Acclimatization is the process by which an organism adjusts to changes in its environment, such as temperature, altitude, or humidity. This adaptation helps the organism maintain optimal functioning despite new conditions. For example, when people travel to high altitudes, their bodies gradually produce more red blood cells to improve oxygen delivery. This process can take days to weeks, depending on the severity of the environmental change. Acclimatization is crucial for survival in extreme conditions, as it allows organisms, including humans, to thrive in diverse habitats. It is different from evolution, which occurs over much longer timescales.