Variation and Selection in Plant Populations

Abstract

It seems customary to include a chapter on plants in many population biology and evolutionary volumes with the purpose of emphasizing certain characteristics of plants and somewhat balancing the animal examples prevalent in the remaining chapters. The latter is not the case here since many chapters refer to plants, but as G.L. Stebbins (1950) wrote his masterpiece, Variation and Evolution in Plants, he continually tested most of the known population genetic and biosystematic ideas comparatively for plants versus animals. His chapters covered environmentally induced variation; ecotype, clinal and subspecies variation; evidence for natural selection; genetic systems involving hybridization, polyploidy, autogamy, and apomixis; and karyotype or genome evolution versus external morphology. Clearly, plant researchers have continued to emphasize these topics; more recently, demography and physiological ecology have been discussed in several volumes devoted to plant research. Stebbins (1950) established the role of genetic ideas in all of this with a wealth of succinct hypotheses and examples, combining the deductive and inductive approaches. A recent book with a very similar title (Briggs and Walters 1984. Plant Variation and Evolution) reaffirms many of these ideas even without covering with enthusiasm or rigor many new developments or emerging biosystematic topics in population biology.