Université de Fribourg

Juvenile hormone as a regulator of the trade-off between reproduction and life span in Drosophila melanogaster

Flatt, Thomas ; Kawecki, Tadeusz J.

In: Evolution, 2007, vol. 61, no. 8, p. 1980–1991

Trade-offs between reproduction and life span are ubiquitous, but little is known about their underlying mechanisms. Here we combine treatment with the juvenile hormone analog (JHa) methoprene and experimental evolution in Drosophila melanogaster to study the potential role of juvenile hormone (JH) in mediating such trade-offs at both the physiological and evolutionary level. Exposure to...

Université de Fribourg

Genetically idiosyncratic responses of Drosophila melanogaster populations to selection for improved learning ability

Kawecki, Tadeusz J. ; Mery, Frederic

In: Journal of Evolutionary Biology, 2006, vol. 19, no. 4, p. 1265-1274

To what extent is adaptive evolution over short timescales repeatable? To address this question, we studied the performance of crosses between replicate Drosophila melanogaster lines previously subject to selection for improved learning response in the context of oviposition substrate choice. Of the 10 pairwise F1 crosses among the five selection lines, four performed in the original learning...

Université de Fribourg

Reduced learning ability as a consequence of evolutionary adaptation to nutritional stress in Drosophila melanogaster

Kolss, Munjong ; Kawecki, Tadeusz J.

In: Ecological Entomology, 2008///doi:10.1111/j.1365-2311.2008.01007.x

Abstract. 1. Dietary conditions affect cognitive abilities of many species, but it is unclear to what extent this physiological effect translates into an evolutionary relationship.2. A reduction of competitive ability under nutritional stress has been reported as a correlated response to selection for learning ability in Drosophila melanogaster. Here we test whether the reverse holds as well,...

Université de Fribourg

Life history consequences of adaptation to larval nutritional stress in Drosophila

Kolss, Munjong ; Vijendravarma, Roshan K. ; Schwaller, Geraldine ; Kawecki, Tadeusz J.

In: Evolution, 2009///doi: 10.1111/j.1558-5646.2009.00718.x

Many animal species face periods of chronic nutritional stress where the individuals must continue to develop, grow and/or reproduce despite low quantity or quality of food. Here we use experimental evolution to study adaptation to such chronic nutritional stress in six replicate Drosophila melanogaster populations selected for the ability to survive and develop within a limited time on a very...

Université de Fribourg

Evolutionary biology of starvation resistance: what we have learned from Drosophila

Rion, Stéphanie ; Kawecki, Tadeusz J.

In: Journal of Evolutionary Biology, 2007, vol. 20, no. 5, p. 1655-1664

Most animals face periods of food shortage and are thus expected to evolve adaptations enhancing starvation resistance (SR). Most of our knowledge of the genetic and physiological bases of those adaptations, their evolutionary correlates and trade-offs, and patterns of within- and among-population variation, comes from studies on Drosophila. In this review, we attempt to synthesize the...