RESEARCH INTERESTS
I am broadly interested in plant evolution, including both phylogenetic perspectives on plant radiation and the effects of hybridization on evolution from the experimental to macroevolutionary scales.
Evolution of Non-flying Mammal Pollination in South African Protea
We just recently received funding from the NSF to study pollinator transitions in Protea! We will be expanding phylogenetic sampling of species and estimate the number of transitions to non-flying mammal pollinators (like rodents) and morphological and additional covariates assoicated with these transitions.
We just recently received funding from the NSF to study pollinator transitions in Protea! We will be expanding phylogenetic sampling of species and estimate the number of transitions to non-flying mammal pollinators (like rodents) and morphological and additional covariates assoicated with these transitions.
Helianthus giganteus
Patterns of Hybridization in Perennial Sunflowers in Wisconsin
There is historical documentation of hybridization between some of the perennial sunflower (Helianthus) species in the Upper Midwest, but do present-day populations have evidence for introgression? We are sampling three sunflower species (H. giganteus, H. grosseserratus, and H. maximiliani) across Wisconsin to assess both morphological and genetic diversity, funded in part by the UW - Eau Claire BCDT and the Milwaukee Public Museum Rundblad Fellowship. We are complementing our natural populations with measurements taken in two common gardens in Eau Claire and controlled greenhouse conditions to examine long-term dynamics of these individual species and their hybrids. We're in this for the long haul!
There is historical documentation of hybridization between some of the perennial sunflower (Helianthus) species in the Upper Midwest, but do present-day populations have evidence for introgression? We are sampling three sunflower species (H. giganteus, H. grosseserratus, and H. maximiliani) across Wisconsin to assess both morphological and genetic diversity, funded in part by the UW - Eau Claire BCDT and the Milwaukee Public Museum Rundblad Fellowship. We are complementing our natural populations with measurements taken in two common gardens in Eau Claire and controlled greenhouse conditions to examine long-term dynamics of these individual species and their hybrids. We're in this for the long haul!
Does Hybridization Speed Adaptive Evolution?
Hybridization is extremely prevalent in plants, but the extent to which hybridization contributes to evolutionary outcomes remains debated. We are using an eight-year field evolutionary experiment in with resynthesized Helianthus hybrids to understand the repeatability of hybridization across space and time and how hybrids may actually evolve faster than non-hybrid controls. Hybrids between H. annuus and H. debilis form the natural hybrid subspecies H. annuus ssp. texanus. Check out the first results in Scientific Reports! We further explore the repeatability of this system in multiple locations in this publication out in Evolution.
Hybridization is extremely prevalent in plants, but the extent to which hybridization contributes to evolutionary outcomes remains debated. We are using an eight-year field evolutionary experiment in with resynthesized Helianthus hybrids to understand the repeatability of hybridization across space and time and how hybrids may actually evolve faster than non-hybrid controls. Hybrids between H. annuus and H. debilis form the natural hybrid subspecies H. annuus ssp. texanus. Check out the first results in Scientific Reports! We further explore the repeatability of this system in multiple locations in this publication out in Evolution.
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Macroevolutionary Patterns of Hybridization in Plants
Hybridization is rampant in plants, but the prevalence of hybridization also varies across (and within) taxonomic groups. We explore correlates of hybridization in vascular plants and find that increased hybridization rates are association with factors that likely affect both the persistence of hybrids (like perenniality) and the formation of hybrids (outcrossing, pollination syndromes) in this publication in Evolution Letters. We also find some evidence for a positive association between hybridization rates and evolutionary diversification rates across seed plants (published in Evolution). Collaborative Work: PopUp Poplar Network We are also involved in a large collaborative project looking at hybridization and climate adaptation in poplars, together with a total of 19 different common gardens across the United States. Check out the PopUp Poplar Network site. |
Hybridization and diversification rates across seed plant families
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I completed my Ph.D. at the University of Connecticut working on an NSF-funded Dimensions of Biodiversity project investigating plant diversity in the Cape Floristic Region of South Africa. My research focuses on the genus Protea, specifically on its phylogenetic history and the role of the environment is shaping functional trait evolution. You can check out my dissertation on Digital Commons here!
Protea sulphurea
Trait-Environment Associations in Parallel Evolutionary Radiations
The Cape Floristic Region (CFR) of South Africa is a biodiversity hotspot containing >9,000 plant species, many of which are endemic. This incredible diversity is dominated in just a few plant lineages which are both speciose and morphologically diverse. In addition, the CFR is a complex environment characterized by multiple gradients in temperature and rainfall amount and seasonality, as well as topographical compexity, edaphic heterogeneity, and differing fire regimes. If the CFR's complicated environment has driven the evolution of plant form, we expect to see associations between functional traits and the environments in which they occur. We extensively sampled two iconic, yet drastically different, CFR lineages, Protea and Pelargonium, across a single biome for multiple plant traits of significance. We use a detailed Bayesian analysis to compare and contrast detectable associations, and find both generalizable pattens and distinct, lineage-specific trends. Global patterns do not always hold up at the scale of the biome, but trends are indicative of parallel responses to similar climatic pressures.
The Role of Climate in Driving Protea Diversification
Another portion of my research focuses on the phylogenetic history of the genus Protea (Proteaceae), which is composed of ~112 species, most of which are found in the CFR. Together with the Lemmon lab at Florida State University, I employed an "Anchored Phylogenomics" approach to fully resolve the Protea phylogeny. This method uses a target-capture approach to obtain sequences for 300 nuclear loci conserved across all angiosperms. This detailed technique was necessary, given Protea's fairly recent, rapid radiation (crown age of 5-18my). I used this well-resolved phylogeny to answer detailed questions about the drivers of Protea diversification and patterns of trait and climatic niche evolution.
Seedling Protea punctata and Protea venusta in the UConn greenhouse.
Mechanistic Trait Relationships in a Protea Hybrid Zone
Our findings across genera show a breakdown between global patterns and those within a single biome in two focal clades. I am using the increased trait variation in a natural hybrid zone between Protea punctata and P. venusta to examine trait and microclimate differentiation along a steep elevational gradient in the field. I am also using wild-collected seeds to examine seedling stress response differences in the greenhouse. NSF DDIG funding allowed me to genetically differentiate introgression patterns along the cline using thousands of SNPs discovered using RADseq and in the future I hope to compare these to transcriptomic (RNAseq) data. These data will also be used to uncover the genetic architecture of complex functional traits.
Our findings across genera show a breakdown between global patterns and those within a single biome in two focal clades. I am using the increased trait variation in a natural hybrid zone between Protea punctata and P. venusta to examine trait and microclimate differentiation along a steep elevational gradient in the field. I am also using wild-collected seeds to examine seedling stress response differences in the greenhouse. NSF DDIG funding allowed me to genetically differentiate introgression patterns along the cline using thousands of SNPs discovered using RADseq and in the future I hope to compare these to transcriptomic (RNAseq) data. These data will also be used to uncover the genetic architecture of complex functional traits.
Isle Royale National Park, MI
Former Research
I received my undergraduate degree in biology from Williams College, where I worked on several projects under the tutelage of Dr. Joan Edwards, including:
I received my undergraduate degree in biology from Williams College, where I worked on several projects under the tutelage of Dr. Joan Edwards, including:
- impacts of invasive garlic mustard (Alliaria petiolata) on native New England plant species
- pollination networks surrounding bunchberry dogwood (Cornus canadensis) in Isle Royale National Park
- long-term studies on Great Lakes-Arctic disjunct plants
- spore dispersal in Sphagnum moss: technical work
- honors thesis on high-speed movements in plants (Impatiens pallida, Oxalis, Medicago sativa)
External Funding:
- 2023-2025: NSF BRC-BIO Grant: "Understanding the Role of Species Interactions in Evolutionary Radiations Through the Evolution of Non-flying Mammal Pollination in the Iconic Plant Genus Protea" ($294,395)
- 2020: Milwaukee Public Museum Rundblad Fellowship: "Historical and contemporary patterns of hybridization in perennial sunflowers of Wisconsin." ($12,000)
- 2016: NSF Evolutionary Genetics Program Doctoral Dissertation Improvement Grant: “Dissertation research: Are functional traits adaptive? Dissecting the evolutionary dynamics of plant functional traits” ($17,928)
- 2015: Botanical Society of America Graduate Student Research Award “Using natural hybrids to investigate trait-environment associations and stress response in an evolutionary radiation” ($500)
