In our discussion of Weis and Abrahamson’s work on goldenrod galls (data plotted in Figure...

In our discussion of Weis and Abrahamson’s work on goldenrod galls (data plotted in Figure), we mentioned that the researchers established that there is heritable variation among flies in the size of the galls they induce. How do you think Weis and Abrahamson did this? Describe the necessary experiment in as much detail as possible.

Figure Stabilizing selection on a gall-making fly (a) Parasitoid wasps kill fly larvaein small galls at higher rates than larvae in large galls (left). Birds kill larvae in large galls at higher ratesthan they kill larvae in small galls (right). (b) The distribution of gall sizes before (tan + red portion of bars) and after (red portion) selection by parasitoids and birds. Overall, fly larvae in medium galls survived at the highest rates. From Weis and Abrahamson (1986).