The argonaut constructs its shell via physical self-organization and coordinated cell sensorial activity. (A. Checa et al.)_Dataset.

The shell of the cephalopod Argonauta consists of two layers of fibers that elongate
perpendicular to the shell surfaces. Fibers have a calcitic core sheathed by extremely
thin organic membranes, which form a polygonal network in cross-section. During
growth, fibers with small cross-sectional areas tend to shrink, whereas those with large
sections tend to widen, i.e. they follow the von Neumann-Mullins law. We hypothesize
that fibers evolve as an emulsion between the fluid precursors of both the mineral and
organic phases. In addition, when polygons reach big cross-sectional areas, they
become subdivided by new membranes. To interpret this partitioning process we infer
that the living cells from the mineralizing tissue are able to ‘locate’ and subdivide
particularly large polygons. To do this, living cells must perform contact recognition and
subsequent secretion at sub-micron scale. Accordingly, the fabrication of the argonaut
shell proceeds by physical self-organization together with direct cellular activity

头足类船蛸（Argonauta）的外壳由两层纤维构成，这些纤维垂直于壳表面延伸。纤维以极薄有机膜包裹方解石核心，这些有机膜在横截面上形成多边形网络。在生长过程中，横截面积较小的纤维趋于收缩，而横截面积较大的纤维则趋于变宽，即其演化遵循冯·诺依曼-穆林斯定律（von Neumann-Mullins law）。我们提出假说：纤维的演化过程类似矿物相与有机相的流体前驱体之间形成的乳状液。此外，当多边形结构的横截面积达到较大尺寸时，会被新生成的膜分割。为阐释这一分割过程，我们推测矿化组织中的活细胞能够“定位”并分割尺寸过大的多边形。完成该过程需要活细胞具备亚微米尺度下的接触识别能力，并在此后完成分泌活动。据此，船蛸外壳的形成是物理自组织与直接细胞活动共同作用的结果。