Figure 1.

The probability of females with large and small combs being chosen by males when their combs were covered and when they were visible. When the combs of females were covered, males showed no preference for either large- or small-combed females. When the hoods were removed, males were significantly more likely to copulate with the female with the largest comb. Treatment (covered or visible), F_1,29=10.97, p=0.003. Probability of large-combed female receiving initial copulations (back-transformed LS mean±s.e. tested versus 0.5): covered treatment, 0.35±0.17, t=0.89, d.f.=8, p=0.40; visible treatment, 0.87±0.09, t=3.92, d.f.=8, p=0.004.