DNA and Morphology: Comparisons in the Onagraceae

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Abstract
Comparisons of systematic information generated from both classical systematic approaches and from DNA analysis at a number of taxonomic levels in the Onagraceae are presented. Phylogenetic results from chloroplast DNA restriction fragment analysis in Clarkia sect. Sympherica (= Peripetasma) are not entirely congruent with results from morphology, but are congruent with distribution of duplications of isozyme-coding loci. Chloroplast DNA and nuclear rDNA evidence for the origin of the monotypic genus Heterogaura from the within the genus Clarkia is discussed with respect to morphological divergence between the two genera. Detailed chloroplast DNA restriction site mapping within the seven diploid sections of Clarkia and subsequent preliminary intersectional phylogenetic analysis are presented. These DNA-based relationships are compared with a morphological and cytological model of relationships, and to various gene duplication-based models. Section Godetia is implicated as the sister group to the rest of Clarkia, a result concordant with preliminary cladistic analysis of morphological and isozymic characters. The monophyletic nature of sections encompassing the PGI [phosphoglucose isomerase] gene duplication is not rejected or supported by this cpDNA restriction site analysis. Preliminary DNA restriction fragment analysis for the nine previously described sections of Fuchsia and one new section is presented and then compared with published biogeographical, fossil, morphological, and cytological results. The preliminary chloroplast DNA analysis in Fuschia indicates that the disjunct Old World sect. Skinnera was the first lineage to diverge, followed by the monotypic Central American sect. Jimenesia. The phylogenetic relationships of the other sections of Fuchsia remain unclear. Comparisons of systematic results using cpDNA restriction site variability and morphological, cytological, and isozymic variability are reviewed for the Onagraceae and other angiosperms.