Under the canonical model, sex chromosomes began as a pair of homologous chromosomes that were identical except that one chromosome had a sex-determining locus SL that the other lacked 36079 — 82 see Fig. The males and females in different dioecious species might therefore evolve via sterility mutations at many different loci, restricted only by pleiotropic effects that preclude some loci from being involved in naturally evolved unisexuality.
AFLPs are reliable for phylogenetic reconstruction and, in fact, provide answers consistent with other sources of data in addition to being able to resolve relationships how sex chromosomes are inherited in West Jordan DNA sequence data cannot  — . We mapped on this phylogeny the ecological and morphological traits Table S6 relevant to the hybrid phenotype of appalachiensis using the software MacClade 4 .
Published : 03 May
Pair-wise population differentiation among tiger swallowtails based on AFLP data. From Wikipedia, the free encyclopedia. J Ethol 25— The hybrid zone how sex chromosomes are inherited in West Jordan maintained by thermal ecology: glaucus is adapted to a how sex chromosomes are inherited in West Jordan thermal habitat compared to canadensis.
Our work also highlights specific areas where additional data will enrich our understanding of this system in particular and the dynamics of hybrid speciation in general. Mercader RJ, Scriber JM Asymmetrical thermal constraints on the parapatric species boundaries of two widespread generalist butterflies.
On the other hand, in B-carrying individuals an increased chiasma formation among autosomes is often observed John and Hewitt, ; Patton, ; Camacho et al,perhaps leading to genetic rearrangements resistant to B-chromosome action Harvey, Hybridization between two species may sometimes lead to the formation of a third species.
We used the software DnaSP  to count the total number of polymorphisms and the subset that were species-specific for each species at each gene.
Therefore, 10 males and 10 females from each B. In: Seward AC, editor. The mechanism of sex determination in dioecious plants.
Therefore, 10 males and 10 females from each B. The results Table 2 indicate that the high male ratio is strictly paternally inherited, more specifically through some fathers rather than through all males. Table S1 lists details of the wild-caught individuals and 23 laboratory-generated hybrids used for genetic analysis, and Figure S5 shows localities where these specimens were collected.
We thank Jeff Demuth and Daven Presgraves for graciously supplying us with prepublication manuscripts and for insightful comments on an early draft of this manuscript. B Ecological and morphological differentiation between glaucus and canadensis , and their admixture in appalachiensis  —  also see Figure S1.
Chromosomal redistribution of male-biased genes in mammalian evolution with two bursts of gene gain on the X chromosome.