The effect of transient food stress on female mate preference in the stalk-eyed fly Cyrtodiopsis dalmanni

The effect of transient nutritional stress (sucrose culture medium) on fema le mate preference was investigated in the stalk-eyed fly Cyrtodiopsis dalm anni. Two experimental treatments were run in parallel. In the first, femal e preference was initially tested on corn (standard medium) and subsequentl y on sucrose (novel medium). In the second, female preference was tested in the reverse order: sucrose then corn. Females fed on corn had stronger pre ferences for large-eyespan males than females fed on sucrose. Female age, e xperience or the order of exposure to culture media had no effects on the s trength of preference. An additional experiment demonstrated that the sucro se diet reduced the number of developing and mature eggs. We discuss the ad aptive significance of changes in female preference due to transient nutrit ional stress, and the effect of changes in female preference on the strengt h of sexual selection.