

    Committee Member.
Eric Waltari (Ph.D. 2004).  Comparative phylogeography of Arctic Hares, Beringian Shrews, and their
    endoparasites.  Committee Member.
Byron Weckworth (M.S. 2003).  Biogeography and genetic analysis of South Alaskan Canis lupus.
    Committee Member.

UNDERGRADUATE RESEARCH STUDENTS:  I have worked with a large number of undergraduate research

    students, mostly at the Rocky Mountain Biological Laboratory and currently at ISU.  Many of these students
    have been involved in the Research Experience for Undergraduates (REU) program at RMBL. Many of these
    students have gone on to graduate schools in ecology, evolution, and genetics.  A partial list of students and
    their projects are below:

Carla Cortes Baez (2002).  Effect of sex ratio on pollen load and seed production in gynodioecious Geranium

    richardsonii.  RMBL-REU and University of Puerto Rico.
Penny Ciak (2002-03).  Pollinator community structure and pollination efficiency in the sage-steppe. Idaho
    State University.
Allison Drew (1997).  Pollinator choice of flower size and sexual morph in Geranium richardsonii. RMBL and
    Cornell University. (Currently in graduate school, UC-Berkeley).
Maria Garza (1996).  Distribution and habitat characterization of subalpine chiropteran species. RMBL and
    Texas A&M-Kingsville.
Amanda Gibson (2000).   The effect of plant size and local population structure on pollinator attraction in
    gynodioecious Geranium richardsonii (Geraniaceae). RMBL-REU and Drew University.  (Currently in
    graduate school,  University of Maryland).
Jonathan Godfrey (2001-02).  Developing chloroplast DNA markers to study gene flow and gender
    dimorphism in gynodioecious Geranium richardsonii.  Idaho State University. (Medical School)
Jeremy Green (2002).  Effects of phenology and density on pollination and the mating system in Delphinium
    nuttallianum.  NIH-BRIN Undergraduate Research Fellowship, Idaho State University. (teaches High School)
Sarah Harney (1996).  Correlation between insect abundance and foraging activity of the sub-alpine bats of
    Gothic, Colorado. RMBL and Nebraska Wesleyan University (attended graduate school, University of
Jennifer Howeth (2001).  Genetic structure within populations of Geranium richardsonii.  RMBL Research
    Internship. (currently in graduate school, University of Texas-Austin).
Steve Karrer (1996).  Gene flow and genetic structure among populations of Geranium richardsonii in
    Colorado. Nebraska Wesleyan University.
Jodi McKay (2001-2002).  Paternity analysis of burying beetles to determine alternative mating behaviors.
    Idaho State University.  (Attending graduate school in genetics, Iowa State University).
Kelly O’Malley (1998).  Estimation of selfing rate and inbreeding depression in gynodioecious Geranium
    richardsonii.  RMBL-REU and Saint John's College (M.S. from Duke University)
Maria Piantek (2001).  The effect of hermaphrodite density and frequency at three spatial scales on the pollen
    receipt and seed set of gynodioecious Geranium richardsonii (Geraniaceae).  RMBL-REU and Truman
    State University.
Martha Palomino Tovar (1999).  A comparison of reproductive effort between hermaphrodites and females of
    Geranium richardsonii: implications for maintenance of gynodioecy.  RMBL-Americas Scholarship and
    National Autonomous University of Mexico, UNAM.  (Attending graduate school in ecology, UC-Berkeley)
Jose Luis Ramirez (2001-02).  Paternity analysis of burying beetles to determine alternative mating behaviors.

    Idaho State University.  (attending graduate school in entomology at U-C Riverside)
Jessica Ruvinsky (1995).  Population genetic structure and the effect of the breeding system in Delphinium
    barbeyi.  RMBL and Yale University (Ph.D. from Stanford University)
Donald Sandmann (2002).  Effects of selfing and outcrossing on the maintenance of gynodioecy in wild
    geranium (Geranium richardsonii).  Idaho State University. (teaching High School biology/art)
Jay Storz (1994).  Summer population structure and habitat selection of subalpine bats near Gothic, Colorado.
    RMBL and University of Colorado. (Ph.D. from Boston University, Postdoc at University of Arizona).
Josh Sutherland (2005). Estimating clone size and diversity in Fireweed using AFLP.  Idaho State University.
Mariko Squires (2004).  AFLP variation in progeny arrays of Delphinium barbeyi. Idaho State University.
Mark Viera (1995).  Correlation of environmental parameters and insect abundance to bat foraging patterns.

    RMBL-REU.  (Attended graduate school, Colorado State University).
Jeff Wheeler (2001-02).  Developing chloroplast DNA markers to study gene flow and gender dimorphism in
    gynodioecious Geranium richardsonii.  Idaho State University. (attending Medical School)
Rachel Winston (2004).  Identification of intraspecific sequence variation in chloroplast DNA of Geranium        
    richardsonii.  Idaho State University (attending graduate school at University of Idaho).
Trent Wimmer (1996).  Gynodioecy in Brassica rapa and its effects on pollen production and petal size.

    Nebraska Wesleyan University.

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Downloadable .pdf versions of some of these papers are available by clicking on the links below.  If you need a
    copy of Acrobat Reader for your computer it can be downloaded for free at the Adobe Acrobat site.

Thomas, D.T., A.R. Ahedor, C.F. Williams, C. DePamphilis, D.J. Crawford, and Q.-Y. Xiang. 2008.
Genetic analysis of a broad hybrid zone in Aesculus (Sapindaceae) – Is there evidence of
long-distance pollen dispersal? International Journal of Plant Sciences 169(5):647-657.

Petrisko, J., C.A. Pearl, D.S. Pilliod, P.P. Sheridan, C.F. Williams, C.R. Peterson, and R.B. Bury. 2008.
identified on amphibian eggs throughout the Pacific Northwest, USA, by internal
transcribed spacer
sequences and phylogenetic analysis. Mycologia 100(2):171-180.

Williams, C.F. 2007. Effects of floral display size and biparental inbreeding on outcrossing rates in
    Delphinium barbeyi (Ranunculaceae). American Journal of Botany 94(10): 1696-1705.

Keeler, K. H., C. F. Williams, and L. S. Vescio.  2002.  Clone size of Andropogon gerardii Vitman (Big
    Bluestem) at Konza Prairie, Kansas.  American Midland Naturalist 147:295-304.

Williams, C. F., Ruvinsky, J., Scott, P. E., and D. K. Hews.  2001.  Pollination, breeding system, and genetic
    structure in two sympatric Delphinium  (Ranunculaceae) species.  American Journal of Botany  88(9):

Waser, N. M., and C. F. Williams.  2001.  Inbreeding and outbreeding.  Pp. 84-98 In C.W. Fox, D. A. Roff, and
    D. J. Fairburn (eds.), Evolutionary ecology: concepts and case studies.  Oxford Univ. Press, Oxford, UK.

Williams, C. F., M. A. Kuchenreuther, and A. Drew.  2000.  Floral dimorphism, pollinator attraction and
    self-fertilization in gynodioecious Geranium richardsonii. (Geraniaceae).  American Journal of Botany

Williams, C. F. and N. M. Waser.  1999.  Spatial genetic structure in Delphinium nuttallianum:  inferences
    about gene flow.  Heredity  83(5):541-550.

Storz, J. F., and C. F. Williams.  1996.  Summer population structure of subalpine bats in Colorado.
    Southwestern Naturalist 41(3):322-324.

Williams, C. F.  1994.  Genetic consequences of seed dispersal in three sympatric forest herbs.  II.
    Microspatial genetic structure within populations.  Evolution 48(6): 1959-1972. [Evol94b.pdf]

Williams, C. F. and R. P. Guries.  1994.  Genetic consequences of seed dispersal in three sympatric forest
    herbs.  I.  Hierarchical population genetic structure.  Evolution 48(3): 791-805. [Evol94a.pdf]

Fleming, T.H., and C.F. Williams.  1990.  Phenology, seed dispersal, and recruitment in Cecropia peltata
    (Cecropiaceae) in Costa Rican tropical dry forest.  J. Trop. Ecol.  6:163-178.

Mock, D.W., T. C. Lamey,  C.F. Williams, and A. Pelletier.  1987.  Flexibility in the development of heron sibling
    aggression: an intraspecific test of the prey-size hypothesis.  Anim. Behav.  35:1386-1393.

Williams, C.F.  1986.  Social organization of the bat, Carollia perspicillata (Chiroptera:  Phyllostomidae).
    Ethology 71:265-282.

Fleming, T.H., C.F. Williams, F.J. Bonaccorso, and L.H. Herbst.  1985.  Phenology, seed dispersal, and
    colonization in Muntingia calabura, a neotropical pioneer tree.  Amer. J. Botany 72:383-391.

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Curriculum Vitae

Download a .pdf version of my recent CV (updated August 2007)


1992/93   NSF Postdoctoral Fellow, University of California-Riverside and RMBL
                 Project Title:  Spatial genetic structure and genetic demography of Delphinium nelsonii.
                 Advisor:  Nickolas M. Waser
1991        Ph.D. in Botany, University of Wisconsin, Madison, WI.
                 Dissertation title:  Spatial genetic consequences of seed dispersal:  a comparative study of
                 three sympatric forest herbs (Umbelliferae).  Advisor:  Donald M. Waller
1985        M.S. in Biology, University of Miami, Coral Gables, FL.
                 Thesis title:  Social organization of the bat, Carollia perspicillata  (Chiroptera: Phyllostomidae).
                 Advisor:  Theodore H. Fleming
1979        B.S. in Zoology, University of Oklahoma, Norman, OK.


Ecology and evolution of gynodioecy, population genetic consequences of plant-animal interactions and dispersal, molecular population genetics, spatial genetic structure of plant populations, evolution of plant mating systems and co-evolution of plants and pollinators, ecology and genetics of invasive plants, pollination and seed dispersal biology, plant evolutionary ecology, ecology and behavior of bats, birds, and insects.


2008-present      Associate Professor, Department of Biological Sciences, Idaho State Univ.
                             Curator of Botany, Ray J. Davis Herbarium, Idaho Museum of Natural History
2001- 2008         Assistant Professor, Department of Biological Sciences, Idaho State Univ.;

                             General Genetics, Plant Systematics, Evolutionary Ecology, Plant-Animal Interactions
2000- 2002         Program Coordinator; NSF Research Experience for Undergraduates (REU) Site Grant;
                             Rocky Mountain Biological Laboratory
1999-2001          Research Assistant Professor, Department of Biological Sciences, Idaho State Univ.;
                             Molecular Methods in Ecology Seminar; General Ecology
1994-1998          Assistant Professor of Biology, Nebraska Wesleyan University; Introductory Botany,
                             Genetics, Evolution, Research Design, Natural History of Yucatan.
1993- present     Instructor, Field Ecology, Rocky Mountain Biological Laboratory (93-94),
                             Research Design and Analysis (96), supervised undergraduate independent research
                             students and REUs (93-04).


Botanical Society of America, Ecological Society of America, Society for the Study of Evolution, Sigma Xi.


Associate Editor: Evolution (2002-2004)

Reviewer for:  American Journal of Botany, American Naturalist, Australian J. Botany, Biotropica, Canadian Journal of Botany,
    Ecology, Ecology Letters, Evolution, Functional Ecology, Genetics, Heredity, Journal of Heredity, Journal of Tropical Ecology,
    Oecologia, The Prairie Naturalist, Trends in Ecology and Evolution, National Science Foundation

Rocky Mountain Biological Laboratory:
    Member of the Board of Trustees (two 5 year terms; 1996-2000, 2001-2005); Secretary (2001-2003).
    Service on numerous committees, including: Research Committee (1993-2001, Chair 1993-96),
    Land Protection Committee (Chair 1996-97), Curriculum Committee (1995-1997, 2000), Internal Review
    Committees (1996-98), Master Plan Revision Committee (1999-2000), Douglas Distinguished Lecturer
    Committee (1994-2004).

     Idaho State University – Department of Biological Sciences:
     Evolutionary Geneticist search committee (2001)
     Curriculum Review Committee (2002)
     Department Chair Search Committee (2003)
     Plant Biologist Search Committee (2003)
     Teaching Committee (2004-present)
     Facultly Sponsor for Biology Graduate Student Association (2003-present)
     Faculty Periodic Performance Review Committees (2004, 2006)
     Department Seminar Series Organizer (2007-present)

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Southeast Idaho and Southwest Colorado are pretty nice places to live and work!




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