preferential mating

Greenspoon PB & Otto SP 2009 Evolution by Fisherian sexual selection in diploids. Evolution 63:1076-1083.

• the female preference must reach a threshold frequency, perhaps through genetic drift, before a runaway can occur when the rare male trait is disadvantageous
• this presents a challenge to the effectiveness of the fixed-relative preference scheme in generating conditions for runaway sexual selection, restricting runaway selection to cases in which the initial exaggeration of the male trait is favored by natural selection
• Takahasi's point is generally true in the diploid model, except when the fitness of T₁T₂ heterozygotes approaches the fitness of T₁T₁ homozygotes