Sunday, August 10, 2008
Wednesday, November 29, 2006

New places that I work...
Pennsylvania and Maryland serpentine barrens, where a number of regionally rare species grow alongside a group of more tolerant species. Many of the species that can tolerate these soils with extremely low Ca:Mg and high levels of Nickel and Chromium also grow on other disturbed or extreme soils that occur in the region.
Tuesday, November 28, 2006
The overarching goal of my research is to understand adaptive evolution from mechanisms to landscapes. In this era of increased biological homogenization, where human activities have greatly reduced the uniqueness of local floras and faunas through species introductions and extirpations, it is essential to understand the processes that lead to the formation of locally differentiated forms if we are to successfully steward rare species, restore populations of species lost to landuse change, or manage invasive species spreading to new areas. To understand how locally differentiated forms arise, it is essential to understand how genotypes become phenotypes, as local differentiation can arise from both genetic and environmental differences.
To better understand how locally differentiated forms arise, I use two broad sets of complementary approaches that focus on genetic, developmental, and physiological mechanisms of differentiation, and landscape patterns of variation. Furthermore, I use in tandem two sets of focal organisms: emerging genetic model organisms in which it is possible to perform manipulative studies, and the rare and declining or invasive species that are most in need of management attention.
Population differentiation in fragmented landscapes
In my dissertation research I examined the mechanisms and landscape patterns of population differentiation in phenotypically plastic shade avoidance elongation in Impatiens capensis, a North American native annual which has become invasive in Europe. Forest understory populations of I. capensis have been observed to elongate less in response to reduced ratios of red:far red (R:FR) light, an important signal of foliage shade, than conspecific plants from open canopy sites. To determine whether the observed pattern of differentiation occurs consistently, I collected seedlings from five pairs of open and closed canopy habitats to determine if the pattern of differentiation is consistent across populations (1). By growing the progeny of the seedlings under two shade treatments to simulate responses to open and closed canopy sites, I was able to determine that populations differed between open and closed canopy sites, but that open canopy plants do not always respond more to shade than plants from open canopy sites. Furthermore, by developing AFLP molecular markers, I showed that this differentiation occurs despite extensive gene flow, and that the differentiation between habitats in morphological traits (Qst) is greater than expected from the marker based Fst. These results suggest that differentiating selection consistently acts on I. capensis between open and closed habitats over short spatial and temporal scales, but that the endpoints of this selection will differ depending on starting genetic variation, correlated features of different specific habitats, and the length of time over which differentiation occurs.
Reduced responsiveness to low R:FR in plants from closed canopy sites could be caused by two physiological mechanisms. First, closed canopy plants could have less sensitive “shade avoidance” elongation responses to low R:FR. Secondly, the high irradiance response to FR (FR-HIR), which allows seedlings to stop elongating out of the soil (ie, de-etiolating) under low R:FR, might persist longer in closed-canopy plants, counteracting shade avoidance responses to low R:FR in juvenile plants. I tested these hypotheses by using red and far-red light emitting diodes to distinguish the responses to altered R:FR of genotypes of I. capensis collected from a pair of open and closed canopy populations that differ in sensitivity to R:FR (2). Genotypes from the open site exhibited typical shade avoidance responses, elongating in response to supplemental FR. However, genotypes from the closed canopy site responded to supplemental FR by elongating less than under ambient control conditions, indicating a persistent FR-HIR. Thus, in a single focal pair of populations the observed population differentiation in response to low R:FR may be linked to differences in FR-HIR.
For more information on my work on shade avoidance in Impatiens, see (3), (4), and (5). I am continuing collaborative work on the relationship of flowering time and elongation with Kathleen Donohue and Annie Schmitt in the US, and work on the biomechanics of elongation and mechanical stimulation with Heidi Huber and Niels Anten at Nijmegan and Utrecht Universities in the Netherlands.
Invasion and Conservation Genetics
As popular ornamentals, many Impatiens species have been transported to new regions for their floral displays, and have subsequently spread from cultivation. In work mentoring Brown undergraduates, we have examined the dispersal behavior of two invasive Impatiens species (6) and the climate envelope of African ornamental Impatiens (7). I am reviewing this work and related work on Impatiens invasions with Nava Tabak at the University of Connecticut (8).
Grasslands currently cover a small portion of coastal New England, but host a large number of regionally rare species. I worked with Kelly Gravuer, now a botanist at NatureServe, to examine patterns of population differentiation in Liatris scariosa var. Novae Angliae, a rare New England grassland composite. Liatris is found in many coastal grasslands from New York to Maine. These populations differ greatly in size, in management strategy, and in surrounding landscape. In a greenhouse common garden, we found that populations differed in leaf traits more than expected by allozyme differentiation, implying that selection on leaf shape favors shorter leaves in populations that are regularly mowed compared to those that are burned or unmanaged (9). These results suggest that translocation and augmentation schemes should consider manage-ment history as well as genetic relatedness in choosing source populations. I am currently using similar methods to guide efforts by the Nantucket Conservation Foundation to bolster populations of Aster concolor, another declining grassland composite. For other work with Liatris, see (10) and (11).
Landscape genomics of endemism and stress tolerance
In my postdoctoral research, I am using emerging genomic tools to examine how extreme soils such as serpentinic soils can drive local differentiation between populations. Serpentinic soils, which occur globally in small patches along fault lines, are extreme in having low Ca:Mg and high concentrations of nickel and other heavy metals, and host communities of regionally rare plants that are frequently threatened by development, mining, and invasive species. It is impossible to make informed management decisions about serpentinic areas without knowledge of the mechanisms by which serpentinic soils are tolerated and how tolerance evolves. If tolerance is achieved easily and can evolve quickly in any one species, it is feasible for plants from nearby non-serpentinic sites to establish on serpentinic areas. Conversely, if tolerance can only be achieved with difficulty and evolves infrequently in any one species, only plants from another serpentinic area are likely to establish on a particular serpentinic outcropping.
As genomic tools are required to fully characterize tolerance, I am developing Arabidopsis lyrata, a near relative of the model plant A. thaliana with an ongoing genome project, as an ecological model for serpentinic tolerance. In eastern North America A. lyrata naturally occurs on both serpentine soils with low Ca:Mg and high Ni levels as well as less extreme soils. The genetic underpinnings of tolerance of these soils are currently not understood, but as A. thaliana and A. lyrata genomic tools mature, the potential to use these tools in related species that naturally occur on these soils grows. I take a multi-pronged approach to the study of tolerance of these soils that uses a mix of 1) historic herbaria records and landcover data to characterize how soil types and landuse change have impacted the persistence of A. lyrata in the area between Philadelphia and Baltimore where there are “islands” of serpentic soil, 2) phenotypic characterization of differences in serpentine and non-serpentine populations in Ni and Ca:Mg tolerance both under controlled hydroponic and field conditions, and 3) emerging genomic tools to find candidate pathways and genes for tolerance of Ni and low Ca:Mg.
As the potential to take genomic resources from model organisms to related non-model organisms grows, I intend to also work on salinity tolerance in salt marsh grasses and in relatives of alfalfa. Alterations to water salinity is a significant contributor to degradation of many coastal plant communities, and salinization of agricultural soils is a major challenge to crop yields in arid regions. I am currently working with the groups of Brian Silliman and Mark Bertness to characterize differential effects of increased salinity on the competitive ability of native North American and exotic Eurasian ecotypes of Phragmites australis. There are already substantial genomic resources for rice; as all grass genomes are largely co-linear, it will be possible to extend these tools to other grasses. Similarly, I am beginning work on salinity tolerance among Tunisian ecotypes of Medicago truncatula, a relative of the crop alfalfa for which a genome sequence is nearly complete.
Future research goals
As a faculty member, I intend to maintain a research program that uses interdisciplinary approaches to characterize mechanisms and landscape patterns of tolerance to extreme soils, both naturally occurring and human created. My goals are to increase our knowledge of how tolerance is achieved so that tolerance can be improved in 1) plants that we maintain economically, as well as 2) provide information necessary to maintain and restore the populations of rare species that can naturally tolerate these soils, and 3) to prevent unwanted species from spreading. I will continue to use both emerging genetic model species and rare or noxious species for which management information is needed.
1. E. J. Von Wettberg, D. L. Remington, J. Schmitt, Am. Nat. (in review).
2. E. J. von Wettberg, J. Schmitt, Am. J. Bot. 92, 868 (May, 2005).
3. E. J. von Wettberg, H. Huber, J. Schmitt, Evolutionary Ecology Research 7, 531 (May, 2005).
4. H. Huber et al., Am. Nat. 163, 548 (Apr, 2004).
5. E. J. von Wettberg, J. Schmitt, Evolution (in review).
6. D. Auyeung, E. J. Von Wettberg, J. Schmitt, Plant Ecol. (in review).
7. L. A. Mandle, E. J. von Wettberg, M. Hoffman, J. Schmitt, Proc Natl Acad Sci U S A (in review).
8. N. M. Tabak, E. J. von Wettberg, (in preparation).
9. K. Gravuer, E. J. von Wettberg, J. Schmitt, Biological Conservation 124, 155 (2005).
10. K. Gravuer, E. J. von Wettberg, J. Schmitt, Am. J. Bot. 90, 1159 (2003).
11. M. Vadeboncoeur, E. J. von Wettberg, J. Schmitt, (in preparation).
Understanding how information is created and evaluated in Biology is as important as knowing the information itself because information turns over so rapidly. Learning to ask and answer questions, focusing on what we know and don’t know, and how we can learn about it, is essential in teaching and applying knowledge in Biology. I strive as a teacher to create an environment in which engagement with factual material, critical thinking, and clear communication skills are expected and rewarded.
In my teaching and mentoring I have two overarching goals. First, I want students to leave my courses with an understanding of how research creates knowledge in Organismal Biology. I think it is particularly important for students to have an understanding of how we know things in an era when biological information is critical to discussions of a range of important and contentious social issues. Second, I want my students to have the skills to gather, synthesize and explain new information to both their peers and to those without scientific backgrounds. Students who don’t go on in Biology need basic skills to understand developing knowledge created in Biology, and those who go on in Biology have a responsibility to explain their knowledge to others.
II. MENTORING STUDENTS
An essential component of the teaching performed by all faculty members is mentoring undergraduates, graduate students, and post-doctoral researchers. My mentoring approach is based on the mentoring I received as an undergraduate, research fellow, naturalist, and graduate student, and my experience in mentoring six undergraduate honors thesis projects while a graduate student at Brown.
Most importantly, I expect students to develop their own interests and intellectual independence. I work with students to pursue topics that interest them in ecology and evolutionary biology, rather then restrict them to work on my own research. I will keep multiple research projects in my lab, spanning a range from emerging model organisms to conservation projects with species of concern, so that students can find projects that fit their interests, and so that resources and approaches developed for one system can be applied to another. When students have research interests close to my own, I will insist that they develop the work’s conceptual novelty, methods, importance, and implementation. I will strive to encourage creativity by both challenging students to think broadly and supporting students by providing the attention and help they require.
As a mentor, I will strive to create a cohesive and collegial intellectual community in the lab, where students take an interest in each others work, collaborate on research projects, help each other with data collection, analysis, and writing, brainstorm about research plans, and provide feedback and criticism. I will work with students to think broadly about their interests, referring them to both current literature and classic literature from Darwin on. I strive to give quick and thoughtful feedback on experimental design, proposals, and manuscripts, as well as actively reading emerging literature with my students.
III. COURSES
My teaching practice is reflective and adaptable. My courses will begin with gaining an understanding of where students are coming from and what they expect to get from my courses. By using concept maps, short writing and discussion I will begin a dialogue with my students to shade both my expectations for courses and theirs. Throughout my courses I will use a variety of media for presentation and a variety of evaluation methods to meet the needs and talents of students. I will use regular assessment, polling and questioning to see if it is working, and adjust my approach from the results. Grades are used to measure my performance as well as that of students.
There will be a heavy emphasis on research in all of my courses, because it is how we learn things in Biology. I was introduced to the primary literature early in my undergraduate career, and I will use it, in addition to classic papers and secondary materials like textbooks. Writing assignments in my courses will emphasize how primary literature is created by expecting students to write in the tradition of research articles, literature reviews, and grant proposals. In addition to presenting their own research in writing, my courses will give students the opportunity to present their results to their peers at the end of a course. During courses I will also use problem sets and short writing to test and challenge mastery and employment of material.
Specific courses:
I am able to teach graduate and upper level courses in quantitative genetics and the evolution of complex traits, plant development and evolution, conservation genetics, invasion biology, geobotany, and landscape genetics. I have experience as a teaching assistant for courses in evolution, ecology, botany, entomology, and introductory biology. I can teach a variety of other courses depending on department needs.
For a more complete insight into my teaching, a teaching portfolio is available upon request.
Ecology and Evolution
Box G-W, 80 Waterman Street
Brown University
Providence, RI 02912
401-863-2619 (Office)
Email: Eric(underscore)von(underscore)Wettberg(at)Brown(dot)edu
Webpage: http://www.brown.edu/
Departments/EEB/graduate/evw.htm
Blog: http://
ericvonwettberg.blogspot.com
EDUCATION
Ph.D. Ecology and Evolution December 2006
Brown University, Providence, RI
• Dissertation Advisor: Prof. Johanna Schmitt
• Dissertation Title: Landscape genetics and local adaptation in Impatiens capensis
Fulbright Fellow and Rotary Ambassorial Scholar 1999-2000
Royal Veterinary and Agricultural University, Copenhagen, Denmark
• Advisor: Dr. Jacob Weiner
• Project title: Using crop density and spatial planting pattern to suppress weeds in organic cereal crops
B.A. Biology May 1999
Swarthmore College, Swarthmore, PA
• Graduated Phi Beta Kappa, Sigma Xi
RESEARCH
Interests
• Repeated evolution of local adaptation to landscape features and disturbance regimes, such as extreme soil types, degraded agricultural lands, overhead canopy in forest understory plants, and burning and mowing regimes in grasslands
• Correlated evolution of traits, such as drought and extreme soil tolerance, and seedling etiolation and shade avoidance elongation
• Effects of spatial patterns of environmental factors and dispersal on local adaptation and population connectivity in common, rare and invasive plants
Grants, Awards, Honors and Fellowships
• NIH National Research Service Award 2007-2010
Genomics of Nickel tolerance in Arabaidopsis lyrata
• NSF Doctoral Dissertation Improvement Grant 2004
Local adaptation and landscape genetics of plastic shade avoidance responses in Impatiens capensis
• EPA STAR Graduate Fellowship 2004-2007
Landscape genetics of escaped ornamental Impatiens
• SICB Graduate Student Travel Award 2004
For travel to the UK to collect introduced invasive genotypes of North American Impatiens capensis
• Nature Conservancy Wald Grant 2002
For study of conservation genetics of Liatris scariosa var. Novae-Angliae, a rare New England grassland perennial, with Kelly Gravuer and Johanna Schmitt
• Sigma Xi Grant in Aid of Research 2001-2004
For study of temporal change in allocation to dispersal structures in seeds of Liatris scariosa var. Novae-Angliae
• DoD Graduate Research Fellowship Finalist 2001
• Lande Summer Research Award, Swarthmore College 1997, 1998
For summer research on social behavior in halictid bees in Lakonia, Greece, and Rocky Mountain Biological Laboratory, Colorado, USA
PUBLICATIONS AND PRESENTATIONS
Peer Reviewed Journal Articles
von Wettberg, E.J. and Weiner, J. 2003. Nutrient heterogeneity does not make belowground competition size-asymmetric in glasshouse populations of Triticum aestivum. Plant Ecology. 169: 85-92.
Richards, M. H. von Wettberg, E.J. and Rutgers A. 2003. A novel social polymorphism in a primitively eusocial Hymenopteran. Proceedings of the National Academy of Science USA, 100: 7175-7180.
* Gravuer, K. von Wettberg, E.J. and Schmitt, J. 2003. Dispersal biology of Liatris scariosa var. novae-angliae (Asteraceae), a rare New England grassland perennial. American Journal of Botany. 90: 1159-1167. * Undergraduate mentored publication
von Wettberg, E.J. and Weiner, J. 2004. Effects of distance to crop rows and to conspecific neighbours on the Size of Brassica napus and Veronica persica weeds. Basic and Applied Ecology, 5: 34-41.
Huber, H. Kane, N. Heschel, M.S. von Wettberg, E.J. Banta, J. Leuck A. and Schmitt, J. 2004. Frequency and microenvironmental pattern of selection on plastic shade avoidance traits in a natural population of Impatiens capensis. American Naturalist, 163: 548-563.
* Gravuer, K. von Wettberg, E.J. and Schmitt, J. 2005. Population differentiation and genetic variation inform translocation decisions for Liatris scariosa var. novae-angliae, a rare New England grassland perennial. Biological Conservation, 124: 155-167. * Undergraduate mentored publication
von Wettberg, E.J. and Schmitt, J. 2005. An experimental separation of stem and leaf shade avoidance responses in Impatiens capensis. American Journal of Botany, 92: 868-874.
von Wettberg, E.J. Huber, H. and Schmitt, J. 2005. Interacting effects of microsite quality, plasticity, and dispersal distance from the parental site on fitness in a natural population of Impatiens capensis. Evolutionary Ecology Research. 7: 531-548.
Articles in review and preparation
* Auyeung, D. von Wettberg, E.J. and Schmitt, J. Implications of dispersal mechanisms for invasion across eustuarine bodies. Plant Ecology, in review. * Undergraduate mentored publication
von Wettberg, E.J. Remington, D.L. and Schmitt, J. Replicated population differentiation in plasticity? Shade avoidance in Impatiens capensis. American Naturalist, in review.
* Mandle, L., von Wettberg, E.J. Hoffman, M. and Schmitt, J. Escape from a climate cage? The naturalization of ornamental Impatiens walleriana in an expanded climate range. Proceedings of the National Academy of Science, in review. * Undergraduate mentored publication
von Wettberg, E.J. and Schmitt, J. Is there a correlation between different phytochrome-mediated plasticities? Evolution, in review.
Huber, H., von Wettberg, E.J., and Schmitt, J. Contextual advantages of R:FR induced elongation. In preparation, target journal: American Naturalist.
Tabak, N., and von Wettberg, E.J., Native and introduced Impatiens of the Northeast: parallel introductions and global spread of temperate jewelweeds. In Preparation, target journal: Northeastern Naturalist.
von Wettberg, E.J. Whittal J.B., Strauss S.Y., Stanton, M.L., and Nuzhdin, S.V. Genome-wide screen of differentiation in serpentinic and non-serpentinic Streptanthus polygaloides. In preparation, target journal Genetics
von Wettberg, E.J., Donohue, K., and Schmitt, J. Genetic correlation of elongation responses to light quality and quantity in Impatiens capensis. In preparation, target journal American Naturalist
Natural History and Educational Materials
von Wettberg, E.J. 2004. Transvestism of the Land. Watersheds. 2: 24-26.
von Wettberg, E.J. 2001. Muskrat Ramble. The New York State Conservationist 56: 8-10.
von Wettberg, E.J. 2001. A Guided Tour of the Madison Lane Wetland. A pamphlet printed by the Madison Lane Landtrust, Hamilton, N.Y., USA.
Selected Invited Seminars
Population differentiation in shade avoidance responses in Impatiens capensis. Ecological Society of America/Intercol proposed symposium, Montreal, Canada, 2005.
What we wish we knew as undergraduates. Evolution Meeting, Fairbanks, Alaska, 2005. Co-presented with Dr. Johanna Schmitt.
Shade avoidance and high irradiance responses in Impatiens capensis, Utrecht University, the Netherlands, 2004.
Size symmetric below ground competition in wheat for heterogenously distributed
nutrients, Danish Agricultural Research Station, Foulum, Denmark, 2000.
TEACHING
Teaching Assistant
• Ecology, Ecology and Evolution, Brown University Spring 2004
• Seed Plant Diversity, Ecology and Evolution, Brown University Fall 2002, 2003
• Insect Biology, Ecology and Evolution, Brown University Spring 2002
• Evolution, Ecology and Evolution, Brown University Fall 2001
• Introductory Biology, Biology Department, Swarthmore College 1997-1998
Natural History Teaching
• Naturalist Intern, New York State DEM Spring 2001
Guest Lectures
• Seed Plant Diversity, Ecology and Evolution, Brown University Fall 2002-2004
• Conservation Biology, Ecology and Evolution, Brown University Fall 2005
Pedagogical Training
• Teaching Certificate Program I-III May 2003-2006
The Harriet W. Sheridan Center for Teaching and Learning, Brown University
• Writing Associate 1997-1998
Writing Program, Swarthmore College
Mentored Undergraduate students
• Christine Holdredge B. Sc, Biology, Brown University. 2007 “Salinity affects competition between native and exotic Phragmites australis”
• Lisa Mandle, B. Sc, Biology, Brown University, Dec 2006 “Climate and propagule pressure do not explain naturalization success and failure of the widely planted ornamental Impatiens walleriana.”
• Novem Auyeung, B.Sc Environmental Studies, Brown University. 2005 "Pathway from Ornamentals to Invasives: A Case Study of Impatiens."
• Lauren McGeoch, B.Sc. Environmental Studies, Brown University. 2004 “Mondia harvests in Kenyan national forests”
• Matt Vadebonceour, B.Sc. Environmental Studies, Brown University. 2003 “GIS approach to picking suitable patches for matepopulation conservation.”
• Kelly Gravuer, B. Sc. Biology, Brown University. 2002 “Population differentiation in Liatris scariosa var. Novae Angliae: Implications for management.”
PROFESSIONAL ACTIVITIES AND COMMITTEES
Reviewer: Biological Conservation (2006), Canadian Journal of Botany (2006), Plant Biology (2006), American Journal of Botany (2005), Plant Ecology (2005), New Phytologist (2004-2005), Biology Letters, Royal Society (2004); Oecologia (2004); Ecological Applications (2003); Clonal plant workshop, Evolutionary Ecology (2000).
Member: American Society of Naturalists, Botanical Society of America, Society for the Study of Evolution, Ecological Society of America, Rhode Island Natural History Survey, New England Botanical Club, New England Society for Conservation Biology.
RI Invasive Species Council 2005-2006
Participated in updating of the invasive species watch list for Rhode Island.
RI Plant Conservation Task Force 2002-2006
Prioritized species for conservation efforts and assist with surveys of rare species populations in Rhode Island.
New England Invasive Plant Atlas Survey 2002-2005
Monitored Providence and Block Island for invasive plant species.
EEB Department Graduate Teaching Liaison 2003-2004
Sheridan Center for Teaching in Higher Education, Brown University
Science Teaching Consultant 2003-2006
Sheridan Center for Teaching in Higher Education, Brown University
Career Services Panelist 2005
How to Succeed in Graduate School, Career Services, Brown University
Alumni Panelist 2004
Biology Department Graduate School Night, Swarthmore College
Environmental Change Initiative Chair Search Committee 2004
Graduate Student representative, Environmental Studies, Brown University
Sierra Club Committee on Genetically Modified Organisms 2006
Corresponding member
FACULTY AND STUDENT REFERENCES AVAILABLE ON REQUEST
Tuesday, May 02, 2006
Research Rationale
We live in an age of increasing biological and cultural globalization that has been dubbed the "homogocene." Two of the greatest biological threats we face today are the loss of rare species and the invasion of new areas by exotic species. As species losses and biological invasions continue, the world becomes both more homogenous and more biologically depauperate.
The formation of local variants has long fascinated naturalists and biologists, and has been a central focus of evolutionary study since the field's conception. In the face of homogenization, the study of the patterns and processes by which organisms take on unique local forms takes on an increased importance, as it sheds light on how rare species become rare and how introduced species adapt to new locations.
Furthermore, the homogenization of the world's biota has been accompanied by the fragmentation of nearly every terrestrial habitat. For species with meta-population dynamics, dispersal across habitat barriers may make dispersal from similar habitats less frequent, and local adaptation more important for the persistence of species.
The extent to which organisms become locally adapted to habitats depends on the interplay of the degree to which habitats vary in important variables that impact fitness, the ability of organisms to respond plastically the environmental variables to produce appropriate phenotypes for the environment, and dispersal between the habitats. In my research I use a range of tools to look at the roles of dispersal, phenotypic plasticity, environmental patterning of macronutrients, and correlations among traits, as well as niche breadth and gene duplications in creating, maintaining, and disrupting unique local forms, or ecotypes.
On this site I have placed links to my research interests, teaching, and professional and volunteer activities.
I am an ecological geneticist, botanist, population biologist, evolutionary biologist, etc, broadly interested in the broad field of ecology, evolution, and conservation biology.
You can view my current website, from my graduate work, at Brown University
http://www.brown.edu/Departments/EEB/graduate/evw.htm
