Aquatic locomotion

Biologically propelled motion through a liquid medium

Aquatic locomotion or swimming is biologically propelled motion through a liquid medium. Swimming by different mechanisms has evolved repeatedly in organisms including arthropods, fish, molluscs, amphibians, reptiles, birds, and mammals. Many single-celled organisms including bacteria and ciliates use motile organelles, cilia or flagella, while others use pseudopodia, temporary projections of the cell body powered by the cytoskeletal protein actin.

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