A Comparison of Multivariate Methods for the Detection of Hybridization

Abstract

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Study of natural hybridization between Alnus incana (L.) Moench. and Alnus glutinosa (L.) Gaertn.

“…The method of major components applied in the study of plan natural hybridization (Adams 1982;Wilson 1992, and others) was used for the identification of spontaneous hybrids and the analysis of their variation.…”

A multivariate analysis of introgression betweenQuercus roburandQ. petraeain The Netherlands

“…the F I weighted Wells' distance diagram (Adams 1982). Although useful results have been obtained with this method, e.g.…”

On inferring hybridity from morphological intermediacy

“…Principal components, hybrid indices, and similar methods may be useful in analyzing introgression and swarm structure after one has already demonstrated that hybridization is involved to begin with. Unfortunately, methodological papers on this topic have not made it clear that the methods for showing introgression or swarm structure are not acceptable for showing hybridity itself, and that before even trying to show introgression or swarm structure it is necessary to first show hybridity (e.g., Anderson, 1949;Hatheway, 1962;Namkoong, 1966;Wells, 1980;Pimentel, 1981;Adams, 1982;Brockmann, 1987).…”