Relationships between sinking velocity and volume (top graphic) or shell length (bottom graphic) for actives recruits of the four species and mussel recruits producing byssus thread. Lines are logarithmic regression curves (Ws = a × ln(Size) + b) with their respective coefficients of determination (R²), the solid lines relate to the size range of the individuals studied for each species and the dashed lines correspond to an extension of the regression outside this range.