Going with the flow

The natural world is flush with structures that are both aesthetically pleasing and mechanically impressive. A case in point is the deep-sea sponge Euplectella aspergillum, which has an intricate and open skeletal structure that imbues the organism with exceptional flexibility and damage resistance. But there is more to this structure than its remarkable mechanical properties. Giacomo Falcucci and colleagues now bring the power of high-performance hydrodynamic simulations to bear on the fluid-dynamic properties of this sponge, and find that its framework also serves to reduce the hydrodynamic stresses that it will experience in deep-sea conditions, while modulating the internal fluid recirculation patterns in a manner that may prove beneficial for feeding and reproduction. More generally, these results highlight how complex geometries can result in fluid flow fields that have multiple functions, which could in turn inspire the design of multifunctional engineering structures.