DISCUSSION
In this study, we investigated how the selection response depends on and
shapes the genetic architecture of a multicomponent sex pheromone
signal. Through truncation selection, we gradually increased and
decreased the relative amount of acetates across 10 generations. As we
hypothesized, we found that the acetates responded readily to selection,
diverging three-quarters of a standard deviation away from the control
line in 10 generations in both the high and low lines. However, in
contrast to our hypothesis that selection would also result in indirect
responses in the other traits, we found that the response was limited to
the acetates only. In addition, we found that levels of genetic variance
were constant through time, opposite to the expected erosion of genetic
variance in response to selection. Lastly, in line with our
expectations, the genetic covariance structure changed in a way that
likely facilitated a selection response in the pheromone. We discuss
each of these results further below.