Geoffrey Miller in the The Mating Mind makes much of the fact that the offspring of any two given parents will display variance because they might possess different combinations of alleles on any given locus. Miller explains that this offers sexual selection an opportunity to weed out deleterious alleles from a population, helping to balance the inevitable generation of new mutations.1
With this in mind, I offer this week’s “You Sexy Thing” from TV Guide pitting Jessica Simpson against her sister Ashlee:
Currently Jessica is winning the vote 90% to Ashlee’s 10%. (Though I can’t help but think they picked out pictures to highlight the difference between the two sisters)
Related: Jessica Simpson and Ashlee Simpson websites….
1 – Reductio ad absurdum if you have two parents who have a lethal recessive on the same locus, the offspring have a 25% chance of expressing the recessive and so decreasing the frequency of the allele in the next generation. Miller imagines that sexual selection might work in a more modest fashion by weighing the die in favor of offspring who receive a greater fraction of “good” alleles.
TangoMan Adds: In comments, Laura adds that plastic surgery introduces a significant variable into the equation. Consider the children that would result from this pairing:
James and Kacie were two strangers brought together by their shared fortune of being selected for “Extreme Makeover.” They became the first two candidates on the show to meet and fall in love! Both shared a similar history of painful memories and disparagement for their appearances.
Here is how the world will see James and Kacie, the parents of their yet unborn children.
And here is the raw genetic material that will be used to conceive their children.
Posted by razib at 09:12 PM