Local adaptation for body color in Drosophila americana

The Role of chromosomal rearrangements in adaptation in Drosophila americana

Natural environments expose organisms to multifarious selective pressures involving numerous aspects of the overall phenotype, therefore eliciting a response from multiple correlated loci. It has been hypothesized that chromosomal rearrangements play a role facilitating local adaptation by establishing new linkage relationships and modifying the recombination patterns between the different chro...

The ontogeny of color: developmental origins of divergent pigmentation in Drosophila americana and D. novamexicana.

Pigmentation is a model trait for evolutionary and developmental analysis that is particularly amenable to molecular investigation in the genus Drosophila. To better understand how this phenotype evolves, we examined divergent pigmentation and gene expression over developmental time in the dark-bodied D. americana and its light-bodied sister species D. novamexicana. Prior genetic analysis impli...

Selection on Codon Usage in Drosophila americana

Synonymous codons are not used at random, significantly influencing the base composition of the genome. The selection-mutation-drift model proposes that this bias reflects natural selection in favor of a subset of preferred codons. Previous estimates in Drosophila of the intensity of selective forces involved seem too large to be reconciled with theoretical predictions of the level of codon bia...

Triploid Intersexuality in Drosophila Americana Spencer.

Local adaptation in Drosophila melanogaster— Molecular and morphological aspects

Drosophila melanogaster is a cosmopolitan species that colonizes a great variety of environments. One trait that shows abundant evidence for naturally segregating genetic variance in different populations of D. melanogaster is cold tolerance. Previous work has found quantitative trait loci (QTL) exclusively on the second and the third chromosomes. To gain insight into the genetic architecture o...