A quantitative genetic study of starvation resistance at different geographic scales in natural populations of Drosophila melanogaster

GOENAGA, J.; FANARA, JJ.; HASSON, E.

GENETICAL RESEARCH

CAMBRIDGE UNIV PRESS

Año: 2010 vol. 92 p. 253 - 259

0016-6723

Food shortage is a stress factor that commonly affects organisms in nature. Resistance to food shortage or starvation resistance is a complex quantitative trait with direct implications on fitness. However, surveys of natural genetic variation in starvation resistance at different geographic scales are scarce. Here we measured variation in starvation resistance in sets of lines derived from nine natural populations of Drosophila melanogaster collected in western Argentina. Our study shows that within population variation explained a larger proportion of overall phenotypic variance (80%) than among populations (7%). We also noticed that an important fraction of variation was sex-specific. Overall females were more resistant to starvation than males; however, the magnitude of the sexual dimorphism in starvation resistance varied among lines and explained a significant fraction of phenotypic variance in all populations. Estimates of cross-sex genetic correlations suggest that the genetic architecture of starvation resistance is only partially shared between sexes in the populations examined, thus, facilitating further evolution of the sexual dimorphism