Billie A. Gould
.
Graduate Student
Cornell University
Department of Ecology and Evolutionary Biology
.
.
Ecological Genetics of Rapid Evolution in Sweet Vernal Grass
In recent years two remarkable connections have been discovered between biological diversity at the molecular level and
Anthoxanthum odoratum
the functioning of ecosystems. First, genotypic diversity in dominant plant populations supports high levels of productivity and the ability to recover from disturbance. Second, directional evolution in plant populations can occur in response to human-mediated environmental change. Because rapid evolution of populations may entail substantial reduction of genotypic diversity due to natural selection, the effect of environmental change on genetic diversity may be an important aspect of how human activities affect ecosystems in the long term. To investigate this I am using comparative genetic analysis to examine how acidification of soils affects functional genetic diversity as well as gene flow in populations of a common wild plant, sweet vernal grass (Anthoxanthum odoratum). A. odoratum is introduced in the US, native to Europe, and has the ability to thrive in both basic as well as highly acidic soils. Early work on this species has suggested rapid evolution of populations in response to experimental as well as inadvertent anthropogenic alterations to soil pH and nutrient content. I am currently working with genotypes from the Park Grass Experiment at Rothamsted Research in Harpenden, UK; using next-generation sequencing to identify the mechanism of rapid evolution at this long-term ecological research site.
This work is done in collaboration with my PhD advisor Dr. Monica Geber and Dr. Susan McCouch at Cornell University.
.
Evidence of a high-Andean, mid-Holocene plant community: an ancient DNA analysis of glacially-preserved remains
Mat of ancient plant material
Throughout the Tropics, glaciers and ice caps are retreating at unprecedented rates due to global climate change. At several locations along the margin of the Quelccaya Ice Cap in southeastern Peru, remains of ancient plants previously covered by the ice have been continually uncovered since 2002. In collaboration with Blanca León, Aron M. Buffen, and Lonnie G. Thompson, I am using genetic analysis to identify these ancient plants. With continued global warming, studies of newly uncovered materials has the potential to reveal exciting details about the natural communities of the past.
Gould, Billie, Blanca León, Aron M. Buffen, Lonnie G. Thompson (2010) Evidence of a high-Andean, mid-Holocene plant community: an ancient DNA analysis of glacially-preserved remains. American Naturalist, 97: 9: 1579-1584
.
Virus-induced gene silencing as a tool for functional analyses in the emerging model plant Aquilegia (columbine, Ranunculaceae)
Partially silenced Aquilegia flower
The lower eudicot genus Aquilegia, commonly known as columbine, is currently the subject of extensive genetic and genomic research aimed at developing this taxon as a new model for the study of ecology and evolution. The ability to perform functional genetic analyses is a critical
component of this development process and ultimately has the potential to provide insight into the genetic basis for the evolution of a wide array of traits that differentiate flowering plants. Aquilegia is of particular interest due to both its recent evolutionary history, which involves a rapid adaptive radiation, and its intermediate phylogenetic position between core eudicot (e.g., Arabidopsis) and grass (e.g., Oryza) model species. In the lab of Elena Kramer (Harvard University), we demonstrated the effective use of a reverse genetic technique, virus-induced genesilencing (VIGS), to study gene function in this emerging model plant. This method can successfully be used to evaluate the function of early-acting developmental genes.
Gould, Billie and Elena Kramer (2007) Virus-induced gene silencing as a tool for functional analysis in the emerging model plant Aquilegia (columbine, Ranunculaceae). Plant Methods, 3:6
Kramer, Elena M., Lynn Holappa, Billie Gould, M. Alejandra Jamarillo, Dimitriy Setnikov, and Phillip M. Santiago (2007) Elaboration of B Gene Function to Include the Identity of Novel Floral Organs in the Lower Eudicot Aquilegia. Plant Cell, 19:750-766
