| interorder transfer of mycoplasmalike microorganisms between drosophila paulistorum and ephestia kühniella. ii. numbers of mlo and sterility. | a successful attempt was made to culture the mycoplasmalike microorganism causing semispecific hybrid male sterility in drosophila paulistorum utilizing ephestia kühniella as the intermediate host. data gleaned from this passage indicates that the induction of sterility depends upon the quality not the quantity of infectious intracellular symbionts. | 1977 | 923700 |
| pole cells of drosophila paulistorum: embryologic differentiation with symbionts. | the pole cells of young d. paulistorum embryos are destined to form the germinal cells of both male and female imagoes. in addition, specialized portions of the midgut may be derived from pole cell progenitors. in this initial study of their embryogenesis by means of electron microscopy, various stages of pole cell development are shown in both non-hybrid (potentially fertile) and intersemispecific hybrid (potentially sterile as males) materials. originally, approximately 5 or 6 cells emerge to ... | 1975 | 1167128 |
| embryonic pole cells and mycoplasmalike symbionts in drosophila paulistorum. | | 1974 | 4211979 |
| population genetics in the american topics. vi. a comparative study of the courtship behavior in four semispecies of drosophila paulistorum. | | 1972 | 5048148 |
| a study of infectious hybrid sterility in drosophila paulistorum. | | 1967 | 5231599 |
| induction of sterility in drosophila paulistorum: effect of cytoplasmic factors. | male hybrids from mesitas and santa marta (colombia) strains of drosophila paulistorum are sterile. homogenates of males belonging to these strains and from the hybrids were injected into mesitas or santa marta females, which were crossed to males of their own strains, so that their progenies were genetically nonhybrid. nevertheless, some of the males from these progenies were sterile. male progenies of females that were injected with homogenates from males that disagreed in the source of cytopl ... | 1971 | 5289375 |
| an electron microscopic study of the etiology of hybrid sterility in drosophila paulistorum. i. mycoplasma-like inclusions in the testes of sterile males. | | 1970 | 5436404 |
| antimycoplasmal antibiotics and hybrid sterility in drosophila paulistorum. | male hybrids between the santa marta and mesitas strains of drosophila paulistorum are sterile. the sterility can be partially alleviated by treatment of the santa marta mothers with the antimycoplasmal antibiotics tylosin tartrate and tetracycline hydrochloride. the proportions of hybrid males in which there are mature motile spermatozoa are higher in the progenies of drug-treated mothers than in the controls. electron microscopy reveals mycoplasma-like bodies in the untreated controls, but not ... | 1970 | 5450357 |
| induction by streptococcal l-forms of two reproductive isolating mechanisms in drosophila paulistorum. | the six semispecies of the drosophila paulistorum complex do not normally interbreed, but when hybrids are produced in the laboratory, the males are sterile. in earlier work, cytoplasmic components responsible for this sterility had been transferred by injection of streptococcal l-forms isolated from the mesitas and santa marta flies. to extend these findings, and l-form from the centro-american flies was injected into three semispecies. transfer of l-form from one semispecies to another resulte ... | 1984 | 6439676 |
| streptococcal l-forms isolated from drosophila paulistorum semispecies cause sterility in male progeny. | the drosophila paulistorum complex contains six semispecies that do not normally interbreed. in the laboratory, crosses between semispecies produce fertile daughters and sterile sons. microbial endosymbionts have been observed in all d. paulistorum flies that display this male sterility. streptococcal l-forms have been isolated from the andean-brazilian (mesitas) and transitional (santa marta) semispecies and cultured in artificial medium. transfer of these l-forms from their native hosts into r ... | 1984 | 6582483 |
| bacterial entomopathogens from the drosophila paulistorum semispecies complex. | bacteria which are infectious by inoculation in lepidoptera have been isolated and characterized from semispecies comprising the drosophila paulistorum complex. these microorganisms are pathogenic toward lepidopteran hosts such as heliothis virescens when introduced by injection of drosophila tissue extracts and have been given the trivial name dple (d. paulistorum lepidopteran entomopathogen). the dple from two of the semispecies, transitional and andean, were determined to be related to proteu ... | 1995 | 7722340 |
| characteristics of the drosophila paulistorum male sterility agent in a secondary host, ephestia kuehniella. | crosses among the six semispecies of drosophila paulistorum produce sterile male hybrids. this sterility is caused by an agent which has characteristics of a microorganism. it is pathogenic in a secondary host, the larvae of the mediterranean meal moth, ephestia kuehniella, and can be serially passaged in ephestia, where it is lethal. the agent was passaged back into d. paulistorum, where it induced sterility in males of a semispecies different from that of origin of the agent. infectious partic ... | 1981 | 16345886 |
| infectious speciation revisited: impact of symbiont-depletion on female fitness and mating behavior of drosophila paulistorum. | the neotropical drosophila paulistorum superspecies, consisting of at least six geographically overlapping but reproductively isolated semispecies, has been the object of extensive research since at least 1955, when it was initially trapped mid-evolution in flagrant statu nascendi. in this classic system females express strong premating isolation patterns against mates belonging to any other semispecies, and yet uncharacterized microbial reproductive tract symbionts were described triggering hyb ... | 2010 | 21151959 |
| sequences homologous to p elements occur in drosophila paulistorum. | p elements, a class of mobile genetic elements that cause hybrid dysgenesis in drosophila melanogaster, have thus far been shown to occur only in this species. using whole genome blot analysis, we present evidence which indicates that sequences homologous to d. melanogaster p elements also occur in drosophila paulistorum, a distant relative. d. paulistorum is considered a species complex, consisting of six known incipient species or semispecies. all six semispecies possess p element homologous s ... | 1984 | 6093120 |
| reevaluating the infection status by the wolbachia endosymbiont in drosophila neotropical species from the willistoni subgroup. | infections by the endosymbiotic bacterium wolbachia developed a rapid global expansion within old world drosophila species, ultimately infecting also neotropical species. in this sense, screenings are necessary to characterize new variants of wolbachia or new hosts, and also in order to map the dynamics of already known infections. in this paper, we performed a double screening approach that combined dot-blot and pcr techniques in order to reevaluate the infection status by wolbachia in species ... | 2013 | 23906981 |
| developmental isolation and subsequent adult behavior of drosophila paulistorum. v. survey of six sibling species. | in an investigation into the effects of developmental isolation from all conspecifics, the drosophila willistoni group of six sibling species responded to differing degrees: all six are reproductively isolated from d. paulistorum, the tester species. drosophila pavlovskiana, a narrow endemic, proved the most vulnerable, responding by reducing its adult sexual isolation, if eggs, any instar, and sometimes even pupae were socially isolated. to lesser degrees, d. tropicalis and d. willistoni both p ... | 1999 | 10371760 |
| enzyme variability in the drosophila willistoni group. 3. amounts of variability in the superspecies, d. paulistorum. | the semispecies composing the superspecies, drosophila paulistorum, have been analyzed for genetic variation at 17 enzyme loci. on the average a population of d. paulistorum is polymorphic for 55-67% of its loci and an average individual is heterozygous at 21% of its loci. the pattern of genetic variability found supports the hypothesis that allozyme variation is maintained in natural populations by some form of balancing selection. evidence is presented which supports the hypothesis that glucos ... | 1972 | 5013892 |
| interracial hybridization and breakdown of coadapted gene complexes in drosophila paulistorum and drosophila willistoni. | | 1958 | 16590252 |
| maternally inherited "sex-ratio" conditions in drosophila willistoni and drosophila paulistorum. | | 1958 | 17247756 |
| combining morphology and molecular data to improve drosophila paulistorum (diptera, drosophilidae) taxonomic status. | the willistoni species subgroup has been the subject of several studies since the latter half of the past century and is considered a neotropical model for evolutionary studies, given the many levels of reproductive isolation and different evolutionary stages occurring within them. here we present for the first time a phylogenetic reconstruction combining morphological characters and molecular data obtained from 8 gene fragments (coi, coii, cytb, adh, ddc, hb, kl-3 and per). some relationships w ... | 2018 | 29355090 |
| restricted distribution and lateralization of mutualistic wolbachia in the drosophila brain. | microbial symbionts are universal entities of all living organisms that can significantly affect host fitness traits in manifold ways but, even more fascinating, also their behaviour. although better known from parasitic symbionts, we currently lack any cases where 'neurotrophic' symbionts have co-evolved mutualistic behavioural interactions from which both partners profit. by theory, most mutualistic associations have originated from ancestral parasitic ones during their long-term co-evolution ... | 2017 | 27353950 |
| male-specific cuticular compounds of the six drosophila paulistorum semispecies: structural identification and mating effect. | we have identified cuticular pheromones that sustain the integrity of the six drosophila paulistorum semispecies. hexane extracts of male and female cuticles were separated on a silica gel column and analyzed using gas chromatography/mass spectrometry. both sexes of each of the six semispecies have the same fifteen major cuticular components, all hydrocarbons ranging from c31 to c37. however, all males have four additional ester compounds. bioassay observations showed that this four-component es ... | 2010 | 20694528 |
| developmental isolation and subsequent adult behavior of drosophila paulistorum. vi. quantitative variation in cuticular hydrocarbons. | our previous studies have demonstrated that long-term chemical contact with heterospecifics during development minimized unproductive heterospecific matings among the six drosophila paulistorum semispecies. when socially isolated from conspecifics, discrimination significantly decreased so that more ultimately unproductive heterospecific matings occurred. such results suggest that learning and social experiences play roles in mate recognition, using chemical information. in investigations into t ... | 2004 | 15082936 |
| developmental isolation and subsequent adult behavior of drosophila paulistorum. iv. courtship. | early social experiences play important roles in adult drosophila paulistorum mate selection. differences in courtship between control males and wholly socially isolated males were observed in chambers. socially isolated males displayed more courtship toward virgin females than did controls. socially isolated males were more successful in competing for mates. yet socially isolated males from all six semispecies also displayed notable frequencies of homosexual behavior. | 1998 | 9573647 |
| developmental isolation and subsequent adult behavior of drosophila paulistorum. iii. alternative rearing. | we have been utilizing members of the drosophila paulistorum complex of semispecies to study the development of adult discriminatory behavior. in this study, three rearing methods were used to examine the effects of previous exposure to heterosemispecifics on reproductive isolation among the various semispecies. experimental flies were exposed to heterosemispecifics by one of three methods: exposure to airborne heterosemispecific stimuli from egg through sexual maturity, physical contact with he ... | 1996 | 8852729 |
| developmental isolation and subsequent adult behavior of drosophila paulistorum. ii. prior experience. | preadult seclusion imposed upon members of the drosophila paulistorum complex of intersterile semispecies significantly decreased sexual isolation between adults of the semispecies. while seclusion at any developmental stage had this effect, there were quantitative variations correlated with the stage at which seclusion had been initiated: the earlier the stage at which seclusion began, the more frequent were the heterogamic matings. all the stages of development seemed to contribute to final ad ... | 1996 | 8852728 |
| developmental isolation and subsequent adult behavior of drosophila paulistorum. i. survey of the six semispecies. | we present results deriving from the inception of an investigation (involving 4,000 scored matings) into the development of discriminatory behavior in drosophila paulistorum. we examined two complementary situations for their effects on mating behavior: physical isolation (seclusion) beginning at each of six developmental stages and exposure to heterosemispecifics during all preadult stages (mixed culturing). preadult seclusion at certain stages decreased sexual isolation between three of four s ... | 1992 | 1417679 |
| modes of selection maintaining an inversion polymorphism in drosophila paulistorum. | the possibility that fitness relationships associated with an inversion polymorphism in d. paulistorum were frequency dependent was investigated. using allozymes of tetrazolium oxidase to mark inversions, the effects of genotype frequency, larval density, and culture conditions on fitness were assessed. the proportions of genotypes among egg-laying females were varied, thus changing the expected proportions of progeny produced in the absence of fecundity or viability selection. the genotypes of ... | 1978 | 17248800 |
| genetic differentiation within the andean semispecies of drosophila paulistorum. | | 1976 | 28563337 |
| partially successful attempt to enhance reproductive isolation between semispecies of drosophila paulistorum. | | 1976 | 28563045 |
| ethological isolation and mating experience in drosophila paulistorum. | with few exceptions, previously published experiments documenting ethological isolation between drosophila populations have used young virgin females. we have observed directly females of drosophila paulistorum semispecies in choice experiments with both homogamic and heterogamic males. aged females' sexual selection did not differ from that of young females. previous heterogamic copulatory experience did not change the degree of sexual isolation; however, females with homogamic copulatory exper ... | 1976 | 1062812 |
| unstable intermediates between orinocan and interior semispecies of drosophila paulistorum. | | 1975 | 28555854 |
| the incidence of repeated mating in the superspecies, drosophila paulistorum. | | 1974 | 4833668 |
| flounder effects and linkage disequilibria in experimental populations of drosophila. | six laboratory populations of drosophila paulistorum were examined for changes in gene frequencies at an enzyme locus, tetrazolium oxidase (to). in some of the populations, the alleles were introduced on over 100 independently derived chromosomes. these populations showed considerable stability in gene frequencies although they were at widely different starting frequencies. other populations were begun with only a few (about 6) independently derived chromosomes. these populations showed signific ... | 1974 | 4525457 |
| population genetics in the american tropics vii. the courtship behavior of drosophila paulistorum cluster of species. | | 1973 | 4788928 |
| genetic similarities and evolutionary relationships among the semispecies of drosophila paulistorum. | | 1972 | 28563359 |
| courtship interaction in the semispecies of drosophila paulistorum. | | 1972 | 28563059 |
| courtship behavior in the semispecies of the superspecies drosophila paulistorum. | | 1972 | 28555767 |
| mechanisms of male sterility in hybrids of the drosophila paulistorum group. | | 1971 | 5133085 |
| further studies of the etiology of hybrid male sterility in drosophila paulistorum. | | 1971 | 28563114 |
| geography of the sibling species related to drosophila willistoni, and of the semispecies of the drosophila paulistorum complex. | | 1971 | 28562939 |
| evidence of heterosis associated with an enzyme locus in a natural population of drosophila. | a wild population of drosophila paulistorum (andean semispecies) was analyzed by starch gel electrophoresis for a sex-linked enzyme locus, tetrazolium oxidase. the results of the analysis of f(1) progenies from 106 single female lines from são josé do rio prêto, brazil, has allowed us to determine the genotype of 106 wild-collected females and 104 wild-collected males. the population is polymorphic for two alleles with frequencies of 0.56 and 0.44. the observed frequencies among the females of t ... | 1970 | 5274455 |
| the interior semispecies of drosophila paulistorum. | | 1970 | 28562984 |
| a biometrical study on the semispecies of the drosophila paulistorum complex. | | 1970 | 28563005 |
| a cytological study on some recently collected strains of drosophila paulistorum. | | 1969 | 28562880 |
| transitional populations of drosophila paulistorum. | | 1969 | 28562925 |
| on the etiology of the sterility of hybrids between certain strains of drosophila paulistorum. | | 1969 | 5371014 |
| infectious hybrid sterility and the "new llanos" strain of drosophila paulistorum. | | 1968 | 5677426 |
| unusual filamentous structures in the paragonia of male drosophila. | drosophila paulistorum is a complex of five incipient species which when crossed produce sterile hybrid males and fertile females. sterility of the male progeny can sometimes be induced by injecting females of one strain (mesitas) with a homogenate of males of another strain (santa marta) or of hybrids between these strains, and then crossing the recipient females to mesitas males. filamentous structures have been found in cytoplasmic vacuoles in paragonial cells in males of these and other simi ... | 1968 | 5664207 |
| antibiotics and infections hybrid sterility in drosophila paulistorum. | | 1968 | 5713660 |
| induction of hybrid sterility in nonhybrid males of drosophila paulistorum. | | 1967 | 6067757 |
| experiments on the incipient species of the drosophila paulistorum complex. | | 1967 | 6031598 |
| a comparative study of the chromosomal polymorphs in the incipient species of the drosophila paulistorum complex. | | 1967 | 5594787 |
| spontaneous origin of an incipient species in the drosophila paulistorum complex. | | 1966 | 5219677 |
| a comparative chromosome study in the incipient species of the drosophila paulistorum complex. | | 1966 | 5958571 |
| transmission by injection of hybrid sterility to nonhybrid males in drosophila paulistorum: preliminary report. | | 1965 | 5217437 |
| on the nature of the transitional strains in drosophila paulistorum. | | 1964 | 14128128 |
| the superspecies drosophila paulistorum. | | 1964 | 14104602 |
| apparent cytoplasmic sterility in drosophila paulistorum. | | 1963 | 16591045 |
| races and incipient species in drosophila paulistorum. | | 1962 | 17745923 |
| a new type of hybrid sterility in drosophila paulistorum. | | 1962 | 13889536 |
| the transitional races of drosophila paulistorum: a study of hybrid sterility. | | 1962 | 13889537 |
| a comparative study of the chromosomes in the incipient species of the drosophila paulistorum complex. | | 1962 | 14028272 |
| the genetics of sexual isolation in drosophila paulistorum. | | 1961 | 13726033 |
| a genetic constitution frustrating the sexual drive in drosophila paulistorum. | hybrids obtained in the laboratory between two subspecies of drosophila paulistorum possess a genetic constitution which is discordant enough so that the hybrid females repel the courtship of all males, and will mate with none. the hybrid males will court and will be rejected by almost all females, including their own hybrid siblings. | 1960 | 13819623 |
| drosophila paulistorum, a cluster of species in statu nascendi. | | 1959 | 16590403 |