TY - JOUR
T1 - Abdominal pigmentation variation in Drosophila polymorpha
T2 - Geographic variation in the trait, and underlying phylogeography
AU - Brisson, Jennifer A.
AU - De Toni, Daniela Cristina
AU - Duncan, Ian
AU - Templeton, Alan R.
PY - 2005/5
Y1 - 2005/5
N2 - Drosophila polymorpha is a widespread species that exhibits abdominal pigmentation variation throughout its range. To gain insight into this variation we combined phenotypic and genotypic data to test a series of nested hypotheses. First, we tested the null hypothesis that geographic variation in pigmentation is due to neutral factors. We used nested clade analysis to examine the distribution of haplotypes from a nuclear and a mitochrondrial locus. Restricted gene flow via isolation by distance, the primary inference of this phylogeographic analysis, was then used to generate and test the hypothesis of increasing average abdominal pigmentation difference with increasing geographic distance. We found no correlation between geographic distance and phenotypic distance. We then tested the hypothesis that pigmentation is affected by environmental differences among localities. We found a significant effect of habitat type on the average abdominal pigmentation phenotype of different localities. Finally, we tested the hypothesis that pigmentation in D. polymorpha is associated with desiccation resistance. We found that dark individuals of both sexes survived significantly longer in a desiccating environment than light individuals. These patterns combined lead us to hypothesize that abdominal pigmentation variation in D. polymorpha is important in mediating the organism's interactions with local ecological factors.
AB - Drosophila polymorpha is a widespread species that exhibits abdominal pigmentation variation throughout its range. To gain insight into this variation we combined phenotypic and genotypic data to test a series of nested hypotheses. First, we tested the null hypothesis that geographic variation in pigmentation is due to neutral factors. We used nested clade analysis to examine the distribution of haplotypes from a nuclear and a mitochrondrial locus. Restricted gene flow via isolation by distance, the primary inference of this phylogeographic analysis, was then used to generate and test the hypothesis of increasing average abdominal pigmentation difference with increasing geographic distance. We found no correlation between geographic distance and phenotypic distance. We then tested the hypothesis that pigmentation is affected by environmental differences among localities. We found a significant effect of habitat type on the average abdominal pigmentation phenotype of different localities. Finally, we tested the hypothesis that pigmentation in D. polymorpha is associated with desiccation resistance. We found that dark individuals of both sexes survived significantly longer in a desiccating environment than light individuals. These patterns combined lead us to hypothesize that abdominal pigmentation variation in D. polymorpha is important in mediating the organism's interactions with local ecological factors.
KW - Abdominal pigmentation
KW - Cardini group
KW - Drosophila polymorpha
KW - Phenotypic variation
KW - Phylogeography
UR - http://www.scopus.com/inward/record.url?scp=19544362500&partnerID=8YFLogxK
U2 - 10.1111/j.0014-3820.2005.tb01043.x
DO - 10.1111/j.0014-3820.2005.tb01043.x
M3 - Article
C2 - 16136804
AN - SCOPUS:19544362500
SN - 0014-3820
VL - 59
SP - 1046
EP - 1059
JO - Evolution
JF - Evolution
IS - 5
ER -