A new method to analyze habitat preference and mate choice.

HURTADO J.; SOTO E.M.; CORTESE M.

DROSOPHILA INFORMATION SERVICE

University of Oklahoma

Lugar: Norman, Oklahoma; Año: 2005 vol. 88 p. 134 - 135

0070-7333

Habitat preference and mate choice are key components in models of sympatric speciation.Thus, the close relationship between these complex traits makes their joint study necessary. Suchstudies not only require an experiment for habitat preference and another for mate choice, but also the combined analysis of both. In order to facilitate such analysis and to allow the simultaneous analysis of both traits, we designed a device that allows the choice between two different habitats and to test for mate choice with the same sample of flies. These two habitats may differ in their resources, for example different odors quests.The device consists of three adjacent boxes, each one made of transparent acrylic and divided into two equal size compartments by a mobile barrier. One tube connects each compartment of the lateral boxes with its adjacent compartment of the central box. The latter, in turn, presents pieces of a porous fabric, which allows air circulation defining two different odorous zones (Figure 1). Lateral boxes have holes to which insect aspirators can be attached for fly collecting purposes (Figure 2).A sample of flies is introduced in the central box, males in one of the compartment and females in the other, and allowed to choose between two environments by following volatile compounds of different attractants situated in each one of the lateral boxes. This choice simulates habitat preference. Once the flies made their choice, the barriers, dividing the compartments of thelateral boxes, are opened, and then it is possible to test mate choice within each environment and between different strains by aspirating mating couples and subsequent individual identification. As a variant, it can be used a dark and opaque central box in order to increase the dispersal rate and reduce returning rate to the central box. We also recommend this method for jointly testing  habitat preference and mate choice or any interaction between different strains. In addition, the device may be used as a new alternative in artificial selection experiments. For example, it may be useful for testing the correlation between habitat preference and mate choice by comparing the efficiency of artificial selection either for habitat preference or mate choice with artificial selection for both traits at the same time. Acknowledgments: The authors wish to thank Ignacio Soto and Esteban Hasson for criticismson earlier versions of this report. This work was supported by grants of ANPCyT (PICT 11084) and UBA (X299) awarded to Esteban Hasson.