The tiger shark uses its heterocercal tail as its primary source of propulsion, moving in an S-shaped fashion.
Tiger sharks have a heterocercal tail, meaning the dorsal lobe of the caudal fin is longer than the ventral lobe.
In tiger sharks, the heterocercal tail, or caudal fin, is the primary source of propulsion. The caudal fin produces a downward thrust of water behind the center of balance in a shark, which should cause its head to turn upwards. However, because the tail also moves side to side, it keeps the head from turning upwards. Because of this, tiger sharks move in an S-shaped fashion.
• Image | ©️ Albert Kok, Some Rights Reserved (CC BY-SA 3.0)
• Sources | (Draper, 2011; Essapian, 1962; Gruber & Myrberg, Jr., 1977; Heithaus, 2001; Heithaus, et al., 2007; Pratt, Jr., 1988; Read, 2010; Tang & Newbound, 2004; Thomson & Simanek, 1977)