Abstract
Gene flow can have an especially strong impact on the evolution of small populations. However, empirical studies on the actual rates and patterns of gene flow into small populations are few. Thus, we sought to measure gene flow into small populations of wild radish. Raphanus sativus. We found significant differences in gene flow receipt among experimental populations and within those populations over a season. A maximum-likelihood estimate revealed that almost all of the gene flow into these synthetic populations had its origin in relatively distant (>650 m), large natural populations rather than the proximal (255-400 m), small synthetic populations. We also estimated rates of interpopulation mating from simple paternity analysis of progeny produced by seven small (ca. 50 plants) natural populations. Again, we found significant heterogeneity in gene flow receipt. Although these populations varied 10-fold in their range of isolation distances (100-1000 m), gene flow rates did not vary with distance. The magnitude of gene flow rates estimated in all but one population was great enough for gene flow to play an important role in the evolution of these small populations.
Keywords: Raphanus sativus, spatial isolation, interpopulation mating
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Selected References
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- Ehrlich P. R., Raven P. H. Differentiation of populations. Science. 1969 Sep 19;165(3899):1228–1232. doi: 10.1126/science.165.3899.1228. [DOI] [PubMed] [Google Scholar]
- Frost H B. Heterosis and Dominance of Size Factors in Raphanus. Genetics. 1923 Mar;8(2):116–153. doi: 10.1093/genetics/8.2.116. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schoen D. J., Stewart S. C. Variation in Male Fertilities and Pairwise Mating Probabilities in Picea glauca. Genetics. 1987 May;116(1):141–152. doi: 10.1093/genetics/116.1.141. [DOI] [PMC free article] [PubMed] [Google Scholar]