P1160635 Marine iguana swimming
The swimming of a marine iguana resembles floating, as the animal's legs do not move. Nevertheless the change of position is very rapid and directed. Darwin described it like this: "When in the water this lizard swims with perfect ease and quickness, by a serpentine movement of its body and flattened tail — the legs being motionless and closely collapsed on its sides.", see "The Voyage of the Beagle. Chapter 17 — Galapagos Archipelago".