Figure 1.

Boxplots showing the response of morphological traits to manipulation of larval density. Larvae were kept at low or high density (20 vs. 200 larvae per vial). Each experiment was replicated in 2 independent blocks. Morphological traits measured (in millimeters) were (a) body size (L3 wing vein length), (b) testis perimeter, and (c) AG perimeter. The data for testis and AG size are absolute values uncorrected for body size. White bars indicate low larval competition environments (20 larvae per vial); gray bars high larval competition environments (200 larvae per vial).