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Contact Information

P: 864-656-2328

Campus Location

132 Long Hall, Clemson, SC 29634


Monday - Friday:
8 a.m. - 4:30 p.m.


Profile Photo

Krissa Skogen

Biological Sciences

Associate Professor

AG Biotech/Biosystems Research Complex / BRC GH124 [Greenhouse Service]
Jordan Hall 118A [Lab]
Jordan Hall 118C [Lab]
Long Hall 350 [Office]

Educational Background

Ph.D., Ecology, University of Connecticut, 2008
B.A., Biology, Gustavus Adolphus College, 2000

Research Interests

Plant reproductive biology; Plant-Animal Interactions; Pollination; Evolutionary Ecology; Population Genetics

Understanding the diversity of life starts with uncovering the evolutionary histories and relationships between interacting organisms and landscapes. As a botanist, I am fascinated by the rich diversity of flowering plants (angiosperms) and the insects that interact with them - both pollinators and antagonists (herbivores, seed predators, etc.) - and how these interactions may help explain the great diversity we see today. Much of my work focuses on differences between hawkmoth- and bee-pollinated plant species and the implications for floral phenotypes (shape, color, size, scent), population connectivity, and species boundaries. I'm also fascinated by the role that antagonists may play, especially those that are attracted to the same floral cues that attract pollinators (including color and scent) given the opposing, negative impacts of floral antagonists on plant fitness. Much of this work uses the Geographic Mosaic Theory of Coevolution as a model to explain the evolutionary relationships between members of the evening primrose family, Onagraceae, their hawkmoth and bee pollinators, and antagonist microlepidoptera in the genus Mompha (more info here).

I am also committed to plant conservation efforts, including investigating the impacts of anthropogenic factors on plants and pollinators. New funding from the Fish and Wildlife Foundation and the Bureau of Land Management will explore the impact of oil and gas development on the rare Amsonia tharpii (Apocynaceae) which will inform decisions on its listing on the Endangered Species Act as well as management and conservation decisions to conserve extant populations.

My previous work has investigated the impact of land use change on an endemic, hawkmoth-pollinated evening primrose, Oenothera harringtonii and the role that atmospheric nitrogen deposition may have played in the decline of the nitrogen-fixing legume, Desmodium cuspidatum.

Courses Taught

Biology of Plants - Biol 3040, 3080

Selected Publications

Since 2017
*student authors, +postdocs

Lewis, E. M, J. B. Fant, M, J. Moore, and K. A. Skogen. In Review. Hawkmoth and bee pollinators impact pollen dispersal at the landscape but not local scales in two species of Oenothera (Onagraceae). American Jornal of Botany.

Ksiazek-Mikenas*, K., V. B. Chaudhary, and K. A. Skogen. In Review. Native plant communities provide enhanced stomwater capture and evapotranspiration compared to Sedum on green roofs. Urban Ecosystems.

Wenzell*, K. E., K. A. Skogen, and J. B. Fant. In Revision. Range-wide floral trait variation reflects shifts in pollinator assemblages, consistent with pollinator-mediated divergence despite generalized visitation. Oikos.

Li*, B., J. Fant, J. Zeldin, K. Skogen, and K. Havens. In Revision. Genetic and floral trait changes in Oenothera organensis (Onagraceae) during long-term ex situ cultivation. International Journal of Plant Sciences.

Diaz-Martin, Z.+, A. Cisternas-Fuentes*, K. M. Kay, R. A. Raguso, K. A. Skogen, and J. B. Fant. In Revision. Shifts in reproductive strategies and their consequences for divergence, gene flow, and genetic diversity. Heredity.

Overson+, R. P., M. G. Johnson, L. L. Bechen*, S. P. Kinosian+, N. A. Douglas, J. B. Fant, P. C. Hoch, R. A. Levin, M.J. Moore, R. A. Raguso, W. L. Wagner, K. A. Skogen, N. J. Wickett. In press. A phylogeny of the evening primrose family (Onagraceae) using a target enrichment approach with 303 nuclear loci. BMC Ecology and Evolution.

Cooper*, B. J., M. J. Moore, N. A. Douglas, W. L. Wagner, M. G. Johnson, R. P. Overson+, S. P. Kinosian+, A. J. McDonnell+, R. A. Levin, R. A. Raguso, H. F. Olvera. H. Ochoterena, J. B. Fant, K. A. Skogen, and N. J. Wickett. 2022. Target enrichment and extensive population sampling help untangle the recent, rapid radiation of Oenothera sect. Calylophus. Systematic Biology.Syac032.

Cisternas Fuentez, A.*, T. Jogesh+, G. T. Broadhead*, R. A. Raguso, K. A. Skogen, and J. B. Fant. 2022. Evolution of the selfing syndrome and its influence on genetic diversity and inbreeding: A range-wide study in Oenothera primiveris (Onagraceae). American Journal of Botany. 109(5):1-17.

Balbuena+, M., G. Broadhead*, A. Dahake*, E. Barnett*, M. Verrera*, K. Skogen, T. Jogesh+, and R. Raguso. 2022. Mutualism has its limits: consequences of asymmetric interactions between a well-defended plant and its herbivorous pollinator. 2022. Invited submission for special issue “From chemistry to landscapes: natural processes influencing pollinator health”. Philosophical Transactions of the Royal Society B. 377: 20210166.

Skogen, K., T. Jogesh+, E, Hilpman*, Sadie Todd*, and R. Raguso. 2022. ?Extensive population-level sampling reveals clinal variation in (R)(-)-linalool produced by the flowers of an endemic evening primrose, Oenothera harringtonii. Phytochemistry. Phytochemistry. 200: 113185

Bechen*, L., M. Johnson, G. Broadhead*, R. Levin, R. Overson+, T. Jogesh+, J. Fant, R. Raguso, K. Skogen, N. Wickett. 2022. Differential gene expression associated with a floral scent polymorphism in the evening primrose Oenothera harringtonii (Onagraceae). BMC Genomics.

Patsis*, A., R. Overson+, K. Skogen, N. Wickett, M. Johnson, W. Wagner, R. Raguso, J. Fant, and R. Levin. 2021. Elucidating the evolutionary history of Oenothera Sect. Pachylophus (Onagraceae): A phylogenetic approach. Systematic Botany. 46(3):799-811.

Ksiazek-Mikenas*, K., Chaudhary, B. Larkin, D., and K. Skogen. 2021. A habitat analog approach establishes native plant communities on green roofs. Ecosphere. 12(9): e03754

Wenzell*, K., A. McDonnell+, J. Fant and K. Skogen. 2021. Floral color variation reveals contrasting patterns of genomic and phenotypic divergence within and among species of Castilleja. American Journal of Botany. Open Access.

Skogen, K., R. Overson+, E. Hilpman*, and J. Fant. 2019. Hawkmoth pollination facilitates long distance pollen dispersal and reduces isolation across a gradient of land-use change. Annals of the Missouri Botanical Garden. 104(3): 495-511. DOI: Open Access.

Mikenas*, K., J. Fant, and K. Skogen. 2019. Pollinator-mediated gene flow connects green roof populations across the urban matrix: a paternity analysis of the self-compatible forb Penstemon hirsutus. Frontiers in Ecology and Evolution. 7:299. DOI: 10.3389/fevo.2019.00299 Open Access.

Bruzzese*, D. J., D. L. Wagner, T. Harrison, T. Jogesh+, R. P. Overson+, N. J. Wickett, R. A. Raguso, and K. A. Skogen. 2019. Diversification in the microlepidopteran genus Mompha (Lepidoptera: Gelechioidea: Momphidae) is explained more by tissue specificity than host plant family. PLoS ONE. 14(6) e0207833. Open Access.

Jogesh, T.+, G. T. Broadhead*, R. A. Raguso, and K. A. Skogen. 2018. Intraspecific floral diversity in the California evening primrose, Oenothera californica subsp. avita. Mojave National Preserve Science Newsletter. 12-16.

Rhodes, M. K.*, J. B. Fant, and K. A. Skogen. 2017. Pollinator identity and spatial isolation influence multiple paternity in an annual plant. Molecular Ecology. 26(16): 4296–4308. doi: 10.1111/mec.14115


Botanical Society of America
American Society of Plant Taxonomists
Plant Conservation Alliance - Non-Federal Cooperators Committee

Contact Information

P: 864-656-2328

Campus Location

132 Long Hall, Clemson, SC 29634


Monday - Friday:
8 a.m. - 4:30 p.m.