Fig. 1

AOX-expressing males are defective in sperm-competition assays. In the defensive paradigm (upper panels), virgin w ¹¹¹⁸ females (white eyes) were initially crossed individually with transgenic males (red eyes), and then with w ¹¹¹⁸ males (white eyes). In the offensive paradigm (lower panels), the virgin w ¹¹¹⁸ females were first crossed with w ¹¹¹⁸ males, and then with transgenic males (see Methods for details). The transgenic males used were 3Xtub-AOX (tubAOX ³⁵/Y; tubAOX ¹¹²/tubAOX ¹¹²; tubAOX ⁷/tubAOX ⁷) in a, and daGAL4 (X/Y; 2/2; daGAL4/daGAL4) in b. Vials I-IV represent the mean number of white- or red-eyed progeny ± SD (error bars), eclosed after 3 days from the initial crosses (vial I), 3 days of egg-laying during second crosses (vial II), 3 days of oviposition only, subsequent to second crosses (vial III, males discarded), followed by 5 days of further oviposition (vial IV)