Robert S. Wallace

Ph.D., Rutgers University, 1988.


Department of Ecology, Evolution and Organismal Biology
Iowa State University
353 Bessey Hall
Ames, IA  50011-1020


311 Bessey Hall
(515) 294-0367
(515) 294-1337


Research Interests

My research interests involve the study of evolutionary relationships in diverse plant groups with the goals of constructing phylogenies for them, and the application of the new information toward a taxonomic re-evaluation of the group. In particular, I am interested in the utilization of data derived from biochemical/molecular investigations (nucleic acids, proteins, secondary compounds) in concert with morphological, cytological, and biogeographic data to examine plant evolution in a multidisciplinary fashion. Currently my research efforts focus on developing a better understanding of the phylogeny of the cactus family at a number of taxonomic levels, using chloroplast DNA variation to assess degrees of evolutionary relatedness within and between major evolutionary lineages. On a larger scale, I am also examining interfamilial relationships within the Caryophyllales (Centrospermae), a rather well-defined order of angiosperms. Studies involving restriction fragment analysis (RFLP), comparative genome structure (chloroplast DNA), and comparative gene sequencing are in progress. Other interests are in succulent plant evolution, systematics and evolution of Aizoaceae, and bryophyte systematics.

Additional Links:

Recent News:


Beer and Brewing

"Beer Man" - College Newsletter 2004

Wood and Woodworking


Selected Publications

  • Wallace, R.S. and R.K. Jansen. 1990. Systematic implications of chloroplast DNA variation in the genus Microseris (Asteraceae: Lactuceae). Systematic Botany 15:606-616.

  • Jansen, R.K., R.S. Wallace, K.-J. Kim, and K.L. Chambers. 1991. Systematic implications of chloroplast DNA variation in the subtribe Microseridinae (Asteraceae: Lactuceae). American Journal of Botany 78:1015-1027.

  • Kim, K.-J., R.K. Jansen, R.S. Wallace, H.J. Michaels, and J.D. Palmer. 1992. Phylogenetic implications of rbcL sequence variation in the Asteraceae. Annals of the Missouri Botanical Garden 79:428-445.

  • Jansen, R.K., H.J. Michaels, R.S. Wallace, K.-J. Kim, S.C. Keeley, L.E. Watson, and J.D. Palmer. 1992. "Chloroplast DNA variation in the Asteraceae: Phylogenetic and evolutionary implications". (In) Molecular Systematics of Plants (P.S. Soltis, D.E. Soltis and J.J. Doyle, eds.) Chapman and Hall, New York.

  • Wallace, R.S. 1994. Phylogenetic Analysis of Eriosyce (In.) Eriosyce (Cactaceae) the genus revised and amplified by F. Kattermann. Succulent Plant Research 1:125-130.

  • Cota, J.H., R.S. Wallace, and L.G. Clark. 1995. Notes on the cacti of Quintana Roo, Mexico. Cactus and Succulent J. (U.S.) 67:294-300.

  • Whitton, J., R.S. Wallace, R.K. Jansen. 1995. Phylogenetic relationships and patterns of character change in the tribe Lactuceae (Asteraceae) based on chloroplast DNA restriction site variation. Canadian Journal of Botany 73:1058-1073.

  • Wallace R.S. and J.H. Cota. 1995. An intron loss in the chloroplast gene rpoC1 support: a monophyletic origin for the subfamily Cactoideae of the Cactaceae. Curr. Genet. 29:275-281.

  • Wallace R.S. and R.K. Jansen. 1995. DNA evidence for multiple origins of intergeneric allopolyploids in annual Micorseris (Asteraceae). Plant Systematics and Evolution 198:253-265.

  • Wallace, R.S. 1995. Molecular systematic study of the Cactaceae: Using chloroplast DNA variation to elucidate cactus phylogeny. Bradleya 13:1-12.

  • Anderson, E.F. and R.S. Wallace. 1999. Botanists in Paradise. Part 2: Adventures in Peru. Cactus and Succulent Journal 71:236-244.

  • Butterworth, C. and R.S. Wallace. 1999. Phylogenetic studies of the tribe Cacteae. Cactaceae Consensus Initiatives 8:7-9.

  • Applequist, W.L. and R.S. Wallace. 2000. Phylogeny of the Madagascan endemic family Didiereaceae. Plant Systematics and Evolution 221:157-166.

  • Martin, C. E. and R.S. Wallace 2000. Photosynthetic pathway variation in leafy members of two subfamilies of Cactaceae. International J. Plant. Science 161: 639-650.

  • Applequist, W.L. and R.S. Wallace. (submitted) Phylogeny of the portulacaceous cohort based on ndhF sequence data. Systematic Botany.

  • Dickie, S.L. (in review). Phylogeny and evolution in Subfamily Opuntioideae (Cactaceae): Insights from rpl16 intron sequence variation. Systematic Botany.

  • Wallace, R.S. (in press) An overview of columnar cactus evolution and systematics. (In) T.H. Fleming and A. Valiente Banuet (Eds.) Evolution, Ecology, and Conservation of Columnar Cacti and their Mutualists. University of Arizona Press, Tucson.

  • Wallace, R.S. and A.C. Gibson. (in review) Phylogeny and Systematics of the Cactaceae. (In) P.S. Nobel (Ed.) Biology of the Cactaceae (tentative title). University of California Press.

updated 03/22/2004