Fig. 2. Effect of prior exposure of sperm to unfertilised or recently (1–10 min post exposure) fertilised eggs on (A) sperm concentration and (B) subsequent fertilisation success in Galeolaria caespitosa. All values are means ± s.e.m.; open bars indicate the control (C), lightly shaded bars indicate exposure to recently fertilised eggs (1 and 10 min post fertilisation in A and 10 min post-fertilisation only in B), and black bars indicate exposure to unfertilised eggs (U).