In biology, the term motile refers to the ability of an organism or a cell to move spontaneously and actively. It describes organisms that can change their position or location through their own power rather than relying on external forces. This movement can be achieved through various means such as flagella, cilia, or muscle contractions.
For example, in the case of animals, motile organisms include those that can walk, swim, or fly, like fish, birds, and mammals. In the microbial world, motile bacteria can swim through liquid environments using flagella. The opposite of motile is non-motile, which describes organisms that are stationary and do not have the ability to move independently.
Understanding motility is crucial in various biological fields, including ecology, where the movement of organisms can influence populations and ecosystems, and microbiology, where motility can affect how bacteria spread and cause infections.