Pavlicev and Wagner have a new paper in TREE where they “discuss evidence for variation in pleiotropy and propose the selection, pleiotropy and compensation model (SPC) for adaptive evolution. [This model] predicts that adaptive change in one character is associated with deleterious pleiotropy in others and subsequent selection to compensate for these pleiotropic effects.”¬† They talk about the implications of this model for the genetic basis of evolutionary change and many other things including sexual dimorphism¬† Take a look – this is well worth reading.