what is the function of the fins in a squid
The paired tail fin is attached to the upper surface of the mantle and is made up of muscle. The colossal squid swims forward through the water by undulating the fin longitudinally. The fin is unusually massive and muscular (1,183 millimetres long and 982 millimetres wide). This probably enables the colossal squid to move forward quite rapidly in short bursts when attacking prey.