Skip to main content Skip to navigation

Eric H. Roalson

Eric Roalson

Eric H. Roalson

Field of Study: Plant Systematics
Title: Professor
Degrees: Ph.D., Botany, Rancho Santa Ana Botanic Garden and The Claremont Graduate University
Homepage: Homepage/Lab Web Site Link
Google Scholar:  Google Scholar
Office: 435 Owen Science Library
Phone: 509-335-7921
Fax: nan
Mailing Address: School of Biological Sciences
Washington State University
PO Box 644236
Pullman,WA 99164-4236


Systematists and molecular phylogeneticists study the patterns and processes of organismal diversity, from the gene to the organism to the clade level, and ask questions focused on how the diversity we see has originated, and how different processes have led to these diversification patterns. Integration of studies across these different hierarchical levels is important to understand not only how lineages have diversified, and how they might be classified, but also what processes might have been important. My research has focused on two general questions: (1) what are the patterns of angiosperm diversity, from species boundaries to clade classifications to historical biogeography; and (2) what are the evolutionary dynamics of morphological and physiological traits (and their underlying genes) important to diversification, particularly floral structural changes and photosynthetic pathway modification. Current projects focus on the Cyperaceae, Gesneriaceae, Cleomaceae, and Chenopodiaceae, with studies exploring a variety of phylogenetic, cytogenetic, morphological, and physiological questions.

Representative Publications:

  • Roalson EH, Jiménez-Mejías P, Hipp AL, Benítez-Benítez C, Bruederle LP, Chung K-S, Escudero M, Ford BA, Ford KA, Gebauer S, Gehrke B, Hahn M, Hayat MQ, Hoffmann MH, Jin X-F, Kim S, Larridon I, Léveillé-Bourret É, Lu Y-F, Luceño M, Maguilla E, Márquez-Corro JI, Martín-Bravo S, Masaki T, Míguez M, Naczi RFC, Reznicek AA, Spalink D, Starr JR, Uzma, Villaverde T, Waterway MJ, Wilson KL, Zhang S-R. 2021. A framework infrageneric classification of Carex (Cyperaceae) and its organizing principles. Journal of Systematics and Evolution 59: 726–762.
  • Larridon I, Zuntini AR, Barrett RL, Wilson KL, Bruhl JJ, Goetghebeur P, Baker WJ, Brewer GE, Epitawalage N, Fairlie I, Forest F, Kikuchi I, Pokorny L, Semmouri I, Spalink D, Simpson DA, Muasya AM, Roalson EH. 2021. Resolving the generic limits in Cyperaceae tribe Abildgaardieae using targeted sequencing. Botanical Journal of the Linnean Society 196: 163–187.
  • Soares Neto RL, Roalson EH. 2020. Taxonomic revision of two Neotropical Cleomaceae genera, Dactylaena and Haptocarpum. Systematic Botany 45: 544–553.
  • Villaverde T, Jiménez-Mejías P, Luceño M, Waterway MJ, Kim S, Lee B, Rincón-Barrado M, Hahn M, Maguilla E, Roalson EH, Hipp AL (and the Global Carex Group). 2020. A new classification of Carex subgenera supported by a HybSeq backbone phylogeny. Botanical Journal of the Linnean Society 194: 141–163.
  • Soares Neto RL, Thomas WW, Barbosa MR, Roalson EH. 2020. Diversification of New World Cleomaceae with emphasis on Tarenaya and the description of Iltisiella, a new genus. Taxon 69: 321–336.
  • Roberts WR, Roalson EH. 2020. Co-expression clustering across flower development identifies modules for diverse flowers in Achimenes (Gesneriaceae). PeerJ 8: e8778.
  • Martín-Bravo S, Jiménez-Mejías P, Villaverde T, Escudero M, Hahn M, Spalink D, Roalson EH, Hipp AL, and the Global Carex Group (Benítez-Benítez C, Bruederle LP, Fitzek E, Ford BA, Ford KA, Garner M, Gebauer S, Hoffmann MH, Jin X-F, Larridon I, Léveillé-Bourret E, Lu Y-F, Luceño M, Maguilla E, Márquez-Corro JI, Míguez M, Naczi RFC, Reznicek AA, Starr JR). 2019. A tale of worldwide success: behind the scenes of Carex (Cyperaceae) biogeography and diversification. Journal of Systematics and Evolution 57: 695–718.
  • Kleinkopf J, Roberts WR, Wagner WL, Roalson EH. 2019. Diversification of Hawaiian Cyrtandra (Gesneriaceae) and the influence of incomplete lineage sorting and hybridization. Journal of Systematics and Evolution 57: 561–578.
  • Roberts WR, Roalson EH. 2018. Transcriptomic evidence of gene flow between species of magic flowers (Achimenes, Gesneriaceae). American Journal of Botany 105: 726–740.
  • Roberts WR, Roalson EH. 2017. Comparative transcriptome analyses of flower development in four species of Achimenes (Gesneriaceae). BMC Genomics 18: 240.
  • Roalson EH, Roberts WR. 2016. Distinct processes drive diversification in different clades of Gesneriaceae. Systematic Biology 65: 662–684.
  • Hinchliff, C. E. and E. H. Roalson. 2013. Using supermatrices for phylogenetic inquiry: an example using the sedges. Systematic Biology 62: 205–219.