Publications

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
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
postmating isolation analysis in founder-flush experimental populations of drosophila pseudoobscura.		1996	28568951
temporal stability of third-chromosome inversion frequencies in drosophila persimilis and d. pseudoobscura.		1992	28568997
"sex-ratio" trait, sex composition, and relative abundance in drosophila pseudoobscura.		1982	28581105
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
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
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