Université de Fribourg

Visual learning in individually assayed Drosophila larvae

Gerber, Bertram ; Scherer, Sabine ; Neuser, K. ; Michels, B. ; Hendel, T. ; Stocker, Reinhard F. ; Heisenberg, M.

In: Journal of Experimental Biology, 2004, vol. 207, p. 179-188

An understanding of associative learning is facilitated if it can be analyzed in a simple animal like the fruit fly Drosophila. Here, we introduce the first visual associative learning paradigm for larval Drosophila; this is remarkable as larvae have an order of magnitude fewer neurons than adult flies. Larvae were subjected to either of two reciprocal training regimes: Light+/Dark- or...

Université de Fribourg

The effect of learning on experimental evolution of resource preference in Drosophila melanogaster

Kawecki, Tadeusz J. ; Mery, Frederic

In: Evolution, 2004, vol. 58, p. 757-767

Learning is thought to be adaptive in variable environments, whereas constant, predictable environments are supposed to favor unconditional, genetically fixed responses. A dichotomous view of behavior as either learned or innate ignores a potential evolutionary interaction between the learned and innate components of a behavioral response. We addressed this interaction in the context of...

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

No trade-off between learning ability and parasitoid resistance in Drosophila melanogaster

Kolss, Munjong ; Kraaijeveld, A. R. ; Mery, Frederic ; Kawecki, Tadeusz J.

In: Journal of Evolutionary Biology, 2006, vol. 19, no. 4, p. 1359-1363

Learning ability and immunity to parasites are linked at the physiological level in several insect species. The aim of this work was to investigate the relationship between learning and immunity at an evolutionary level. We tested whether selection for improved learning ability in Drosophila melanogaster led to changes in parasitoid resistance as a correlated response. Similarly, we assayed...

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

Influence of plasticity and learning on evolution under directional selection

Paenke, Ingo ; Sendhoff, Bernhard ; Kawecki, Tadeusz J.

In: American Naturalist, 2007, vol. 170, no. 2, p. E47-E58

Phenotypic plasticity and related processes (learning, developmental noise) have been proposed to both accelerate and slow down genetically based evolutionary change. While both views have been supported by various mathematical models and simulations, no general predictions have been offered as to when these alternative outcomes should occur. Here we propose a general framework to study the...

Université de Fribourg

Nutritional value–Dependent and nutritional value–Independent effects on Drosophila melanogaster larval behavior

Rohwedder, Astrid ; Pfitzenmaier, Johanna E. ; Ramsperger, Noel ; Apostolopoulou, Anthi A. ; Widmann, Annekathrin ; Thum, Andreas S.

In: Chemical Senses, 2012, p. -

Gustatory stimuli allow an organism not only to orient in its environment toward energy-rich food sources to maintain nutrition but also to avoid unpleasant or even poisonous substrates. For both mammals and insects, sugars—perceived as “sweet”—potentially predict nutritional benefit. Interestingly, even Drosophila adult flies are attracted to most high-potency sweeteners preferred by...

Université de Fribourg

mPer1 and mPer2 mutant mice show regular spatial and contextual learning in standardized tests for hippocampus-dependent learning

Zueger, M. ; Urani, A. ; Chourbaji, S. ; Zacher, C. ; Lipp, H. P. ; Albrecht, Urs ; Spanagel, R. ; Wolfer, D. P. ; Gass, P.

In: Journal of Neural Transmission, 2006, vol. 113(3), p. 347 - 356

Learning and memory, like most physiological processes, seem to be under the control of circadian rhythm. The recently cloned mPer1 and mPer2 genes play an important role in the regulation of the circadian rhythm. In this study, we tested mPer1 and mPer2 mutant mice in two different learning and memory paradigms, a water-maze place navigation task and contextual fear...