Meeting Abstract
Suction feeding is the most common prey capture strategy across teleosts. However, the intensity of the suction flow is constrained by the fish’s ability to produce fast movements as muscles contract slowly and over small distances. During rapid movements, tendons can act like springs, temporarily storing work done by muscles and then releasing it to power body movements. This is known as power amplification and the only known example in fish, is pivot feeding in the Syngnathidae family, whose members are able to rotate their snout towards the prey at exceptionally high speeds of ~20000°s-1. While the mechanism of power amplification that permits these exceptional speeds is well documented, the consequences of power amplification for suction feeding are poorly understood. Using a high-speed flow visualization technique, we characterized the spatio-temporal patterns in the flow fields produced during pivot feeding in 3 species of the Syngnathidae family. We discovered that due to power amplification, the Syngnathidae were able to create 8x greater flow velocities than similar-sized fish without this mechanism. The measurements from the flow fields were used to estimate the pressure fields in front of the mouth and calculate net suction power (power used to accelerate the water outside of the mouth). The power used for suction feeding was found to closely match the available power within the tendon of the sternohyoideus muscle, suggesting dyad power amplified system. This allows for the rapid head rotation buy the epaxial tendon and 8x greater flow velocities, compared to fish with no such mechanism, from the sternohyoideus muscle tendon. As far as we are aware, this is the first documented duel power amplified biomechanical system used for separate functions simultaneously!
