TUNA-ble Structures, Hydraulics, and Hydrodynamics.

Pacific Bluefin Tuna are highly efficient movers through water and have developed advanced hydrodynamic strategies. These fish feature a modified lymphatic system converted into a fine-tuned hydraulic fin-adjustment apparatus. This hydraulic mechanism features a series of compressible vessels and associated depressor muscles that selectively push fluid into an incompressible chamber where the liquid is pressurized and squirted into peanut-shaped channels within the fin. The result is a system that can adjust the stiffness and forward/aft rake as well as the lift profile of the fin.
Engineers and designers could develop fine-tuned hydraulic systems for applications requiring adjustable lift profiles, such as aviation, automotive, or marine transport.

This download NOW includes the 2-page, quick reference, Nature's Engineering Research Document (NERD) and explanation video.