Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| the role of species-specific sensory cues in male responses to mating rivals in drosophila melanogaster fruitflies. | complex sets of cues can be important in recognizing and responding to conspecific mating competitors and avoiding potentially costly heterospecific competitive interactions. within drosophila melanogaster, males can detect sensory inputs from conspecifics to assess the level of competition. they respond to rivals by significantly extending mating duration and gain significant fitness benefits from doing so. here, we tested the idea that the multiple sensory cues used by d. melanogaster males to ... | 2017 | 29187965 |
| gut microbiomes and reproductive isolation in drosophila. | experimental studies of the evolution of reproductive isolation (ri) in real time are a powerful way in which to reveal fundamental, early processes that initiate divergence. in a classic speciation experiment, populations of drosophila pseudoobscura were subjected to divergent dietary selection and evolved significant positive assortative mating by diet. more recently, a direct role for the gut microbiome in determining this type of ri in drosophila melanogaster has been proposed. manipulation ... | 2017 | 29109277 |
| genomics of natural populations: evolutionary forces that establish and maintain gene arrangements in drosophila pseudoobscura. | the evolution of complex traits in heterogeneous environments may shape the order of genes within chromosomes. drosophila pseudoobscura has a rich gene arrangement polymorphism that allows one to test evolutionary genetic hypotheses about how chromosomal inversions are established in populations. d. pseudoobscura has >30 gene arrangements on a single chromosome that were generated through a series of overlapping inversion mutations with >10 inversions with appreciable frequencies and wide geogra ... | 2017 | 29055159 |
| "sex-ratio" trait, sex composition, and relative abundance in drosophila pseudoobscura. | 1982 | 28581105 | |
| temporal stability of third-chromosome inversion frequencies in drosophila persimilis and d. pseudoobscura. | 1992 | 28568997 | |
| postmating isolation analysis in founder-flush experimental populations of drosophila pseudoobscura. | 1996 | 28568951 | |
| selection and the "sex-ratio" polymorphism in natural populations of drosophila pseudoobscura. | "sex-ratio" (sr) is a naturally occurring x-linked meiotic drive system, where the sr-x chromosome is transmitted to nearly all progeny of sr males. it occurs at frequencies of up to 25% in some populations of drosophila pseudoobscura. because of the twofold drive advantage, sr should rapidly fix in populations, causing the extinction of the species, unless opposed by strong selection. i examine several of the adult components of fitness, including the frequencies of all genotypic mating combina ... | 1996 | 28568936 |
| founder-flush speciation in drosophila pseudoobscura: a large-scale experiment. | a founder-flush-crash model of speciation has been proposed that may particularly apply to island and other colonizations. previous laboratory experiments testing the model have given inconsistent results. we have conducted a large experiment with drosophila pseudoobscura designed to meet the essential postulates of the model and to separately test some of the postulates. forty-five experimental and 12 control populations have been studied during seven successive founder-flush-crash cycles, or a ... | 1993 | 28568735 |
| genetics of sexual isolation and courtship dysfunction in male hybrids of drosophila pseudoobscura and drosophila persimilis. | despite the importance of sexual isolation to speciation, few studies have analyzed the genetic basis of interspecific mating discrimination, particularly using hybrid males. in this study, i investigated the genetic basis of sexual isolation using male hybrids of drosophila pseudoobscura and d. persimilis. hybrid male mating success was caused by interactions between the x-chromosome and autosomes (or y-chromosome), and different arms of the x-chromosome contributed to mating success with femal ... | 1997 | 28568570 |
| laboratory evolution of epicuticular hydrocarbon composition and cuticular permeability in drosophila pseudoobscura: effects on sexual dimorphism and thermal-acclimation ability. | 1989 | 28568563 | |
| r- and k-selection in drosophila pseudoobscura. | 1980 | 28568469 | |
| population genetics of mexican drosophila vi. cytogenetic aspects of the inversion polymorphism in drosophila pseudoobscura. | 1979 | 28568185 | |
| sperm production and sterility in hybrids between two subspecies of drosophila pseudoobscura. | subspecies of drosophila pseudoobscura, one occurring in the united states and the other in bogota, columbia, exhibit haldane's rule in one direction of the cross. additionally, d. pseudoobscura produces two sperm types: short, sterile sperm and long, fertile, sperm. here i examine the relationship between the production of short and long sperm and hybrid sterility. fertile and sterile hybrid males produce a greater proportion of short sperm compared to parental males with sterile hybrids produc ... | 1998 | 28568153 |
| interspecific laboratory competition of the recently sympatric species drosophila subobscura and drosophila pseudoobscura. | -drosophila subobscura and d. pseudoobscura are closely related species coexisting on the west coast of north america, which was recently colonized by d. subobscura. in competition experiments with overlapping generations, d. subobscura is eliminated by d. pseudoobscura in a few generations at all four temperatures and two initial frequencies tested. yet in one-species cultures, d. subobscura thrives at all experimental conditions. single-generation competition experiments reveal lower survivors ... | 1998 | 28568145 |
| multiple mating and female fitness in drosophila pseudoobscura. | 1983 | 28568127 | |
| resource partitioning among genotypes of drosophila pseudoobscura. | 1983 | 28568031 | |
| modifiers and "sex ratio" in drosophila pseudoobscura. | 1978 | 28567934 | |
| a study of reaction norms in natural populations of drosophila pseudoobscura. | 1982 | 28567833 | |
| genetic divergence in closely related sibling species drosophila pseudoobscura, drosophila persimilis and drosophila miranda. | 1977 | 28567734 | |
| effects of age, rearing and mating experiences on frequency dependent sexual selection in drosophila pseudoobscura. | 1976 | 28565052 | |
| uniform heterokaryotypic superiority for viability in a colorado population of drosophila pseudoobscura. | 1968 | 28564814 | |
| genetic divergence in body size among experimental populations of drosophila pseudoobscura kept at different temperatures. | 1973 | 28564779 | |
| experiments on random genetic drift and natural selection in drosophila pseudoobscura. | 1966 | 28564754 | |
| morphological variation in natural and experimental populations of drosophila pseudoobscura and drosophila persimilis. | 1966 | 28564753 | |
| reproductive isolation as a consequence of adaptive divergence in drosophila pseudoobscura. | 1989 | 28564510 | |
| frequency-dependent mating in a modified allozyme locus of drosophila pseudoobscura. | 1979 | 28563948 | |
| viabilities of amylase genotypes in drosophila pseudoobscura on starch and maltose food. | in order to study the relationship between selection on an enzyme and the environment, viability was measured for genotypes at the α-amylase (amy) locus of d. pseudoobscura on food containing either starch as the primary source of carbohydrates or, as a control, maltose, the breakdown product of starch by amylase. these conditions were chosen to reveal possible differences among these genotypes in their abilities to survive on starch food. counted numbers of larvae were cultured on food with low ... | 1987 | 28563764 |
| mating pattern and mating success of drosophila pseudoobscura karyotypes in large experimental populations. | 1978 | 28563737 | |
| maintenance of chromosomal polymorphism in a population of drosophila pseudoobscura. ii. fecundity, longevity, viability and competitive fitness. | 1973 | 28563660 | |
| evolutionary divergence between two populations of drosophila pseudoobscura. | 1977 | 28563476 | |
| using frequency distributions to detect selection: inversion polymorphisms in drosophila pseudoobscura. | 1981 | 28563401 | |
| multiple mating and the "sex-ratio" trait in drosophila pseudoobscura. | 1981 | 28563371 | |
| chromosomal polymorphism in drosophila pseudoobscura used for diagnosis of geographic origin. | 1972 | 28563351 | |
| genetics of natural populations xlii. three decades of genetic change in drosophila pseudoobscura. | 1975 | 28563287 | |
| selection for mating activity in two chromosomal arrangements of drosophila pseudoobscura. | 1975 | 28563183 | |
| selection and inversion polymorphism in experimental populations of drosophila pseudoobscura initiated with the chromosomal constitutions of natural populations. | 1967 | 28563075 | |
| maintenante of chromosomal polymorphism in a population of drosophila pseudoobscura: viability under crowded and uncrowded conditions. | 1972 | 28563063 | |
| rigid and flexible chromosomal polymorphisms in neighboring populations of drosophila pseudoobscura. | 1974 | 28563030 | |
| genetics of natural populations. xxxviii. continuity and change in populations of drosophila pseudoobscura in western united states. | 1966 | 28562981 | |
| monthly frequency changes of drosophila pseudoobscura third chromosome gene arrangements in a california locality. | 1966 | 28562913 | |
| selection for and against ethological isolation between drosophila pseudoobscura and drosophila persimilis. | 1966 | 28562900 | |
| comparative studies of arrangements within and between populations of drosophila pseudoobscura. | 1966 | 28562896 | |
| population density and mating rates in drosophila pseudoobscura. | 1975 | 28555850 | |
| sperm predominance among drosophila pseudoobscura karyotypes. | 1984 | 28555808 | |
| genomic changes following the reversal of a y chromosome to an autosome in drosophila pseudoobscura. | robertsonian translocations resulting in fusions between sex chromosomes and autosomes shape karyotype evolution by creating new sex chromosomes from autosomes. these translocations can also reverse sex chromosomes back into autosomes, which is especially intriguing given the dramatic differences between autosomes and sex chromosomes. to study the genomic events following a y chromosome reversal, we investigated an autosome-y translocation in drosophila pseudoobscura. the ancestral y chromosome ... | 2017 | 28322435 |
| interspecific transgenic analysis of basal versus heat-shock-induced expression of a drosophila pseudoobscura hsp82-neo fusion gene in d. melanogaster. | drosophila melanogaster transformants containing a d. pseudoobscura hsp82-neo fusion gene were used to examine the relationship between chromosome structure and its variation to transcriptional activation and gene expression. at normal temperatures (25° c) transgenic hsp82-neo was transcribed in diffuse polytene chromosomal bands encoding antibiotic g418-resistance without intensive puff formation. substantial basal expression of the transgene was observed in all tissues examined: salivary gland ... | 1994 | 28305933 |
| remating responses are consistent with male postcopulatory manipulation but not reinforcement in d. pseudoobscura. | reinforcement occurs when hybridization between closely related lineages produces low-fitness offspring, prompting selection for elevated reproductive isolation specifically in areas of sympatry. both premating and postmating prezygotic behaviors have been shown to be the target of reinforcing selection, but it remains unclear whether remating behaviors experience reinforcement, although they can also influence offspring identity and limit formation of hybrids. here, we evaluated evidence for re ... | 2017 | 28116047 |
| we also canfly! the 2nd mexfly drosophila research conference. | the 2nd mexican drosophila research conference (mexfly) took place on june 30th and july 1st, 2016 in mexico city, at the center for research and advanced studies of the national polytechnic institute (cinvestav). principal investigators, postdocs, students, and technicians from drosophila labs across mexico attended. the guest speaker was chris rushlow from new york university, who presented work on zelda, a key transcriptional activator of the early zygotic genome. here we provide a brief repo ... | 2016 | 27960619 |
| mistaken identity: another bias in the use of relative genetic divergence measures for detecting interspecies introgression. | measures of genetic divergence have long been used to identify evolutionary processes operating within and between species. however, recent reviews have described a bias in the use of relative divergence measures towards incorrectly identifying genomic regions that are seemingly immune to introgression. here, we present a novel and opposite bias of relative divergence measures: misidentifying regions of introgression between sister species. we examine two distinct haplotypes of intermediate freq ... | 2016 | 27760228 |
| hubby and lewontin on protein variation in natural populations: when molecular genetics came to the rescue of population genetics. | the 1966 genetics papers by john hubby and richard lewontin were a landmark in the study of genome-wide levels of variability. they used the technique of gel electrophoresis of enzymes and proteins to study variation in natural populations of drosophila pseudoobscura, at a set of loci that had been chosen purely for technical convenience, without prior knowledge of their levels of variability. together with the independent study of human populations by harry harris, this seminal study provided t ... | 2016 | 27516612 |
| union of phylogeography and landscape genetics. | phylogeography and landscape genetics have arisen within the past 30 y. phylogeography is said to be the bridge between population genetics and systematics, and landscape genetics the bridge between landscape ecology and population genetics. both fields can be considered as simply the amalgamation of classic biogeography with genetics and genomics; however, they differ in the temporal, spatial, and organismal scales addressed and the methodology used. i begin by briefly summarizing the history a ... | 2016 | 27432989 |
| genomics of natural populations: how differentially expressed genes shape the evolution of chromosomal inversions in drosophila pseudoobscura. | chromosomal rearrangements can shape the structure of genetic variation in the genome directly through alteration of genes at breakpoints or indirectly by holding combinations of genetic variants together due to reduced recombination. the third chromosome of drosophila pseudoobscura is a model system to test hypotheses about how rearrangements are established in populations because its third chromosome is polymorphic for >30 gene arrangements that were generated by a series of overlapping invers ... | 2016 | 27401754 |
| comparative expression dynamics of intergenic long noncoding rnas in the genus drosophila. | thousands of long noncoding rnas (lncrnas) have been annotated in eukaryotic genomes, but comparative transcriptomic approaches are necessary to understand their biological impact and evolution. to facilitate such comparative studies in drosophila, we identified and characterized lncrnas in a second drosophilid-the evolutionary model drosophila pseudoobscura using rna-seq and computational filtering of protein-coding potential, we identified 1,589 intergenic lncrna loci in d. pseudoobscura we su ... | 2016 | 27189981 |
| temperature can shape a cline in polyandry, but only genetic variation can sustain it over time. | multiple mating by females (polyandry) is a widespread behavior occurring in diverse taxa, species, and populations. polyandry can also vary widely within species, and individual populations, so that both monandrous and polyandrous females occur together. genetic differences can explain some of this intraspecific variation in polyandry, but environmental factors are also likely to play a role. one environmental factor that influences many fundamental biological processes is temperature. higher t ... | 2017 | 27004012 |
| sexual selection and assortative mating: an experimental test. | mate choice and mate competition can both influence the evolution of sexual isolation between populations. assortative mating may arise if traits and preferences diverge in step, and, alternatively, mate competition may counteract mating preferences and decrease assortative mating. here, we examine potential assortative mating between populations of drosophila pseudoobscura that have experimentally evolved under either increased ('polyandry') or decreased ('monogamy') sexual selection intensity ... | 2016 | 26970522 |
| winter is coming: hibernation reverses the outcome of sperm competition in a fly. | sperm commonly compete within females to fertilize ova, but research has focused on short-term sperm storage: sperm that are maintained in a female for only a few days or weeks before use. in nature, females of many species store sperm for months or years, often during periods of environmental stress, such as cold winters. here we examine the outcome of sperm competition in the fruit fly drosophila pseudoobscura, simulating the conditions in which females survive winter. we mated females to two ... | 2016 | 26565889 |
| recombining without hotspots: a comprehensive evolutionary portrait of recombination in two closely related species of drosophila. | meiotic recombination rate varies across the genome within and between individuals, populations, and species in virtually all taxa studied. in almost every species, this variation takes the form of discrete recombination hotspots, determined in some mammals by a protein called prdm9. hotspots and their determinants have a profound effect on the genomic landscape, and share certain features that extend across the tree of life. drosophila, in contrast, are anomalous in their absence of hotspots, p ... | 2015 | 26430062 |
| krüppel expression levels are maintained through compensatory evolution of shadow enhancers. | many developmental genes are controlled by shadow enhancers—pairs of enhancers that drive overlapping expression patterns. we hypothesized that compensatory evolution can maintain the total expression of a gene, while individual shadow enhancers diverge between species. to test this hypothesis, we analyzed expression driven by orthologous pairs of shadow enhancers from drosophila melanogaster, drosophila yakuba, and drosophila pseudoobscura that control expression of krüppel, a transcription fac ... | 2015 | 26344774 |
| temporal stability of molecular diversity measures in natural populations of drosophila pseudoobscura and drosophila persimilis. | many molecular ecological and evolutionary studies sample wild populations at a single point in time, but that data represents genetic variation from a potentially unrepresentative snapshot in time. variation across time in genetic parameters may occur quickly in species that produce multiple generations of offspring per year. here, we compare genetic diversity in wild caught populations of drosophila persimilis and drosophila pseudoobscura collected 16 years apart at the same time of year and s ... | 2017 | 25969560 |
| opposite environmental and genetic influences on body size in north american drosophila pseudoobscura. | populations of a species often differ in key traits. however, it is rarely known whether these differences are associated with genetic variation and evolved differences between populations, or are instead simply a plastic response to environmental differences experienced by the populations. here we examine the interplay of plasticity and direct genetic control by investigating temperature-size relationships in populations of drosophila pseudoobscura from north america. we used 27 isolines from t ... | 2015 | 25887658 |
| assessment of rival males through the use of multiple sensory cues in the fruitfly drosophila pseudoobscura. | environments vary stochastically, and animals need to behave in ways that best fit the conditions in which they find themselves. the social environment is particularly variable, and responding appropriately to it can be vital for an animal's success. however, cues of social environment are not always reliable, and animals may need to balance accuracy against the risk of failing to respond if local conditions or interfering signals prevent them detecting a cue. recent work has shown that many mal ... | 2015 | 25849643 |
| mating system variation drives rapid evolution of the female transcriptome in drosophila pseudoobscura. | interactions between the sexes are believed to be a potent source of selection on sex-specific evolution. the way in which sexual interactions influence male investment is much studied, but effects on females are more poorly understood. to address this deficiency, we examined gene expression in virgin female drosophila pseudoobscura following 100 generations of mating system manipulations in which we either elevated polyandry or enforced monandry. gene expression evolution following mating syste ... | 2014 | 25360260 |
| evidence for stabilizing selection on codon usage in chromosomal rearrangements of drosophila pseudoobscura. | there has been a renewed interest in investigating the role of stabilizing selection acting on genome-wide traits such as codon usage bias. codon bias, when synonymous codons are used at unequal frequencies, occurs in a wide variety of taxa. standard evolutionary models explain the maintenance of codon bias through a balance of genetic drift, mutation and weak purifying selection. the efficacy of selection is expected to be reduced in regions of suppressed recombination. contrary to observations ... | 2014 | 25326424 |
| faster-x effects in two drosophila lineages. | under certain circumstances, x-linked loci are expected to experience more adaptive substitutions than similar autosomal loci. to look for evidence of faster-x evolution, we analyzed the evolutionary rates of coding sequences in two sets of drosophila species, the melanogaster and pseudoobscura clades, using whole-genome sequences. one of these, the pseudoobscura clade, contains a centric fusion between the ancestral x chromosome and the autosomal arm homologous to 3l in d. melanogaster. this of ... | 2014 | 25323954 |
| can patterns of chromosome inversions in drosophila pseudoobscura predict polyandry across a geographical cline? | female multiple mating, known as polyandry, is ubiquitous and occurs in a wide variety of taxa. polyandry varies greatly from species in which females mate with one or two males in their lifetime to species in which females may mate with several different males on the same day. as multiple mating by females is associated with costs, numerous hypotheses attempt to explain this phenomenon. one hypothesis not extensively explored is the possibility that polyandrous behavior is captured and "fixed" ... | 2014 | 25247064 |
| a novel dataset for identifying sex-biased genes in drosophila. | phenotypic differences between males and females of sexually dimorphic species are caused in large part by differences in gene expression between the sexes, most of which occurs in the gonads. to accurately identify genes differentially expressed between males and females in drosophila, we sequenced the testis and ovary transcriptomes of d. yakuba, d. pseudoobscura, and d. ananassae and used them to identify sex-biased genes in the latter two species. we highlight the increased sensitivity and i ... | 2014 | 25031657 |
| evolution of divergent female mating preference in response to experimental sexual selection. | sexual selection is predicted to drive the coevolution of mating signals and preferences (mating traits) within populations, and could play a role in speciation if sexual isolation arises due to mating trait divergence between populations. however, few studies have demonstrated that differences in mating traits between populations result from sexual selection alone. experimental evolution is a promising approach to directly examine the action of sexual selection on mating trait divergence among ... | 2014 | 24931497 |
| the effects of inbreeding and ventilation on mating behavior in drosophila pseudoobscura. | two outbred and two inbred lines of drosophila pseudoobscura were used in mating behavior studies. for each line, mating rates were compared under both ventilated and nonventilated conditions. under nonventilated conditions courtship and mating were earlier, not following a random rate of occurence, and females mated after fewer courtships. flies from inbred lines tended to court and mate earlier. under all conditions a high proportion of matings occured on the first courtship attempt. | 1987 | 24925652 |
| does polyandry control population sex ratio via regulation of a selfish gene? | the extent of female multiple mating (polyandry) can strongly impact on the intensity of sexual selection, sexual conflict, and the evolution of cooperation and sociality. more subtly, polyandry may protect populations against intragenomic conflicts that result from the invasion of deleterious selfish genetic elements (sges). sges commonly impair sperm production, and so are likely to be unsuccessful in sperm competition, potentially reducing their transmission in polyandrous populations. here, ... | 2014 | 24695427 |
| the heritability of mating behaviour in a fly and its plasticity in response to the threat of sperm competition. | phenotypic plasticity is a key mechanism by which animals can cope with rapidly changeable environments, but the evolutionary lability of such plasticity remains unclear. the socio-sexual environment can fluctuate very rapidly, affecting both the frequency of mating opportunities and the level of competition males may face. males of many species show plastic behavioural responses to changes in social environment, in particular the presence of rival males. for example, drosophila pseudoobscura ma ... | 2014 | 24587294 |
| age-dependent male mating investment in drosophila pseudoobscura. | male mating investment can strongly influence fitness gained from a mating. yet, male mating investment often changes with age. life history theory predicts that mating investment should increase with age, and males should become less discriminatory about their mate as they age. understanding age-dependent changes in male behavior and their effects on fitness is important for understanding how selection acts in age-structured populations. although the independent effects of male or female age ha ... | 2014 | 24586373 |
| evidence that natural selection on codon usage in drosophila pseudoobscura varies across codons. | like other species of drosophila, drosophila pseudoobscura has a distinct bias toward the usage of c- and g-ending codons. previous studies have indicated that this bias is due, at least in part, to natural selection. codon bias clearly differs among amino acids (and other codon classes) in drosophila, which may reflect differences in the intensity of selection on codon usage. ongoing natural selection on synonymous codon usage should be reflected in the shapes of the site frequency spectra of d ... | 2014 | 24531731 |
| recent selection on the y-to-dot translocation in drosophila pseudoobscura. | the drosophila pseudoobscura dot chromosome acquired genes from the ancestral drosophila y chromosome in a y-to-dot translocation event that occurred between 12.7 and 20.8 ma. the formerly y-linked genes mostly retained their testis-specific expression but shrank drastically in size, mostly through intron reduction, since becoming part of the dot chromosome in this species. we investigated the impact of this translocation on the evolution of the both the y-to-dot translocated region and the orig ... | 2014 | 24390701 |
| intra-specific regulatory variation in drosophila pseudoobscura. | it is generally accepted that gene regulation serves an important role in determining the phenotype. to shed light on the evolutionary forces operating on gene regulation, previous studies mainly focused on the expression differences between species and their inter-specific hybrids. here, we use rna-seq to study the intra-specific distribution of cis- and trans-regulatory variation in drosophila pseudoobscura. consistent with previous results, we find almost twice as many genes (26%) with signif ... | 2013 | 24386226 |
| comparative gene expression analysis of dtg, a novel target gene of dpp signaling pathway in the early drosophila melanogaster embryo. | in the early drosophila melanogaster embryo, dpp, a secreted molecule that belongs to the tgf-β superfamily of growth factors, activates a set of downstream genes to subdivide the dorsal region into amnioserosa and dorsal epidermis. here, we examined the expression pattern and transcriptional regulation of dtg, a new target gene of dpp signaling pathway that is required for proper amnioserosa differentiation. we showed that the expression of dtg was controlled by dpp and characterized a 524-bp e ... | 2014 | 24321690 |
| tissue- and stage-dependent dosage compensation on the neo-x chromosome in drosophila pseudoobscura. | sex chromosome dosage compensation (dc) is widely accepted in various organisms. this concept is mostly supported by comparisons of gene expression between chromosomes and between sexes. however, genes on the x chromosome and autosomes are mostly not homologous, and the average gene expression level on these chromosomes may not be the same even under dc, which complicates comparisons between chromosomes. many genes with sex-biased expression also make comparisons between sexes difficult. to over ... | 2014 | 24307686 |
| multifaceted, cross-generational costs of hybridization in sibling drosophila species. | maladaptive hybridization, as determined by the pattern and intensity of selection against hybrid individuals, is an important factor contributing to the evolution of prezygotic reproductive isolation. to identify the consequences of hybridization between drosophila pseudoobscura and d. persimilis, we estimated multiple fitness components for f1 hybrids and backcross progeny and used these to compare the relative fitness of parental species and their hybrids across two generations. we document m ... | 2013 | 24265807 |
| population genetics in the american tropics : 18. the genetic structure of peripheral drosophila pseudoobscura from colombia. | there are several colombian populations of drosophila pseudoobscura which have begun to show divergence. the temporal samples of torobarroso, one of the local populations identified, demonstrate genetic "resourcefulness" and selective opportunism by fluctuating mortality. the data suggest that both balanced selection and mutational origin are necessary to account for the frequencies of drastic genes encountered. in genetic isolates there seems to exist alternatively a mutational component and a ... | 1983 | 24263539 |
| integrated and independent evolution of heteromorphic sperm types. | sperm are a simple cell type with few components, yet they exhibit tremendous between-species morphological variation in those components thought to reflect selection in different fertilization environments. however, within a species, sperm components are expected to be selected to be functionally integrated for optimal fertilization of eggs. here, we take advantage of within-species variation in sperm form and function to test whether sperm components are functionally and genetically integrated ... | 2013 | 24004938 |
| how hot are drosophila hotspots? examining recombination rate variation and associations with nucleotide diversity, divergence, and maternal age in drosophila pseudoobscura. | fine scale meiotic recombination maps have uncovered a large amount of variation in crossover rate across the genomes of many species, and such variation in mammalian and yeast genomes is concentrated to <5kb regions of highly elevated recombination rates (10-100x the background rate) called "hotspots." drosophila exhibit substantial recombination rate heterogeneity across their genome, but evidence for these highly-localized hotspots is lacking. we assayed recombination across a 40kb region of ... | 2013 | 23967224 |
| molecular population genetics of inversion breakpoint regions in drosophila pseudoobscura. | paracentric inversions in populations can have a profound effect on the pattern and organization of nucleotide variability along a chromosome. regions near inversion breakpoints are expected to have greater levels of differentiation because of reduced genetic exchange between different gene arrangements whereas central regions in the inverted segments are predicted to have lower levels of nucleotide differentiation due to greater levels of genetic flux among different karyotypes. we used the inv ... | 2013 | 23665879 |
| mind the gap: upgrading genomes with pacific biosciences rs long-read sequencing technology. | many genomes have been sequenced to high-quality draft status using sanger capillary electrophoresis and/or newer short-read sequence data and whole genome assembly techniques. however, even the best draft genomes contain gaps and other imperfections due to limitations in the input data and the techniques used to build draft assemblies. sequencing biases, repetitive genomic features, genomic polymorphism, and other complicating factors all come together to make some regions difficult or impossib ... | 2012 | 23185243 |
| effects of premature termination codon polymorphisms in the drosophila pseudoobscura subclade. | premature termination codon (ptc) mutations can have dramatic effects--both adaptive and deleterious--on gene expression and function. here, we examine the number and selective effects of ptc mutations within the drosophila pseudoobscura subclade using 18 resequenced genomes aligned to the reference genome. we located and characterized 1,679 ptc mutations in 605 genes across each of these genomes relative to the d. pseudoobscura reference genome, and use rt-pcr to confirm transcription of a subs ... | 2012 | 23132097 |
| experience of mating rivals causes males to modulate sperm transfer in the fly drosophila pseudoobscura. | male responses to risk of sperm competition play an important role in sexual selection, sexual conflict, and the evolution of mating systems. such responses can combine behavioural and physiological processes, and can be mediated through different components of the ejaculate such as sperm numbers and seminal proteins. an additional level of ejaculate complexity is sperm heteromorphism, with the inclusion of non-fertilising parasperm in the ejaculate. we now test the response to rivals in a sperm ... | 2012 | 23085556 |
| evaluation of different reference based annotation strategies using rna-seq - a case study in drososphila pseudoobscura. | rna-seq is a powerful tool for the annotation of genomes, in particular for the identification of isoforms and utrs. nevertheless, several software tools exist and no standard strategy to obtain a reliable annotation is yet established. we tested different combinations of the most commonly used reference-based alignment tools (tophat, gsnap) in combination with two frequently used reference-based assemblers (cufflinks, scripture) and evaluated the potential of rna-seq to improve the annotation o ... | 2012 | 23056304 |
| zinc finger binding motifs do not explain recombination rate variation within or between species of drosophila. | in humans and mice, the cys(2)his(2) zinc finger protein prdm9 binds to a dna sequence motif enriched in hotspots of recombination, possibly modifying nucleosomes, and recruiting recombination machinery to initiate double strand breaks (dsbs). however, since its discovery, some researchers have suggested that the recombinational effect of prdm9 is lineage or species specific. to test for a conserved role of prdm9-like proteins across taxa, we use the drosophila pseudoobscura species group in an ... | 2012 | 23028758 |
| sexual selection and experimental evolution of chemical signals in drosophila pseudoobscura. | our expectations for the evolution of chemical signals in response to sexual selection are uncertain. how are chemical signals elaborated? does sexual selection result in complexity of the composition or in altered quantities of expression? we addressed this in drosophila pseudoobscura by examining male and female cuticular hydrocarbons (chs) after 82 generations of elevated (e) sexual selection or relaxed sexual selection through monogamy (m). the ch profile consisted of 18 different components ... | 2012 | 22984915 |
| time in a bottle: the evolutionary fate of species discrimination in sibling drosophila species. | disadvantageous hybridization favors the evolution of prezygotic isolating behaviors, generating a geographic pattern of interspecific mate discrimination where members of different species drawn from sympatric populations exhibit stronger preference for members of their own species than do individuals drawn from allopatric populations. geographic shifts in species' boundaries can relax local selection against hybridization; under such scenarios the fate of enhanced species preference is unknown ... | 2012 | 22384069 |
| geographic selection in the small heat shock gene complex differentiating populations of drosophila pseudoobscura. | environmental temperature plays a crucial role in determining a species distribution and abundance by affecting individual physiological processes, metabolic activities, and developmental rates. many studies have identified clinal variation in phenotypes associated with response to environmental stresses, but variation in traits associated with climatic adaptation directly attributed to sequence variation within candidate gene regions has been difficult to identify. insect heat shock genes are p ... | 2017 | 22345645 |
| the evolution of multiple mating: costs and benefits of polyandry to females and of polygyny to males. | polyandry is a paradox: why do females mate multiple times when a single ejaculate often provides enough sperm for lifetime egg production? gowaty et al. addressed explanations for polyandry in drosophila pseudoobscura from the perspective of hypotheses based on sex differences in costs of reproduction (cor). contrary to cor, gowaty et al. showed that (1) a single ejaculate was inadequate for lifetime egg production; (2) polyandry provided fitness benefits to females beyond provision of adequate ... | 2017 | 22223093 |
| genomic impacts of chromosomal inversions in parapatric drosophila species. | chromosomal inversions impact genetic variation and facilitate speciation in part by reducing recombination in heterokaryotypes. we generated multiple whole-genome shotgun sequences of the parapatric species pair drosophila pseudoobscura and drosophila persimilis and their sympatric outgroup (drosophila miranda) and compared the average pairwise differences for neutral sites within, just outside and far outside of the three large inversions. divergence between d. pseudoobscura and d. persimilis ... | 2012 | 22201171 |
| hundreds of putatively functional small open reading frames in drosophila. | the relationship between dna sequence and encoded information is still an unsolved puzzle. the number of protein-coding genes in higher eukaryotes identified by genome projects is lower than was expected, while a considerable amount of putatively non-coding transcription has been detected. functional small open reading frames (smorfs) are known to exist in several organisms. however, coding sequence detection methods are biased against detecting such very short open reading frames. thus, a subst ... | 2011 | 22118156 |
| sexual isolation between north american and bogota strains of drosophila pseudoobscura. | sexual isolation, the reduced ability of organisms of different species to successfully mate, is one of the reproductive barriers that prevent gene flow between different taxa. various species-specific signals during courtship are attributed to the sexual isolation between them. drosophila pseudoobscura has been widely used to study the behavioral and genetic mechanisms underlying selection for sexual isolation, as a model system for speciation. d. pseudoobscura and its sibling species, d. persm ... | 2012 | 22065259 |
| a conserved developmental patterning network produces quantitatively different output in multiple species of drosophila. | differences in the level, timing, or location of gene expression can contribute to alternative phenotypes at the molecular and organismal level. understanding the origins of expression differences is complicated by the fact that organismal morphology and gene regulatory networks could potentially vary even between closely related species. to assess the scope of such changes, we used high-resolution imaging methods to measure mrna expression in blastoderm embryos of drosophila yakuba and drosophi ... | 2011 | 22046143 |
| nonrandom gene loss from the drosophila miranda neo-y chromosome. | a lack of recombination leads to the degeneration of an evolving y chromosome. however, it is not known whether gene loss is largely a random process and primarily driven by the order in which mutations occur or whether certain categories of genes are lost less quickly than others; the latter would imply that selection counteracts the degeneration of y chromosomes to some extent. in this study, we investigate the relationship between putative ancestral expression levels of neo-y-linked genes in ... | 2011 | 21987387 |
| genetic architecture of male sterility and segregation distortion in drosophila pseudoobscura bogota-usa hybrids. | understanding the genetic basis of reproductive isolation between recently diverged species is a central problem in evolutionary genetics. here, i present analyses of the genetic architecture underlying hybrid male sterility and segregation distortion between the bogota and usa subspecies of drosophila pseudoobscura. previously, a single gene, overdrive (ovd), was shown to be necessary but not sufficient for both male sterility and segregation distortion in f(1) hybrids between these subspecies, ... | 2011 | 21900263 |
| effects of inversions on within- and between-species recombination and divergence. | chromosomal inversions disrupt recombination in heterozygotes by both reducing crossing-over within inverted regions and increasing it elsewhere in the genome. the reduction of recombination in inverted regions facilitates the maintenance of hybridizing species, as outlined by various models of chromosomal speciation. we present a comprehensive comparison of the effects of inversions on recombination rates and on nucleotide divergence. within an inversion differentiating drosophila pseudoobscura ... | 2011 | 21828374 |
| ancestral polymorphisms in drosophila pseudoobscura and drosophila miranda. | ancestral polymorphisms are defined as variants that arose by mutation prior to the speciation event that generated the species in which they segregate. their presence may complicate the interpretation of molecular data and lead to incorrect phylogenetic inferences. they may also be used to identify regions of the genome that are under balancing selection. it is thus important to take into account the contribution of ancestral polymorphisms to variability within species and divergence between sp ... | 2011 | 21767458 |
| genetics of hybrid male sterility among strains and species in the drosophila pseudoobscura species group. | taxa in the early stages of speciation may bear intraspecific allelic variation at loci conferring barrier traits in hybrids such as hybrid sterility. additionally, hybridization may spread alleles that confer barrier traits to other taxa. historically, few studies examine within- and between-species variation at loci conferring reproductive isolation. here, we test for allelic variation within drosophila persimilis and within the bogota subspecies of d. pseudoobscura at regions previously shown ... | 2011 | 21729052 |
| preference status does not indicate intrinsic quality differences in drosophila pseudoobscura. | the good genes hypothesis states that choosers prefer individuals of high intrinsic quality to individuals of lower intrinsic quality. variation in longevity is thought to reflect, in part, intrinsic quality differences of individuals in addition to the costs of mating and reproduction. here we report longevity variation of drosophila pseudoobscura, a species in which previous experiments have demonstrated that individual mate preferences (pre-touching mate assessments) of females and males are ... | 2010 | 21392338 |