The vesicular microstructure is a very distinctive arrangement of calcite, consisting of hollow cavities (vesicles) of diverse sizes and shapes, usually elongated in the direction of shell thickening. It is uniquely found among living bivalves in a single oyster family, Gryphaeidae. The vesicles are distributed in lenses interleaved with compact foliated layers. We have studied the morphology and distribution of vesicles within the lenses using optical and electron microscopy, and micro-computed tomography. At a small scale, vesicles do not follow a classical von Neumann–Mullins route typical of ideal foams. At a larger scale, the initiation and evolution of a vesicular layer statistically proceed like a foam, with vesicles becoming more numerous, larger and more even in size. In summary, the vesicular material follows a foam-like coarsening to reduce the number of energetically costly interfaces. However, a steady state is never reached because the animal permanently introduces energy in the system by creating new vesicles. The fabrication of the vesicular material is mediated by the production of an emulsion between the extrapallial fluid and the precursor PILP of the calcitic walls within the thin extrapallial space. For this mechanism to proceed, the mantle cells must perform highly sophisticated behaviours of contact recognition and secretion. Accordingly, the vesicular material is under mixed physical–biological control.

中文翻译：

---

泡沫牡蛎：通过乳化在灰鲷科中产生囊泡微结构

囊泡微观结构是方解石的一种非常独特的排列，由不同大小和形状的空腔（囊泡）组成，通常在壳增厚的方向上拉长。它在单个牡蛎科 Gryphaeidae 的双壳类动物中是独一无二的。囊泡分布在与紧密叶状层交错的晶状体中。我们使用光学和电子显微镜以及显微计算机断层扫描研究了晶状体内囊泡的形态和分布。在小范围内，囊泡不遵循理想泡沫典型的经典冯诺依曼-穆林斯路线。在更大的范围内，囊泡层的起始和演化在统计上像泡沫一样进行，囊泡变得越来越多、越来越大、大小也越来越均匀。总之，泡状材料遵循泡沫状粗化，以减少能量消耗大的界面的数量。然而，永远不会达到稳定状态，因为动物通过产生新的囊泡永久地在系统中引入能量。囊泡材料的制造是通过在外层流体和薄外层空间内方解石壁的前体 PILP 之间产生乳液来介导的。为了使这种机制继续进行，地幔细胞必须执行高度复杂的接触识别和分泌行为。因此，囊泡材料处于混合物理-生物控制之下。囊泡材料的制造是通过在外层流体和薄外层空间内方解石壁的前体 PILP 之间产生乳液来介导的。为了使这种机制继续进行，地幔细胞必须执行高度复杂的接触识别和分泌行为。因此，囊泡材料处于混合物理-生物控制之下。囊泡材料的制造是通过在外层流体和薄外层空间内方解石壁的前体 PILP 之间产生乳液来介导的。为了使这种机制继续进行，地幔细胞必须执行高度复杂的接触识别和分泌行为。因此，囊泡材料处于混合物理-生物控制之下。