Meeting Abstract
A diversity of organisms rapidly protrude prehensile appendages to capture prey, including the tongues of lizards, salamanders, and frogs, and the tentacles of squid and cuttlefish. Cephalopods provide an interesting comparison to land-dwelling reptiles and amphibians, because the buoyancy of water can support greater appendage mass, yet drag costs are higher in water than in air. Using high-speed imaging (1000-3000 frames/s), we analyzed the strike behavior and kinematics of two species of cuttlefish, Sepia bandensis (n=6 individuals) and Metasepia pfefferi (n=3 individuals). Although both species have similar body sizes, S. bandensis have short, wide tentacles that they extend up to 2 times their body lengths, while the longer and slimmer tentacles of M. pfefferi can be extended up to 2.5 body lengths. Their tentacle extension exceeds rapid appendage protrusion in other species (maximum reported is 1.5 body lengths in Chameleo). In terms of strike kinematics, S. bandensis (34 strikes) reached lower maximum velocities (3 m/s) and accelerations (2000 m/s2) than M. pfefferi (4 m/s; 4000 m/s2; 14 strikes). Both cuttlefish species exceed the maximum velocities and accelerations reported for the squid Loligo pealei (2.3 m/s; 250 m/s2). M. pfefferi’s maximum velocities are comparable to the chameleon Chameleo outstati (4.9 m/s) and both cuttlefish species exceed the chameleon’s 392.8 m/s2 maximum acceleration. These findings suggest that the physical properties of water allow cuttlefish to achieve impressive velocities while extending soft, minimally-supported appendages much farther than their land-dwelling counterparts.
