Sex Chromosome Mosaicism and Hybrid Speciation among Tiger Swallowtail Butterflies
(A) Population clustering of AFLP data in STRUCTURE under the assumption of two, three and four populations, comparing appalachiensis with laboratory-generated glaucus x canadensis hybrids. (B) appalachiensis AFLP allele frequencies with respect to glaucus and canadensis, based on species pair-wise locus-by-locus AMOVAs. Allele frequencies of “glaucus-like” AFLPs were significantly different from canadensis, “canadensis-like” AFLPs were significantly different from glaucus, “intermediate” were intermediate between glaucus and canadensis but significantly different from neither, and “different” were significantly different from both glaucus and canadensis. (C) Population clustering in STRUCTURE under the assumption of four populations, showing genomic similarity between the laboratory-generated hybrids and late flight canadensis, and distinctiveness of appalachiensis (also see Figure S2). For (A) and (C), admixture proportions of the sampled individuals, rather than their assignment probabilities, are shown.