The Direction of the Thrust Produced by the Heterocercal Tails of Two Dissimilar Elasmobranchs: The Port Jackson Shark, Heterodontus Portusjacksoni (Meyer), and the Piked Dogfish, Squalus Megalops (Macleay)

Abstract

It is generally held that the heterocercal tail of elasmobranchs (as well as certain primitive osteichthyans) generates a thrust which is angled upwards. The thrust is thought of as resolved into a horizontal component which drives the animal forward, and a vertical component which aids in the levitation of the creature in the water.