Effects on fitness components of P-element inserts in Drosophila melanogaster: Analysis of trade-offs

TitleEffects on fitness components of P-element inserts in Drosophila melanogaster: Analysis of trade-offs
Publication TypeJournal Article
Year of Publication1996
AuthorsStearns, SC, and Kaiser M
JournalEvolutionEvolution
Volume50
Pagination795-806
Accession NumberA1996UJ15600029
Abstract

We analyzed the trade-offs between fitness components detected in four experiments in which traits were manipulated by inserting small (control) and large (treatment) P-elements into the Drosophila melanogaster genome. Treatment effects and the interactions of treatment with temperature, experiment, and line were caused by the greater length and different positions of the treatment insert. In inbred flies, the treatment decreased early and total fecundity. Whether it increased the lifespan of mated females depended upon adult density. Analysis of line-by-treatment-by-temperature interactions revealed hidden trade-offs that would have been missed by other methods. They included a significant trade-off between lifespan and early fecundity. At 25 degrees C high early fecundity was associated with decreased reproductive rates and increased mortality rates 10-15 days later and persisting throughout life, but not at 29.5 degrees C. Correlations with Gompertz coefficients suggested that flies that were heavier at eclosion also aged more slowly and that flies that aged more slowly had higher fecundity late in life at 25 degrees C. The results support the view that lifespan trades off with fecundity and that late fecundity trades off with rate of aging in fruitflies. Genetic engineering is an independent method for the analysis of trade-offs that complements selection experiments.

Short TitleEvolution