Krissa Skogen, Ph.D.
CV Ph.D. University of Connecticut, 2008 B.A. Gustavus Adolphus College, 2000 Associate Professor - Clemson University 132 Long Hall Clemson University Clemson, SC 29634 kskogen[at]clemson.edu Adjunct Professor - Northwestern University |
CURRENT LAB MEMBERS

Dylan Cohen, Ph.D. Postdoctoral Researcher
I am an evolutionary biologist with interests in conservation genetics, systematics, historical biogeography, plant-pollinator interactions, and plant adaptations to arid and alpine environments. I received my PhD in May of 2021 from Claremont Graduate University/California Botanic Garden. My dissertation focused on the evolution and ecology of several groups from Loasaceae. The first chapter dealt with conservation implications for Mentzelia polita, a rare and threatened species with a limited distribution in Mojave Desert. In my second and third chapters, I studied several genera distributed across the Southern Cone of South America. I used phylogenomic analyses to resolve relationships in the Southern Andean Loasa clade, reconstructed historical biogeography, and inferred diversification rates across the central and southern Andes. My last chapter investigated species relationships for Pinnasa and the impacts of recent glaciation to population structure across Pinnasa pinnatifida. At Chicago Botanic Garden I work on the conservation genetics of a rare and threatened plant, Amsonia tharpii. This species has five populations and is under threat due to expansion of oil and gas well development in southeastern New Mexico. Results from this study will assist Fish and Wildlife in determining if A. tharpii should be listed under the Endangered Species Act.
I am an evolutionary biologist with interests in conservation genetics, systematics, historical biogeography, plant-pollinator interactions, and plant adaptations to arid and alpine environments. I received my PhD in May of 2021 from Claremont Graduate University/California Botanic Garden. My dissertation focused on the evolution and ecology of several groups from Loasaceae. The first chapter dealt with conservation implications for Mentzelia polita, a rare and threatened species with a limited distribution in Mojave Desert. In my second and third chapters, I studied several genera distributed across the Southern Cone of South America. I used phylogenomic analyses to resolve relationships in the Southern Andean Loasa clade, reconstructed historical biogeography, and inferred diversification rates across the central and southern Andes. My last chapter investigated species relationships for Pinnasa and the impacts of recent glaciation to population structure across Pinnasa pinnatifida. At Chicago Botanic Garden I work on the conservation genetics of a rare and threatened plant, Amsonia tharpii. This species has five populations and is under threat due to expansion of oil and gas well development in southeastern New Mexico. Results from this study will assist Fish and Wildlife in determining if A. tharpii should be listed under the Endangered Species Act.

Haley Carter, Ph.D. Expected 2024
Plant Biology and Conservation Program - NU/CBG
Co-Advised with Norm Wickett
After graduating with a BS in Biology from Brown University in 2017 and working as a research assistant for the Conservation and Land Management Program and the Landscapes of Linalool project in the Skogen Lab, I started graduate school as a Masters student with Dr Skogen in 2019. I have since transitioned to the PhD program and am primarily advised by Dr Wickett but continue to work closely with the Skogen Lab as my graduate research builds off their previous work. I am broadly interested in the evolution of secondary metabolites and ecologically important chemical compounds in plants and am using my dissertation to investigate the genetics of linalool production in Oenothera harringtonii. This species of evening primrose is polymorphic for linalool production, which is a floral volatile potentially involved in both pollinator and herbivore interactions. My work uses parentage analysis in natural populations, greenhouse studies, and genome-wide association studies to understand the gene(s) and alleles underlying this polymorphism and their movement through populations.
Plant Biology and Conservation Program - NU/CBG
Co-Advised with Norm Wickett
After graduating with a BS in Biology from Brown University in 2017 and working as a research assistant for the Conservation and Land Management Program and the Landscapes of Linalool project in the Skogen Lab, I started graduate school as a Masters student with Dr Skogen in 2019. I have since transitioned to the PhD program and am primarily advised by Dr Wickett but continue to work closely with the Skogen Lab as my graduate research builds off their previous work. I am broadly interested in the evolution of secondary metabolites and ecologically important chemical compounds in plants and am using my dissertation to investigate the genetics of linalool production in Oenothera harringtonii. This species of evening primrose is polymorphic for linalool production, which is a floral volatile potentially involved in both pollinator and herbivore interactions. My work uses parentage analysis in natural populations, greenhouse studies, and genome-wide association studies to understand the gene(s) and alleles underlying this polymorphism and their movement through populations.

Alissa Doucet, M.S. Expected 2023
Plant Biology and Conservation Program – NU/CBG
After years spent dreaming of studying plants and animals, I changed careers from counseling to research in 2018. After working in a hospital research institute for a year, I returned to school to study ecology and evolutionary biology. During this time, I volunteered in an urban ecology lab and sought out coursework and research opportunities in ecology. After an eye-opening experience observing plant-insect interactions, I participated in an internship monitoring monarch larvae across experimental milkweed plantings. These experiences in addition to classes in genetics and entomology led to my current interests in studying the genetic consequences of moth pollination, particularly in areas of high land use change. I am broadly interested in mutualistic relationships between plants and insects, as well as population genetics. As a graduate student, I plan to investigate the genetic diversity of Amsonia tharpii, a rare flowering plant thought to be pollinated by hawkmoths. As A. tharpii is heavily impacted by land use change, I am interested in what pollinator group is most important for retaining genetic diversity as well as identifying whether the local community provides the resources needed to support those pollinators across all life stages.
Plant Biology and Conservation Program – NU/CBG
After years spent dreaming of studying plants and animals, I changed careers from counseling to research in 2018. After working in a hospital research institute for a year, I returned to school to study ecology and evolutionary biology. During this time, I volunteered in an urban ecology lab and sought out coursework and research opportunities in ecology. After an eye-opening experience observing plant-insect interactions, I participated in an internship monitoring monarch larvae across experimental milkweed plantings. These experiences in addition to classes in genetics and entomology led to my current interests in studying the genetic consequences of moth pollination, particularly in areas of high land use change. I am broadly interested in mutualistic relationships between plants and insects, as well as population genetics. As a graduate student, I plan to investigate the genetic diversity of Amsonia tharpii, a rare flowering plant thought to be pollinated by hawkmoths. As A. tharpii is heavily impacted by land use change, I am interested in what pollinator group is most important for retaining genetic diversity as well as identifying whether the local community provides the resources needed to support those pollinators across all life stages.

Andrew Davies, Ph.D. Expected 2026
Plant Biology and Conservation Program – NU/CBG
An undergraduate degree in Environmental Sciences from Oregon State University prompted my long-awaited career change from finance to field botany. I graduated in 2018 and began working for the USGS in the Indiana Dunes shortly after. This position gave me a first insight into threatened species work with Cirsium pitcheri(Pitcher’s Thistle) which I was fascinated by. Since, I have worked in Alaska and California as a botany and forestry technician. Through this work I have developed interests in rare plant conservation, and how threatened and endangered species can persist in response to anthropogenic disturbances. More specifically, how population genetics can be used as a tool to better understand small populations in decline. I am also interested in vegetation mapping, habitat suitability modelling, and ecological restoration, particularly for rare species.
Plant Biology and Conservation Program – NU/CBG
An undergraduate degree in Environmental Sciences from Oregon State University prompted my long-awaited career change from finance to field botany. I graduated in 2018 and began working for the USGS in the Indiana Dunes shortly after. This position gave me a first insight into threatened species work with Cirsium pitcheri(Pitcher’s Thistle) which I was fascinated by. Since, I have worked in Alaska and California as a botany and forestry technician. Through this work I have developed interests in rare plant conservation, and how threatened and endangered species can persist in response to anthropogenic disturbances. More specifically, how population genetics can be used as a tool to better understand small populations in decline. I am also interested in vegetation mapping, habitat suitability modelling, and ecological restoration, particularly for rare species.
LAB ALUMNI
Postdocs
Tania Jogesh, Ph.D. Tania was a postdoc on the NSF-Dimensions of Biodiversity project from 2014-2018. Current: Data Scientist with SF Data - City of San Francisco.
Rick Overson, Ph.D. Rick was a postdoc on the NSF-Dimensions of Biodiversity project from 2014-2017. Current: Research Manager, Cease Lab. Julie Ann Wrigley Global Institute of Sustainability. Arizona State University.
Visiting Scientists
Emily Dangremond, Ph.D., 2014-2016. Current: Assistant Professor of Biology, Roosevelt University
Research Assistants
Haley Carter 2017 - 2018 Current: PhD Student, Plant Biology & Conservation - NU/CBG, in Norm Wickett's lab
Lindsey Bechen 2016 - 2018 Current: Research Assistant at the Whitehead Institute, MIT, Cambridge, MA
Andrea Gruver 2015 - 2017 Current: Ms Student, Plant Biology & Conservation - NU/CBG, in Paul Caradonna's lab
Emily Lewis 2014 - 2015 Current: Graduate Coordinator, Department of Math, Washington State University
Evan Hilpman 2008 - 2015 Current: PhD Student, Washington State University in Jeremiah Busch's Lab
Matt Rhodes 2013 - 2015 Current: Ecological Consultant, Lander, WY
Wes Glisson 2013 - 2014 Current: Research Scientist, University of Minnesota, in Dan Larkin's lab
Sadie Todd 2009 - 2013 Current: Entomologist, Iowa Department of Agriculture and Land Stewardship
Graduate Students (2 Ph.D., 9 M.S.)
Katie Wenzell, Ph.D. 2021. Plant Biology and Conservation Program - NU/CBG. Do Pollinators Drive Divergence? Connecting Floral Phenotypes, Pollinators, and Gene Flow to Understand Floral Trait Divergence in Castilleja. Current: Postdoctoral scientist, John Innes Center, Norwich, UK. Kelsey Byer's lab.
Katherine (Kat) Andrews, M.S. 2019. Plant Biology and Conservation Program - NU/CBG. Precipitation frequency negatively impacts plant survivorship, growth, phenology and herbivory in Oenothera harringtonii. Current: Director of cultivation, Standards and Practicies, Cresco Labs.
Kelly Ksiazek-Mikenas, Ph.D. 2017. Plant Biology and Conservation - Chicago Botanic Garden & Northwestern University. The potential of green roofs to provide habitat for native plant conservation. Current Position: Assistant Professor, Department of Biology; Director, Environmental Studies Program Biology Department, Elmhurst College.
Dan Bruzzese, M.S. 2016. Plant Biology and Conservation - Chicago Botanic Garden & Northwestern University. Host use and diversification of the genus Mompha (Lepidoptera: Gelechioidea: Momphidae). Current: Ph.D. student in Jeff Feder’s lab at the University of Notre Dame.
Ben Cooper, M.S. 2016. Plant Biology and Conservation - Chicago Botanic Garden & Northwestern University. Revealing patterns of evolution in a recently radiated plant group, the Sundrops (Oenothera Section Calylophus: Onagraceae) using target enrichment. Current: Data analyst, National Park Service, Las Cruces, NM.
Emily Lewis, M.S. 2015. Plant Biology and Conservation - Chicago Botanic Garden & Northwestern University. Differences in population genetic structure of hawkmoth- and bee-pollinated species of Oenothera (Onagraceae) are more pronounced at a landscape scale. Current: Graduate Coordinator, Department of Math, Washington State University
Matt Rhodes, M.S. 2013. Plant Biology and Conservation - Chicago Botanic Garden & Northwestern University. Spatial genetic structure and nonrandom pollination success in Oenothera harringtonii (Onagraceae). Current: Ecological Consultant, Lander, WY
Ricky Rivera M.S., 2013. Plant Biology and Conservation - Chicago Botanic Garden & Northwestern University. Quantitative genetics in a fragmented landscape, a study of heritable floral traits in Oenothera harringtonii (Onagraceae). Current: Ph.D. student at the University of Wisconsin - Madison in Erika Marin-Spiotta's lab
Rebecca Barak, M.S., 2012. Plant Biology and Conservation - Chicago Botanic Garden & Northwestern University. Assessing restoration potential of native forbs from cheatgrass-dominated habitats. Current: Assistant Conservation Scientist, Chicago Botanic Garden.
Emily Booth, M.S., 201. Plant Biology and Conservation - Chicago Botanic Garden & Northwestern University. Potential effects of climate change on Penstemon palmeri at Zion National Park, Utah, U.S. Current: Postdoctoral researcher, Brent Sewall’s lab at Temple University.
Melissa Gray, M.S. 2011. Plant Biology and Conservation - Chicago Botanic Garden & Northwestern University. The effects of floral density manipulation on the pollination and reproductive success of Penstemon pachyphyllus. Current: Assistant editor in Plant and Environmental Science at Encyclopedia Britannica - Greater Chicago Area
Undergraduate Students
Kyann Young. Saint Xavier University. Research Intern. Summer 2021.
Laura Fehling. University of Wisconsin – Green Bay. REU Student Summer 2018.
Casey Beidelman Northwestern University. Research intern. Summer 2017.
Sydney Weil. Amherst College, 2018. Research Intern Summer 2017.
Melissa Vergara. University of California - Santa Cruz, 2018. REU Student Spring 2017.
Victoria Luizzi. Amherst College, 2017. REU Student Summer 2016.
Amanda Patsis. Amherst College, 2017. Research Intern Summers 2015, 2016.
Lindsey Bechen. Amherst College, 2016. Research Intern Summer 2015.
Adam Rork. Maryville University, 2017. REU Student Summer 2015.
Evan Levy. Colorado College, 2015. REU Student Summer 2015.
Taylor Tate. Northwestern University, 2015. Research intern 2013-2015.
Katherine (Kat) Andrews. Lake Forest College, 2015. Research intern 2013-2015.
Andrea Gruver. Gustavus Adolphus College, 2015. REU Student Summer 2014.
James Medina. Oberlin College, 2015. Summer 2012, Jan 2013, Summer 2013.
Evan Hilpman. Colorado College, 2010. Senior thesis co-advisor. Genetic analysis of a Colorado endemic threatened by anthropogenic landscape alteration: Oenothera harringtonii (Onagraceae).
Sadie Todd. University of Missouri, Columbia, 2010. Summer 2009
Kathleen (KC) West. Claremont McKenna College, 2012. Winter 2012
Heather-Rose Kates. Oberlin College, 2011. NSF REU Student: 2010. Variation in floral morphology in Oenothera harringtonii.
Carrie Klase. Warren Wilson College, 2012. NSF REU Student: 2009. Oenothera harringtonii fruit and seed morphology, weight, & seed viability analyses.
Quincy Roberts. Lake Forest College, 2009. Research Intern: 2008 – 2009.
Logan Senack. University of Connecticut, University Scholar and Honors Student, 2008. Senior thesis co-advisor: 2006 –2008. Seed size, germination, and the effects of herbivory in rare and common Desmodium species.
Postdocs
Tania Jogesh, Ph.D. Tania was a postdoc on the NSF-Dimensions of Biodiversity project from 2014-2018. Current: Data Scientist with SF Data - City of San Francisco.
Rick Overson, Ph.D. Rick was a postdoc on the NSF-Dimensions of Biodiversity project from 2014-2017. Current: Research Manager, Cease Lab. Julie Ann Wrigley Global Institute of Sustainability. Arizona State University.
Visiting Scientists
Emily Dangremond, Ph.D., 2014-2016. Current: Assistant Professor of Biology, Roosevelt University
Research Assistants
Haley Carter 2017 - 2018 Current: PhD Student, Plant Biology & Conservation - NU/CBG, in Norm Wickett's lab
Lindsey Bechen 2016 - 2018 Current: Research Assistant at the Whitehead Institute, MIT, Cambridge, MA
Andrea Gruver 2015 - 2017 Current: Ms Student, Plant Biology & Conservation - NU/CBG, in Paul Caradonna's lab
Emily Lewis 2014 - 2015 Current: Graduate Coordinator, Department of Math, Washington State University
Evan Hilpman 2008 - 2015 Current: PhD Student, Washington State University in Jeremiah Busch's Lab
Matt Rhodes 2013 - 2015 Current: Ecological Consultant, Lander, WY
Wes Glisson 2013 - 2014 Current: Research Scientist, University of Minnesota, in Dan Larkin's lab
Sadie Todd 2009 - 2013 Current: Entomologist, Iowa Department of Agriculture and Land Stewardship
Graduate Students (2 Ph.D., 9 M.S.)
Katie Wenzell, Ph.D. 2021. Plant Biology and Conservation Program - NU/CBG. Do Pollinators Drive Divergence? Connecting Floral Phenotypes, Pollinators, and Gene Flow to Understand Floral Trait Divergence in Castilleja. Current: Postdoctoral scientist, John Innes Center, Norwich, UK. Kelsey Byer's lab.
Katherine (Kat) Andrews, M.S. 2019. Plant Biology and Conservation Program - NU/CBG. Precipitation frequency negatively impacts plant survivorship, growth, phenology and herbivory in Oenothera harringtonii. Current: Director of cultivation, Standards and Practicies, Cresco Labs.
Kelly Ksiazek-Mikenas, Ph.D. 2017. Plant Biology and Conservation - Chicago Botanic Garden & Northwestern University. The potential of green roofs to provide habitat for native plant conservation. Current Position: Assistant Professor, Department of Biology; Director, Environmental Studies Program Biology Department, Elmhurst College.
Dan Bruzzese, M.S. 2016. Plant Biology and Conservation - Chicago Botanic Garden & Northwestern University. Host use and diversification of the genus Mompha (Lepidoptera: Gelechioidea: Momphidae). Current: Ph.D. student in Jeff Feder’s lab at the University of Notre Dame.
Ben Cooper, M.S. 2016. Plant Biology and Conservation - Chicago Botanic Garden & Northwestern University. Revealing patterns of evolution in a recently radiated plant group, the Sundrops (Oenothera Section Calylophus: Onagraceae) using target enrichment. Current: Data analyst, National Park Service, Las Cruces, NM.
Emily Lewis, M.S. 2015. Plant Biology and Conservation - Chicago Botanic Garden & Northwestern University. Differences in population genetic structure of hawkmoth- and bee-pollinated species of Oenothera (Onagraceae) are more pronounced at a landscape scale. Current: Graduate Coordinator, Department of Math, Washington State University
Matt Rhodes, M.S. 2013. Plant Biology and Conservation - Chicago Botanic Garden & Northwestern University. Spatial genetic structure and nonrandom pollination success in Oenothera harringtonii (Onagraceae). Current: Ecological Consultant, Lander, WY
Ricky Rivera M.S., 2013. Plant Biology and Conservation - Chicago Botanic Garden & Northwestern University. Quantitative genetics in a fragmented landscape, a study of heritable floral traits in Oenothera harringtonii (Onagraceae). Current: Ph.D. student at the University of Wisconsin - Madison in Erika Marin-Spiotta's lab
Rebecca Barak, M.S., 2012. Plant Biology and Conservation - Chicago Botanic Garden & Northwestern University. Assessing restoration potential of native forbs from cheatgrass-dominated habitats. Current: Assistant Conservation Scientist, Chicago Botanic Garden.
Emily Booth, M.S., 201. Plant Biology and Conservation - Chicago Botanic Garden & Northwestern University. Potential effects of climate change on Penstemon palmeri at Zion National Park, Utah, U.S. Current: Postdoctoral researcher, Brent Sewall’s lab at Temple University.
Melissa Gray, M.S. 2011. Plant Biology and Conservation - Chicago Botanic Garden & Northwestern University. The effects of floral density manipulation on the pollination and reproductive success of Penstemon pachyphyllus. Current: Assistant editor in Plant and Environmental Science at Encyclopedia Britannica - Greater Chicago Area
Undergraduate Students
Kyann Young. Saint Xavier University. Research Intern. Summer 2021.
Laura Fehling. University of Wisconsin – Green Bay. REU Student Summer 2018.
Casey Beidelman Northwestern University. Research intern. Summer 2017.
Sydney Weil. Amherst College, 2018. Research Intern Summer 2017.
Melissa Vergara. University of California - Santa Cruz, 2018. REU Student Spring 2017.
Victoria Luizzi. Amherst College, 2017. REU Student Summer 2016.
Amanda Patsis. Amherst College, 2017. Research Intern Summers 2015, 2016.
Lindsey Bechen. Amherst College, 2016. Research Intern Summer 2015.
Adam Rork. Maryville University, 2017. REU Student Summer 2015.
Evan Levy. Colorado College, 2015. REU Student Summer 2015.
Taylor Tate. Northwestern University, 2015. Research intern 2013-2015.
Katherine (Kat) Andrews. Lake Forest College, 2015. Research intern 2013-2015.
Andrea Gruver. Gustavus Adolphus College, 2015. REU Student Summer 2014.
James Medina. Oberlin College, 2015. Summer 2012, Jan 2013, Summer 2013.
Evan Hilpman. Colorado College, 2010. Senior thesis co-advisor. Genetic analysis of a Colorado endemic threatened by anthropogenic landscape alteration: Oenothera harringtonii (Onagraceae).
Sadie Todd. University of Missouri, Columbia, 2010. Summer 2009
Kathleen (KC) West. Claremont McKenna College, 2012. Winter 2012
Heather-Rose Kates. Oberlin College, 2011. NSF REU Student: 2010. Variation in floral morphology in Oenothera harringtonii.
Carrie Klase. Warren Wilson College, 2012. NSF REU Student: 2009. Oenothera harringtonii fruit and seed morphology, weight, & seed viability analyses.
Quincy Roberts. Lake Forest College, 2009. Research Intern: 2008 – 2009.
Logan Senack. University of Connecticut, University Scholar and Honors Student, 2008. Senior thesis co-advisor: 2006 –2008. Seed size, germination, and the effects of herbivory in rare and common Desmodium species.