Fig. 4

Relationships between morphological characteristics (MIs) and proportion of amphipods. Circle size indicates the relative amount of total prey number the fish ate. Blue lines indicate the regression lines predicted in the GLM multiple regression analysis with standard length as a covariate. MIs represent the morphological indices determined by the residuals in linear regressions for mouth length by standard length (MI1), mouth width by standard length (MI2), and mouth width by mouth length (MI3, i.e., mouth narrowness), respectively