As the study notes, women might make different choices if they knew just how costly their preferences turn out to be.
On the other hand, disruptive natural selection favours the evolution of (costly) female preferences, since it creates and maintains variation in genetic quality.
Most sexual selection models are more complex than assortative mating models, but they have the considerable advantage that costly female preferences can evolve from scratch, whereas costly assortative mating cannot easily get off the ground.
The second scenario, in which the treatment for the rare disease was more costly, examined preferences for rarity in the context of a more realistic situation in which the rare disease was more costly to treat.
To measure how strong natural selection against costly female preferences is, I applied the methodology of Barton and Turelli [ 23] to calculate the strength of direct selection of preference.
Models explicitly considering multiple male traits with costly female preference, in terms of search costs/viability selection, also found that female preferences did not evolve due to high joint costs to preference [ 24, 25].
The sexual selection part of the model considers the evolution of a (costly) female preference for a (costly) male ornament.
According to theoretical analyses, however, a pure sexy sons process, in which the only benefit to females of mating with attractive males comes from the increased mating success of sons [ 29, 51], cannot maintain a costly female preference at equilibrium [ 29, 30, 74].
Although there is evidence from various taxa that mate preferences are costly [ 75, 76], it is possible that they have little or no cost in our D. melanogaster laboratory population, where females can readily sample numerous males and rejected unwanted males with little effort.
Instead of fighting the science on climate change, we should champion nuclear power against the Obama administration's preference for costly, subsidised wind and solar power.DIA: Is today's Republican Party too beholden to social conservatives?Mr Frum: Today's Republican party is too beholden to factions generally.
