Pearson correlation coefficients between semicircular canal area and mass estimates and skull length for bipedal and quadrupedal dinosaurs.

In all cases except the skull length correlation with the PSC in bipedal dinosaurs, both the head size correlations represent increases in the correlation coefficient above that for the body mass estimates. The increases in correlation coefficient for the quadrupedal taxa are substantially larger than those of the bipedal taxa. With the ASC data, this increase in the quadrupedal correlation includes changing from a non-significant correlation with body mass to a significant correlation with both head size metrics. The PSC-head mass correlation is nearly significant (critical value of 0.754). Between the head size metrics, head mass produces stronger correlations than skull length in the vertical canals except for the quadrupedal PSC correlations (see discussion). In contrast, however, the LSC correlations for both bipedal and quadrupedal groups are stronger with the skull length than head mass, suggesting that skull length is more functionally significant for the LSC than either of the vertical canals. ASC: anterior semicircular canal, PSC: posterior semicircular canal, and LSC: lateral semicircular canal. *- indicates a significant correlation at the p = 0.05 level.