Costello John H, Colin Sean P, Gemmell Brad J, Dabiri John O, Sutherland Kelly R
Eugene Bell Center, Marine Biological Laboratory, Woods Hole, Massachusetts 02543, USA.
Department of Biology, Providence College, Providence, Rhode Island 02918, USA.
Nat Commun. 2015 Sep 1;6:8158. doi: 10.1038/ncomms9158.
Physonect siphonophores are colonial cnidarians that are pervasive predators in many neritic and oceanic ecosystems. Physonects employ multiple, clonal medusan individuals, termed nectophores, to propel an aggregate colony. Here we show that developmental differences between clonal nectophores of the physonect Nanomia bijuga produce a division of labour in thrust and torque production that controls direction and magnitude of whole-colony swimming. Although smaller and less powerful, the position of young nectophores near the apex of the nectosome allows them to dominate torque production for turning, whereas older, larger and more powerful individuals near the base of the nectosome contribute predominantly to forward thrust production. The patterns we describe offer insight into the biomechanical success of an ecologically important and widespread colonial animal group, but, more broadly, provide basic physical understanding of a natural solution to multi-engine organization that may contribute to the expanding field of underwater-distributed propulsion vehicle design.
管水母目钟泳亚目动物是群居的刺胞动物，在许多浅海和海洋生态系统中都是常见的捕食者。管水母目钟泳亚目动物利用多个克隆的水母个体（称为泳钟体）来推动聚集的群体。我们在此表明，管水母目钟泳亚目动物Nanomia bijuga的克隆泳钟体之间的发育差异产生了推力和扭矩产生方面的分工，从而控制整个群体游泳的方向和幅度。尽管较年轻的泳钟体较小且力量较弱，但它们在泳钟囊顶端附近的位置使其能够主导转弯时的扭矩产生，而在泳钟囊底部附近的较年长、较大且力量更强的个体则主要贡献向前的推力产生。我们所描述的这些模式有助于深入了解一个在生态上重要且分布广泛的群居动物群体在生物力学方面的成功，但更广泛地说，能为多引擎组织的自然解决方案提供基本的物理理解，这可能有助于推动水下分布式推进车辆设计这一不断发展的领域。
