Jan Erik Aagaard
jaagaard@darkwing.uoregon.edu

University of Oregon
Center for Ecology and Evolution
Department of Biology
1210 University of Oregon
Eugene, OR 97403-1210 USA

Advisors:
Dr. Patrick C. Phillips, Program in Ecology & Evolution
Dr. John H. Postlethwait, Institute of Neuroscience

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Research Interests

I am interested in the morphological evolution of reproductive structures of flowering plants. Though angiosperms appear only recently in the history of eukaryotes (approx. 150-170 MYA), they radiated rapidly and now fill every imaginable ecological role. The rapid evolution of angiosperms is thought to be due in large part to the flower itself - floral structures have provided for reproductive isolation, coevolution between pollinators and seed dispersers, and colonization of novel habitats. Surprisingly, the genetic basis underlying development of flowers appears to be conserved among most angiosperms despite the large degree of morphological divergence. How can the highly conserved developmental program regulating floral development accommodate the morphological diversity we see among flowers?

I am addressing two prominent questions in the evolution of development aimed at understanding the genetic basis of morphological evolution. First, what are the genes regulating floral development which are most likely to be acted upon by selection during evolution? Second, how might duplication of genes which regulate floral development contribute to morphological evolution? My research involves cloning three genes which regulate the development of flowers from floral induction through organogenesis (LFY/FLO, UFO/FIM, and AP3/DEF) from a variety of species within the Phrymaceae (formerly Scrophulariaceae; Lamiales). I measure rates of nucleotide substitutions at both amino-acid replacement sites and silent sites, and conduct a variety of statistical tests in order to ask questions such as:

… Do genes acting early in development evolve at different rates than genes acting later in the same pathway? … Is there evidence that selective constraints or adaptive evolution differentially affect these genes? … If members of a particular developmental pathway are duplicated, is there evidence that gene duplicates evolve at different rates? … Are gene duplicates differentially affected by selective constraints or adaptive evolution? … Are there particular functional regions of genes which differ in their rate of evolution between duplicates and which may be the target of selection?

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Publications

• Aagaard, J.E., Vollmer, S.S., Sorensen, F.C., and Strauss, S.H. (1995) Mitochondrial DNA products among RAPD profiles are frequent and strongly differentiated between races of Douglas-fir. Mol. Ecol. 4(4):441-446.