Direct and correlated responses to selection for longevity in Drosophila buzzatii

ALEJANDRA C. SCANNAPIECO; PABLO SAMBUCETTI; FABIAN M. NORRY

BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY

Wiley - Blackwell

Año: 2009 p. 738 - 748

0024-4066

The possible associations between longevity, early fecundity, and stress-resistance traits were explored usingartificial selection on longevity in a laboratory population of Drosophila buzzatii. Three replicated lines wereselected for increased lifespan (L lines) and compared with the respective unselected controls (C lines) after the14th generation of selection. Mean longevity exhibited a significant response to selection. The baseline mortalitytended to decrease in the L lines and a negative correlated response to longevity selection was found for earlyfecundity. Egg-to-adult developmental time increased in L lines. Longevity selection increased stress resistance forboth high and low temperatures, as measured by heat knockdown resistance and chill-coma recovery. Starvationresistance also tended to be higher in L than in C lines. The results obtained are consistent with the hypothesisof trade-offs between longevity and early fecundity, and also suggest a trade-off association between adult longevityand developmental time. Correlated selection responses were generally consistent with correlations among thetraits previously inferred from altitudinal clines for longevity and stress-resistance phenotypes. © 2009 TheLinnean Society of London, Biological Journal of the Linnean Society, 2009, 97, 738–748.ADDITIONAL KEYWORDS: longevity selection – chill-coma recovery – cline – early fecundity – heatknockdown resistance – senescence – starvation – trade-off.