Publications

genetic basis of reduced eyes in the hybrids of drosophila virilis phylad species.	structural anomalies were detected in f1 and backcross hybrids of drosophila virilis and three of its sibling species drosophila novamexicana, drosophila americana texana and drosophila americana americana. similar but not identical anomalies have been described in d. virilis x d. lummei hybrids. f1 (d. virilis x d. novamexicana) hybrids had only slight disorders in the abdominal cuticula, but 5.3% of the first backcross generation hybrids had reduced eyes. eye defects in the second generation w ...	1992	1295856
vitellogenetic defects in hybrids of the species pair drosophila virilis and drosophila texana.	in interspecific matings between the species drosophila virilis and drosophila texana, female sterility can be observed in f2 backcross females and in f2 hybrid females. the results presented in this report show that the female sterility, whenever it exists, is due to prevention of vitellogenin synthesis in the fat body, but other abnormalities such as defects with the hybrid ovaries are not excluded. the observation that sterility appears among females from backcrosses suggests that incompatibi ...	1996	8754280
incompatibilities between y chromosome and autosomes are responsible for male hybrid sterility in crosses between drosophila virilis and drosophila texana.	crosses between drosophila virilis and d. texana produce viable and fertile f1 males and females. when f1 males are backcrossed to either parental species they also produced fertile sons. however, about one-third of f1 males carrying the d. texana y chromosome are sterile. when fertile f1 males with the d. texana y chromosome are crossed to d. virilis, about three quarters of the sons are sterile. we show that these sterilities result from incompatibilities between the d. texana y chromosome and ...	1996	8801221
ovarian defects in hybrids of the species pair drosophila virilis and drosophila texana.	in interspecific matings between drosophila virilis and drosophila texana female sterility is observed in f2 hybrid females. a previous study has shown that no vitellogenin synthesis occurs in the fat body of sterile hybrid females. the results presented in this paper show that hybrid ovaries of sterile females transplanted into the abdomens of females of the parental species are not able to develop upon maturity. with few exceptions, the hybrid ovaries remained alive in the host environment, bu ...	1997	9094211
chromosomal and allelic variation in drosophila americana: selective maintenance of a chromosomal cline.	geographically structured genetic variation, as represented by clines and hybrid zones, offers unique opportunities to study adaptation and speciation in natural populations. a hybrid zone has been reported between drosophila americana americana and drosophila americana texana, two taxa that are distinguished solely by the arrangement of their x and 4th chromosomes. in this study, samples of d. americana were collected along a latitudinal transect across the inferred hybrid zone, and the frequen ...	2002	11908655
patterns of microsatellite variation through a transition zone of a chromosomal cline in drosophila americana.	chromosomal rearrangements have been considered as important barriers to gene flow and were often used in the delineation of species. the original taxonomic designation of drosophila americana americana and drosophila americana texana is based on the presence/absence of a centric fusion between the x- and fourth chromosomes. d. a. americana presents the derived fused state, whereas drosophila a. texana presents the freely segregating ancestral state. the degree of genetic separation between the ...	2006	16823404
inferring the evolutionary history of drosophila americana and drosophila novamexicana using a multilocus approach and the influence of chromosomal rearrangements in single gene analyses.	the evolutionary history of closely related organisms can prove sometimes difficult to infer. hybridization and incomplete lineage sorting are the main concerns; however, genome rearrangements can also influence the outcome of analyses based on nuclear sequences. in the present study, dna sequences from 12 nuclear genes, for which the approximate chromosomal locations are known, have been used to estimate the evolutionary history of two forms of drosophila americana (drosophila americana america ...	2008	18482259
an x chromosome effect responsible for asymmetric reproductive isolation between male drosophila virilis and heterospecific females.	reproductive isolation between closely related species is expressed through uncoordinated courtship, failed fertilization, and (or) postzygotic barriers. behavioural components of mating often form an initial barrier to hybridization between species. in many animals, females are responsible for mating discrimination in both intra- and interspecific crosses; males of drosophila virilis group represent an exception to this trend. using overall productivity tests, we show that a lower proportion of ...	2009	19132071