Acclimatization is the process of an organism adjusting to changes in its environment, often involving temperature or climate (In laboratory conditions, this same process is termed "Acclimation"). Acclimatization usually occurs in a short time, and within one organism's lifetime (compare adaptation). This may be a discrete occurrence or may instead represent part of a periodic cycle, such as a mammal shedding heavy winter fur in favor of a lighter summer coat. Where acclimatization occurs naturally, some authors have used acclimation to describe the process of an organism being forced to adjust to changes in their environment by artificial means, such as in a laboratory setting.