Fluctuating asymmetry (subtle departures from identical expression of a trait across an axis
of symmetry) in many taxa is under stabilizing selection for reduced asymmetry. However,
lack of reliable estimates of genetic parameters for asymmetry variation hampers our ability
to predict the evolutionary outcome of this selection. Here we report on a study, based on
analysis of variation within and between isofemale lines and of generation means (line‐
cross analysis), designed to dissect in detail the quantitative genetics of positional …

The genetic basis of fluctuating asymmetry (FA), a measure of random deviations from
perfect bilateral symmetry, has been the subject of much recent work. In this paper we
compare two perspectives on the quantitative genetic analysis of FA and directional
asymmetry (DA). We call these two approaches the character‐state model and the
environmental responsiveness model. In the former approach, the right and left sides are
viewed as separate traits whose genetic coupling is manifested by the genetic correlation …