Effect of environmental variation on sexual selection in Drosophila melanogaster

Environmental variations can cause behavioral, physiological and structural changes in different populations of a species which can lead to change in mate preferences. Thus environmental variation can speed the reproductive isolation process by affecting mate choice preference. In the current study, we tried to examine mate choice preference in fruit flies when we change environmental and nutrition conditions during 5 generations. Specimens were split into experiment and control groups, then kept in 50 × 50 × 50 cm compartments under controlled temperature, humidity and light conditions. In each compartment, 12 containers containing 20 fruit flies were placed. Samples were allowed to reproduce for 2 generation under controlled conditions and the third generation of the samples was used for the experiment. In the experimental group, food was gradually changed in each generation. To prevent the inter-breeding of fruit flies in each compartment, after puberty of fruit flies, the flies in each container mixedtogether and then returned to the containers. Accordingly, fruit flies which consumed a variety of food over the five generations prefer to mate with fruit flies feeding similar food. It can be concluded that changes in environmental conditions, such as changes in diet over many generations, can be a prelude to changes in mating behaviors and mate choice preferences. which in the long term can lead to reproductive isolation.

Keywords:

Reproductive isolation , Sexual selection , Environmental variables , Drosophila melanogaster , Reproductive system