The relative growth of walking legs of adult Chinese mitten crabs, Eriocheir sinensis in the Odra estuary (Poland). The major axis statistical modeling

We have quantified the relative growth of the merus and the propodus & carpus of walking legs of an adult of Eriocheir sinensis against the carapace width by fitting the major axis lines. Different lines have been fitted to data relative to male and female individuals. Slope and elevation tests have been performed to investigate sexual dimorphism. Isometry tests have been used to classify the relative growth of each part of the legs against the carapace width as isometric or allometric.

All the slope tests have not rejected the null hypothesis of a common slope for the major axes fitted to male data and to female data. However, all the elevation tests have rejected the null hypothesis of a common elevation; so sexual dimorphism was detected for all measured leg parts. The isometry tests have rejected the null hypothesis of isometry only for the merus of the first (left and right) legs of male individuals. All the other isometry tests have not rejected the null hypothesis of isometry. So the relative growth of all the measured leg parts, but the merus of the first (left and right) legs of males, against the carapace width was isometric both for males and for females.