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2010-09-03)
Fontanella, Janet E.; Fish, Frank E.; Rybczynski, Natalia; Nweeia, Martin T.; Ketten, Darlene R.
Cetaceans (whales, porpoises, and dolphins) use only their flukes for propulsion. Flukes are distally located extensions of the tail, and from a biomechanical standpoint, function as a pair of wings (Vogel 1994). Flukes function to produce thrust generated as an anteriorly directed lift force as flukes oscillate vertically (Fish 1998 a,b). Their cross-sections resemble hydrofoils. For a hydrofoil to be effective, a large lift must be produced while drag is minimized; this, in turn, increases the thrust generated (Weihs 1989; Vogel 1994).