Evolutionary strategies and phenotypic plasticity in the stellaria longipes complex (caryophyllaceae)

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I have been interested in the origin and evolution of polyploids. My research has largely focused on the Stellaria longipes complex (Caryophyllaceae). S. longipes is a polyploid and essentially a North American taxon. It is widely distributed on the continent, but also extends into parts of Eurasia, there by attaining a circumpolar distribution. It grows in a variety of habitats, is extremely plastic and a highly successful colonizer. I am attempting to understand the evolutionary strategies of this species. Our work since 1979 points out two important aspects of the biology of the species which contributed towards its success. A) Genetic variability due to polyploidy, facultative outbreeding and interspecific gene flow. B) Development of phenotypic plasticity due to environmentally induced changes in the physiology and morphological expression of the genotypes. My laboratory is currently involved in the continued studies of 1) origin and diversification of the species, and 2) understanding the genetic mechanisms and the adaptive significance of phenotypic plasticity in this species. The idea that biologists need to work downward from phenotypic variation to the physiological effects of genetic and environmental variation is now well recognized. My research program is essentially a 'collaborative' interaction between population biology, ecophysiology, molecular biology and biosystematics. Blending among these disciplines has been a promising endeavor to my understanding of the evolution of this widely distributed extremely plastic and highly successful herbaceous perennial plant species.