I believe the answer is moderate temperature
Temperature will influence the structure of an molecule and the speed of enzyme. An organism will have an ideal temperature range where their cell can work efficiently, but the temperature of the environment could changes tremendously by the sunlight exposure. Water have high heat capacity and could provide a relatively more constant temperature which could protect the organism from immediate harm.
Water is essential to all living things. one important attribute of water allows it to maintain a constant environment within cells. Moderate temperature allows it to do this.
Temperature moderation is defined as the act of controlling or regulating the temperature. Fans and air conditioners are some of the ways of controlling temperatures.
