The ability to react and change body position, with maximum rate of force production, in all planes of motion, and from all body positions during functional activities is quickness.<span> How quick one can assess visual, auditory, or kinesthetic stimuli and provide the appropriate physical response denotes his quickness. Other parameters for measuring performance are agility and speed.</span>
Natural selection is a mechanism of evolution. Organisms that are more adapted to their environment and are more likely to survive and pass on the genes that aided their success. This process causes species to change and diverge over time.
