title: Chromosomal evolution of sibling species of the Drosophila willistoni group. I. Chromosomal arm IIR (Muller's element B).
abstract: The phylogenetic relationships among nine entities of Drosophila belonging to the D. willistoni subgroup were investigated by establishing the homologous chromosomal segments of IIR chromosome, Muller's element B (equivalent to chromosome 2L of D. melanogaster). The sibling species of the D. willistoni group investigated include D. willistoni, D. tropicalis tropicalis, D. tropicalis cubana, D. equinoxialis, D. insularis and four semispecies of the D. paulistorum complex. The phylogenetic relationships were based on the existence of segments in different triads of species, which could only be produced by overlapping inversions. Polytene banding similarity maps and break points of inversions between species are presented. The implications of the chromosomal data for the phylogeny of the species and comparisons with molecular data are discussed. The aim of this study is to produce phylogenetic trees depicting accurately the sequence of natural events that have occurred in the evolution of these sibling species.
authors.affiliation: Departamento de Genética, Instituto de Biociências, Universidade Federal do Rio Grande do Sul (UFRGS), Caixa Postal 15053, CEP 91501-970, Porto Alegre, RS, Brazil. claudiarohde@yahoo.com
authors.forename: Claudia
authors.initials: C
authors.lastname: Rohde
authors.forename: Ana Cristina Lauer
authors.initials: AC
authors.lastname: Garcia
authors.forename: Victor Hugo
authors.initials: VH
authors.lastname: Valiati
authors.forename: Vera Lúcia S
authors.initials: VL
authors.lastname: Valente
mesh_terms: D000818:Animals; D005075:Biological Evolution; D002874:Chromosome Mapping; D002875:Chromosomes / Q000235:genetics*; D004330:Drosophila / Q000235:genetics*; D010802:Phylogeny