Null models in sexual selection

For next week's labmeeting I suggest to read the paper by Richard Prum in the most recent issue of Evolution about making the Lande-Kirkpatric model of sexual selection the null model, kind of like a Hardy-Weinberg equilibrium. The abstract is posted below. I saw Richard Prum give a presentation at the ISBE this last month, and I really liked his talk. He does not propose any new models for sexual selection, but rather gives ideas for a new perspective on the existing models & the data. Good food for thought, right?

And, to liven up the blog a bit here are some pictures of odonates from my recent trip to Borneo. Enjoy! (both the paper and the pictures).

Abstract:

The Lande-Kirkpatrick mechanism is the null model of evolution by intersexual selection: implications for meaning, honesty, and design in intersexual signals.

The Fisher-inspired, arbitrary intersexual selection models of Lande (1981) and Kirkpatrick (1982), including both stable and unstable equilibrium conditions, provide the appropriate null model for the evolution of traits and preferences by intersexual selection. Like the Hardy–Weinberg equilibrium, the Lande–Kirkpatrick (LK) mechanism arises as an intrinsic consequence of genetic variation in trait and preference in the absence of other evolutionary forces. The LK mechanism is equivalent to other intersexual selection mechanisms in the absence of additional selection on preference and with additional trait-viability and preference-viability correlations equal to zero. The LK null model predicts the evolution of arbitrary display traits that are neither honest nor dishonest, indicate nothing other than mating availability, and lack any meaning or design other than their potential to correspond to mating preferences. The current standard for demonstrating an arbitrary trait is impossible to meet because it requires proof of the null hypothesis. The LK null model makes distinct predictions about the evolvability of traits and preferences. Examples of recent intersexual selection research document the confirmationist pitfalls of lacking a null model. Incorporation of the LK null into intersexual selection will contribute to serious examination of the extent to which natural selection on preferences shapes signals.