Fig. 9. A in Virtual 3D modeling of the ammonoid conch to study its hydrostatic properties

Fig. 9. A. Comparison of the model geometry for Maorites seymourianus defined by the Equation 3, and the closest logarithmic spiral (dotted line) found for these data (radius r = 88.97e-0.12Θ, determination coefficient R2 = 0.988). B. Close up of the initial whorls showing the slow increase in growth rate at the beginning of the ontogeny. The arrows indicate the differences in growth between the polynomial curve (solid arrows) and the logarithmic curve (dashed arrows).