Fig. 3

The SAD algorithm for the shortest anticlinal division (a) and temporal sequence showing its application (b) to generate growth and exemplary divisions of the apical initial and its nearest derivatives. In a, among many possibilities of anticlinal divisions (green), the wall with the smallest division plane (yellow) was selected. This plane, defined by a and t ₁ is perpendiculat to t ₂ . In b the initial (circle) renews itself and maintains contact with the dome summit (arrowhead), whereas all of the derivatives are displaced basipetally further away from the summit during growth. All of the cells divide perpendicularly to the surface along the shortest division plane but with different the orientation with respect to meridional growth trajectories (green). The walls 1 and 2 result from more or less the meridional and latitudinal divisions, respectively, whereas the remaining walls result from the oblique ones