Dataset S4 from Microstructural biomechanics underpin Cambrian phosphatic brachiopod diversification

Sensitivity analysis of the biomechanical model. Estimated muscle forces were recalculated across a biologically plausible range of specific tension values (10–40 N cm⁻²) and under modified fibre-orientation assumptions affecting effective PCSA. Although absolute force outputs scale predictably with parameter variation, the hierarchical ranking of muscle groups and the relative interspecific differences are preserved. This indicates that the functional interpretation of contrasting biomechanical regimes is not dependent on a single parameter choice.