High predictability observed when comparing measured and predicted body mass using type-II linear regression with a major axis approach. Predictions based on preserved mass (A–D) and femur length (E–H) pooling data from three flightless New Zealand grasshopper species: Brachaspis nivalis (pink circles), Paprides nitidus (green triangles), and Sigaus australis (blue squares). The expected x = y relationship is shown in dashed black line, and the observed is shown in solid grey line. Predictions from standardized major axis regressions (SMA) and linear mixed-effects models (LMM) are shown. Note that in most cases fitting lines overlap.