| the relationship between the intensity of light phases and the extent of phase shifts of the circadian rhythm in the eclosion rate of drosophila pseudoobscura. | | 1969 | 5372004 |
| morphological differences between drosophila pseudoobscura populations selected for opposite geotaxes and phototaxes. | | 1969 | 17248462 |
| the genetic basis of sound production in drosophila pseudoobscura and d. persimilis. | | 1969 | 5370966 |
| factors determining rates of the evolution of fitness in laboratory populations of drosophila pseudoobscura. | | 1969 | 17248453 |
| on the absence of circadian rhythmicity in drosophila pseudoobscura pupae. | | 1969 | 5798455 |
| the genetics of drosophila mating behavior. ii. the genetic architecture of mating speed in drosophila pseudoobscura. | | 1969 | 5371028 |
| chromosomal polymorphism and genetic load in drosophila pseudoobscura. | | 1969 | 5364967 |
| a molecular approach to the study of genic heterozygosity in natural populations. iv. patterns of genic variation in central, marginal and isolated populations of drosophila pseudoobscura. | | 1969 | 5364966 |
| action spectra for phase shifts of a circadian rhythm in drosophila. | action spectra were determined for lightinduced phase shifts of the circadian rhythm of adult emergence in drosophila pseudoobscura. the action spectra for advance and delay phase shifts are similar; the most effective wavelengths are in the blue region, with a sharp cutoff above 500 nanometers. this similarity suggests that the same photoreceptive pigment mediates both advance and delay phase shifts. | 1969 | 5762935 |
| direct evidence of genic differentiation between sex ratio and standard gene arrangements of x chromosome in drosophila pseudoobscura. | evidence of strong association of alleles at the esterase-5 and adult acid phosphatase-6 loci with the sex ratio and the standard x chromosome arrangements in d. pseudoobscura is presented. there is no differentiation at these two loci, either in the sex ratio or the standard arrangement from two widely separated geographic populations. at the esterase-5 locus, alleles characteristic of one arrangement are found in low frequencies in the other arrangement. it is concluded, from these and other o ... | 1972 | 5073855 |
| developmental studies in drosophila. vi. ultrastructural analysis of the salivary glands of drosophila pseudoobscura during the late larval period. | | 1972 | 4340674 |
| genetic analysis of geotactic and phototactic behavior in selected strains of drosophila pseudoobscura. | | 1972 | 4664205 |
| fitness of allozyme variants in drosophila pseudoobscura. i. selection at the pgm-1 and me-2 loci. | we have studied in drosophila pseudoobscura the effect of allozyme variation on seven fitness components: female fecundity, egg hatchability, egg-to-adult survival under near-optimal and under competitive conditions, rate of development under near-optimal and under competitive conditions, and mating capacity of males. three genotypes at each of two loci, pgm-1 and me-2, have been studied in various combinations. these two loci are highly polymorphic in natural populations of d. pseudoobscura. st ... | 1975 | 1126623 |
| further evidence for selective differences between isoalleles in drosophila. | a number of separate strains of drosophila pseudoobscura were inbred for 38 generations of brother-sister mating with forced heterozygosity for two alleles of either the octanol dehydrogenase or esterase-5 locus. crosses were set up within each of these inbred lines such that simple mendelian ratios were expected, and eggs from these crosses were placed on media with additions simple chemicals likely to interact with alleles of the two loci--octanol and ethanol for the odh locus and tributyrin a ... | 1975 | 1126619 |
| fitness of karyotypes in drosophila pseudoobscura. | in the dynamics of the survival of chromosomal polymorphism selection may be operating at the genic level, at the chromosomal level or at the supergene level. tests designed to distinguish between these levels were run on drosophila pseudoobscura. there was no evidence for heterosis, a necessary requirement for gene-determined chromosomal polymorphism a strong chromosmal selection was observed. no evidence was found for the presence within one locality of more than a single superallele for each ... | 1975 | 1126618 |
| dosage compensation of genes on the left and right arms of the x chromosome of drosophila pseudoobscura and drosophila willistoni. | we have investigated the occurrence of dosage compensation in d. willistoni and d. pseudoobscura, two species whose x chromosome is metacentric with one arm homologous to the x and the other homologous to the left arm of chromosome 3 of d. melanogaster. crude extracts were assayed for isocitrate dehydrogenase (xr), glucose-6-phosphate dehydrogenase (xl?), 6-phosphogluconate dehydrogenase (xl?), and alpha-glycerophosphate dehydrogenase (chromosome 2) in d. willistoni, and for esterase-5 (xr), glu ... | 1974 | 4455556 |
| genetic background and the fitness of allozymes. | experimental perturbations of gene frequency at the esterase-5 locus in drosophila pseudoobscura were carried out in a series of population cages started with differing numbers of founder chromosomes. cages founded with few chromosomes showed changes in gene frequency at the allozyme locus. such changes were less marked in cages founded with a larger sample of chromosomes. these experiments show the importance of linkage disequilibrium in affecting allozyme frequencies, and emphasize the necessi ... | 1974 | 4455555 |
| esterases of drosophila. ii. biochemical studies of esterase-5 in d. pseudoobscura. | in vitro enzyme hybridization was carried out with combinations of six allozymic variants of esterase-5 from drosophila pseudoobscura. studies on heat stability and specific activity changes accompanying hybridization were done to examine the possible expression of overdominance at the biochemical level. in 11 of 15 combinations no significant change in specific activity was found following hybridization. in two cases hybridization resulted in a decrease in activity in the mixture, while in two ... | 1974 | 4455554 |
| rates of dispersal of drosophila pseudoobscura and its relatives. | | 1974 | 4154451 |
| fitness of allozyme variants in drosophila pseudoobscura. ii. selection at the est-5, odh and mdh-2 loci. | | 1974 | 4452479 |
| light dependence in matings of drosophila pseudoobscura. | | 1974 | 4414479 |
| genetic loads affecting fertility in natural populations of drosophila pseudoobscura. | | 1967 | 5586879 |
| genetic loads affecting longevity in natural populations of drosophila pseudoobscura. | | 1967 | 6057227 |
| circadian systems. i. the driving oscillation and its assay in drosophila pseudoobscura. | | 1967 | 5237901 |
| gene arrangements in the third chromosome of drosophila pseudoobscura. ii. all possible configurations. | | 2003 | 6055325 |
| genetic loads affecting fecundity in natural populations of drosophila pseudoobscura. | | 1967 | 6040492 |
| an experiment on migration and simultaneous selection for several traits in drosophila pseudoobscura. | | 1967 | 6036950 |
| variability within and between strains for mating behavior parameters in drosophila pseudoobscura. | | 1967 | 6032107 |
| a new gene arrangement in the third chromosome of drosophila pseudoobscura. | | 2003 | 6031680 |
| mating control by gene arrangements in drosophila pseudoobscura. | | 1966 | 17248341 |
| gene arrangements in the third chromosome of drosophila pseudoobscura. i. configurations with tester chromosomes. | | 2003 | 5971037 |
| purification of esterase-5 from drosophila pseudoobscura. | | 1966 | 5969303 |
| comparison of selection responses on body weight under divergent larval density conditions in drosophila pseudoobscura. | | 1966 | 5968645 |
| a molecular approach to the study of genic heterozygosity in natural populations. ii. amount of variation and degree of heterozygosity in natural populations of drosophila pseudoobscura. | | 1966 | 5968643 |
| gene differences between the sex ratio and standard gene arrangements of the x chromosome and linkage disequilibrium between loci in the standard gene drosophila pseudoobscura. | the standard and sex ratio gene arrangements of the x chromosome of d. pseudobscura differ from each other in allele frequencies at the four x chromosome loci, esterase-5, adult acid phosphatase-6, phosphoglucomutase-1 and octanol dehydrogenase-3. the standard arrangement which is the common arrangement in all populations is polymorphic at these loci in varying degrees, the geographically less widespread sex ratio arrangement has little polymorphism and is genically predominantly e-5(1.04) ap-6( ... | 1974 | 4417060 |
| selection by fertility in drosophila pseudoobscura. | fertility, the component of selection due to female fecundity and male mating success, differed significantly among the st/st, st/ar, and ar/ar karyotypes in experimental populations and varied with karyotypic frequency. in relation to st/ar, st/st females and males had higher fertilities at low frequency; ar/ar males and females were at a significant fertility disadvantage at intermediate frequency, while at low and at high frequencies their fertilities matched or exceeded that of the heterokar ... | 1974 | 4426507 |
| age, experience, and rare-male mating advantages in drosophila pseudoobscura. | | 1974 | 4842092 |
| cold temperature resistance, chromosomal polymorphism and interpopulation heterosis in drosophila pseudoobscura. | descendants of two colorado, u.s.a., populations of d. pseudoobscura, boulder and la foret, were exposed to +2 degrees and -2 degrees . in third instar larvae from boulder ar and pp third chromosome gene arrangements survived better than tl and others, while the reverse situation occurred for la foret. deleterious dominant effects were observed for ar from la foret. in adults from boulder there was a trend towards greater survival for ar and pp than for other gene arrangements, while ar from la ... | 1974 | 4838761 |
| on the very rapid enhancement by d2o of the temperature-tolerance of adult drosophila. | deuterium oxide, d(2)o, increases the temperature-tolerance of drosophila pseudoobscura when it is administered to adult flies as a sucrose solution. the effect is very rapidly exerted; it is detected within 10 min after the flies have a brief (10 min) opportunity to drink. this increased resistance to heat-death surely implies an increased resistance of macromolecules to thermal denaturation. d(2)o is known to exert such an effect on in vitro protein solutions. the speed with which the increase ... | 1974 | 4521820 |
| early and late subjective night phases of the drosophila pseudoobscura circadian rhythm require different energies of blue light for phase shifting. | | 2009 | 4273696 |
| studies on the sal locus in drosophila pseudoobscura. 3. the molecular pattern of dna in active and inactive chromosome regions. | | 1973 | 4762789 |
| a differential effect of heavy water on temperature-dependent and temperature-compensated aspects of circadian system of drosophila pseudoobscura. | d(2)o is the only "chemical" agent that consistently affects the frequency of circadian oscillations: its effect is now known to be so widespread and predictable that its action merits closer study as a potential clue to the currently obscure concrete nature of circadian oscillators. the great diversity of d(2)o effects on biological systems in general is briefly reviewed and the need for rejectable hypotheses concerning the action of d(2)o on circadian clocks is stressed because current specula ... | 1973 | 4516204 |
| temporal frequency changes of enzyme and chromosomal polymorphisms in natural populations of drosophila. | a comparative study of chromosomal and enzyme polymorphisms in drosophila pseudoobscura and in d. persimilis was conducted from april 1971 to october 1972 by taking samples at monthly intervals in two different localities. seasonal cyclic changes occur in the chromosomal polymorphisms. significant changes occur in the frequencies of the enzyme polymorphisms; preliminary evidence indicates that some of these changes may also be cyclic. natural selection is the main process responsible for the cha ... | 1973 | 4514981 |
| chromosomal control of mating activity in drosophila pseudoobscura. | lines containing two third-chromosome inversions (arrowhead and pikes peak) of drosophila pseudoobscura selected for fast and slow mating speed were crossed to a multichromosomal, dominant marker inversion stock, and strains with various combinations of chromosomal derivation were tested for their mating activity. when lines were selected isodirectionally with the known third-chromosome control, the third chromosome was found to possess major epistatic control over mating speed, followed by the ... | 1973 | 4510290 |
| viabilities of third chromosomes of drosophila pseudoobscura differing in relative competitive fitness. | arrowhead (ar) third chromosome arrangements of drosophila pseudoobscura, whose competitive fitnesses had been determined in population cages, were tested for their genetic loads in homozygous, heterozygous (homokaryotypic), and heterokaryotypic (ar/ch) combinations. the results showed that their competitive population cage performances were correlated to their viabilities as homozygotes but were not correlated to their viabilities as heterozygotes or as heterokaryotypes. however, the results do ... | 1972 | 4652876 |
| bichromosomal synthetic semilethals in drosophila pseudoobscura. | | 1965 | 14338225 |
| genetic divergence in m. vetukhiv's experimental populations of drosophila pseudoobscura. 2. longevity. | | 1965 | 14297592 |
| genetic loads in irradiated experimental populations of drosophila pseudoobscura. | | 1964 | 14239789 |
| lethal and semilethal chromosomes in irradiated experimental populations of drosophila pseudoobscura. | | 1964 | 14239788 |
| inbreeding and viability in experimental populations of drosophila pseudoobscura. | | 1964 | 14231442 |
| the capacity for increase in chromosomally polymorphic and monomorphic populations of drosophila pseudoobscura. | | 1964 | 14221018 |
| mating speed control by gene arrangements in drosophila pseudoobscura homokaryotypes. | | 1964 | 14215621 |
| genetic differentiation within laboratory populations of drosophila pseudoobscura. | | 1964 | 5849558 |
| genetics of natural populations. xxxiv. adaptive norm, genetic load and genetic elite in drosophila pseudoobscura. | | 1963 | 14083044 |
| comparative fitness of experimental populations of drosophila pseudoobscura. | | 1963 | 14080688 |
| genetic studies of natural populations of drosophila: drosophila pseudoobscura, a large dominant population. | | 1963 | 13984396 |
| sex-linked inheritance of a quantitative trait of drosophila pseudoobscura. | | 1963 | 17248170 |
| genetic potential for an extra crossvein in drosophila pseudoobscura. | | 1963 | 17248168 |
| genetics of natural populations. 32. inbreeding and the mutational and balanced genetic loads in natural populations of drosophila pseudoobscura. | | 1963 | 14028273 |
| a comparison of purebred and crossbred selection schemes with two populations of drosophila pseudoobscura. | | 1963 | 17248144 |
| effects of temperature and x-ray irradiation on intrinsic growth rate in populations of drosophila pseudoobscura. | | 1963 | 14058260 |
| genetics of natural populations. xxxi. genetics of an isolated marginal population of drosophila pseudoobscura. | | 1963 | 14028271 |
| selection for geotaxis in monomorphic and polymorphic populations of drosophila pseudoobscura. | | 1962 | 16591004 |
| selection and body size in drosophila pseudoobscura at different temperatures. | | 1962 | 13887953 |
| genetic drift and natural selection in experimental populations of drosophila pseudoobscura. | | 1962 | 13886810 |
| studies on the sal locus in drosophila pseudoobscura. ii. modes of regulation of the sal banding pattern. | from a consideration of genetic and chromosomal alterations which affect the banding pattern of a specific salivary chromosome region, it is concluded that (1) a regulator locus, sal, is closely linked with the region in question but separated from it spatially by a few bands; (2) either mutation of the sal locus or transfer of the region to a heterochromatic region affects the banding pattern similarly; and (3) the change probably consists of a compaction of dna and a concomitant inactivation o ... | 1972 | 4643822 |
| artificial and natural selection for two behavioral traits in drosophila pseudoobscura. | in an attempt to elucidate the genetic architecture of two behavioral traits, populations of drosophila pseudoobscura were selected for positive and for negative phototaxis and geotaxis. the selected populations diverged rapidly in their behavior (figs. 1 and 2). the selection was relaxed after 20 generations in the phototactic, and after 30 generations in the geotactic populations. the relaxation resulted in convergence almost as rapid as was the divergence under selection. the average phototac ... | 1969 | 5253666 |
| further evidence for coadaptation in crosses between geographic populations of drosophila pseudoobscura. | | 1968 | 5713603 |
| the genetics of drosophila mating behaviour. i. organization of mating speed in drosophila pseudoobscura. | | 1968 | 5709775 |
| courtship and mating time in drosophila pseudoobscura. | | 1968 | 5709773 |
| genetics of natural populations. xl. heterotic and deleterious effects of recessive lethals in populations of drosophila pseudoobscura. | | 1968 | 5705830 |
| temperature compensation of the circadian oscillation in drosophila pseudoobscura and its entrainment by temperature cycles. | | 1968 | 5655535 |
| selection for higher fitness in populations of drosophila pseudoobscura. | four laboratory populations, each consisting of flies homozygous for a wild second chromosome, were maintained in population cages. three of them were initially characterized by low fecundity of the females; the fourth was a control. after 15 months, in all three populations with low fecundity this character was much improved; two of them, have reached the control level. the changes observed were presumably due to mutation and selection under highly competitive conditions. | 1968 | 5642574 |
| frequency dependence of mating success in drosophila pseudoobscura. | | 1968 | 5647626 |
| parental age effects in drosophila pseudoobscura. | | 1968 | 5697303 |
| genetics of natural populations. xxxix. a test of the possible influence of two insecticides on the chromosomal polymorphism in drosophila pseudoobscura. | | 1968 | 5668291 |
| selection for and against gregariousness in the choice of oviposition sites by drosophila pseudoobscura. | | 1968 | 5664388 |
| genetic divergence in m. vetukhiv's experimental populations of drosophila pseudoobscura. iv. relative viability. | | 1967 | 5587945 |
| rates of spontaneous mutation in the second chromosomes of the sibling species, drosophila pseudoobscura and drosophila persimilis. | | 1954 | 17247527 |
| the genotypic control of crossing over in drosophila pseudoobscura. | | 1954 | 17247512 |
| environmental modification of heterosis in drosophila pseudoobscura. | | 1954 | 16589496 |
| heterosis and the integration of the genotype in geographic populations of drosophila pseudoobscura. | | 1954 | 17247469 |
| viability of hybrids between local populations of drosophila pseudoobscura. | | 1953 | 16589231 |
| experiments on sexual isolation in drosophila: x. reproductive isolation between drosophila pseudoobscura and drosophila persimilis under natural and under laboratory conditions. | | 1951 | 16589029 |
| morphological differences between two sibling species; drosophila pseudoobscura and drosophila persimilis. | | 1951 | 14808171 |
| genetics of natural populations. xix. origin of heterosis through natural selection in populations of drosophila pseudoobscura. | | 1950 | 15414931 |
| genetics of natural populations; experiments on chromosomes of drosophila pseudoobscura from different geographic regions. | | 1948 | 18100290 |
| genetics of natural populations; proof of operation of natural selection in wild populations of drosophila pseudoobscura. | | 1948 | 18100287 |
| studies on sex-ratio in drosophila pseudoobscura; selection and sex-ratio. | | 1948 | 18884662 |
| observations on the mating behavior of drosophila pseudoobscura and d. persimilis. | | 1948 | 18884172 |
| adaptive properties of carriers of certain gene arrangements in drosophila pseudoobscura. | | 1948 | 18863985 |
| the suppression of crossing over in inversion heterozygotes of drosophila pseudoobscura. | | 1948 | 16588794 |
| influence of humidity on the survival of different chromosomal types in drosophila pseudoobscura. | | 1947 | 16588745 |
| genetics of natural populations; rate of diffusion of a mutant gene through a population of drosophila pseudoobscura. | | 1947 | 20244463 |
| genetics of natural populations; a response of certain gene arrangements in the third chromosome of drosophila pseudoobscura to natural selection. | | 1947 | 20292738 |
| effectiveness of intraspecific and interspecific matings in drosophila pseudoobscura and drosophila persimilis. | | 2015 | 20286615 |
| genetics of sexual isolation between drosophila pseudoobscura and drosophila persimilis. | | 1946 | 17247220 |
| experiments on sexual isolation in drosophila: viii. influence of light on the mating behavior of drosophila subobscura, drosophila persimilis and drosophila pseudoobscura. | | 1946 | 16578209 |
| a molecular approach to the study of genic heterozygosity in natural populations. i. the number of alleles at different loci in drosophila pseudoobscura. | | 1966 | 5968642 |
| sexual isolation caused by selection for positive and negative phototaxis and geotaxis in drosophila pseudoobscura. | | 1966 | 5229969 |