Publications

genic heterogeneity within electrophoretic "alleles" and the pattern of variation among loci in drosophila pseudoobscura.	an investigation, similar to our previously reported xanthine dehydrogenase study, was undertaken to examine the extent of hidden genic variation at nine loci (five larval proteins, three esterases and one aldehyde oxidase) by sequential application of various electrophoretic criteria employing ph, gel concentration and buffer variation. polymorphic loci appear to fall into two distinct groups: weakly polymorphic, including larval protein 6, 7, 8, 10 and 13 and esterase-1 and -6; and highly poly ...	1966	546677
inbreeding and mating patterns in drosophila pseudoobscura.		2004	539969
population genetics of drosophila amylase. ii. geographic patterns in d. pseudoobscura.	morph frequencies of three related polymorphisms were determined in ten natural populations of drosophila pseudoobscura. they are the well-known inversion polymorphism of the third chromosome and the polymorphism for alpha-amylase produced by the structural gene amy (which resides on the third chromosome). the third polymorphism was for tissue-specific expression of amy in adult midguts; a total of 13 different patterns of activity have been observed. the preceding paper (powell and lichtenfels ...	1979	488707
population genetics of drosophila amylase. i. genetic control of tissue-specific expression in d. pseudoobscura.	drosophila pseudoobscura is polymorphic for tissue-specific expression of alpha-amylase in adult midguts. this enzyme is encoded by a single locus, amy, on the third chromosome. in this paper we show: (1) up to about 12 days post-eclosion, the midgut activity patterns remain stable; after 12 days areas not showing activity previously begin to show activity. thus, the genes controlling the expression of amy are temporally acting. (2) diet affects the quantitative, but not the qualitative, express ...	1979	488706
evidence for selection by male mating success in natural populations of drosophila pseudoobscura.	gene arrangement frequencies were determined at two stages in the life history of drosophila pseudoobscura taken from nature. three populations in the central highlands of mexico were each sampled twice during 1976. gene arrangement frequencies were measured in adult males and in larvae that were the offspring of females collected at the same time. the adult males were in all likelihood a representative sample of those who fathered the larvae produced by the wild females. differences in gene arr ...	1979	286338
extent of genetic variation at a highly polymorphic esterase locus in drosophila pseudoobscura.	the esterase-5 locus of drosophila pseudoobscura has been screened for variation by using a wide variety of electrophoretic conditions and by testing heat sensitivity. among 50 isogenic lines from 17 populations, 21 genetic variants were found at the locus, 18 by electrophoresis and 3 by heat denaturation. including alleles previously known, there are a total of 30 alleles at this locus in natural populations. this represents a doubling of the previous estimates of polymorphism at this locus. th ...	1978	283418
frequency-dependent selection at the pgm-1 locus of drosophila pseudoobscura.	frequency-dependent fitness was studied at the pgm-1 locus of drosophila pseudoobscura with respect to two fitness components: rate of development and larva-to-adult survival. the pgm-1 locus is very polymorphic with only two alleles, pgm-1(100) and pgm-1(104), occurring at high frequencies. for each of these two alleles, 20 homozygous strains were obtained from a sample of 1,140 wild-inseminated females. first-instar larvae of the two genotypes were combined in a set of eight different frequenc ...	1979	161241
temperature sensitive events between photoreceptor and circadian clock?	the phase shifting action of low temperature pulses of 6 degrees c and 2 h duration administered to the various phases of the drosophila pseudoobscura circadian rhythm and the action of light pulses given 30 min after the beginning of these low temperature pulses have been investigated. the phase response curve obtained from experiments with light pulses during low temperature cannot be explained on the basis of a straightforward and sequential phase shifting of the oscillation by the various tr ...	2002	125969