Shekhar Shashank, Guo Hanliang, Colin Sean P, Marshall Wallace, Kanso Eva, Costello John H
Departments of Physics, Cell Biology and Biochemistry, Emory University, Atlanta, USA.
Whitman Center, Marine Biological Laboratory, Woods Hole, USA.
Nat Phys. 2025 Apr;21(4):624-631. doi: 10.1038/s41567-025-02787-y. Epub 2025 Mar 31.
Evolution of multicellularity from early unicellular ancestors is one of the most important transitions since the origin of life. Multicellularity is associated with enhanced nutrient uptake, better defense against predation, cell specialization and division of labor. While many single-celled organisms exhibit both solitary and colonial forms, the organizing principles governing the transition and the benefits endowed by the colonial states are less clear. Here, we use the suspension-feeding unicellular protist , in which unlike , colony-formation is ephemeral. We show that hydrodynamic coupling between proximal neighbors results in faster feeding flows that depend on the separation between individuals, such that individuals in a dynamic colony have stronger feeding flows on average. Moreover, accrued feeding benefits are typically asymmetric; individuals with weaker solitary currents gain more from partnering than those with faster currents. Our finding that colonial organization in simple unicellular organisms is beneficial provides fundamental insights into the selective forces favoring the early evolution of multicellular organization.
从早期单细胞祖先进化出多细胞性是生命起源以来最重要的转变之一。多细胞性与增强营养吸收、更好地抵御捕食、细胞特化和分工相关。虽然许多单细胞生物既表现出独居形式也表现出群体形式，但控制这种转变的组织原则以及群体状态所带来的益处尚不清楚。在这里，我们使用悬浮摄食的单细胞原生生物，与不同的是，其群体形成是短暂的。我们表明，近端邻居之间的流体动力耦合导致更快的摄食流，这取决于个体之间的距离，因此动态群体中的个体平均具有更强的摄食流。此外，累积的摄食益处通常是不对称的；独居时水流较弱的个体从合作中获得的益处比水流较快的个体更多。我们发现简单单细胞生物中的群体组织是有益的，这为有利于多细胞组织早期进化的选择力提供了基本见解。
