Showering as a coolant for rats exposed to heat.

Rats exposed to heat learn to take showers and thus defend themselves against hyperthermia; thereafter the rate of showering is a direct function of ambient temperature. The showering effectively replaces spreading of saliva as the major defense against heat in desalivate rats, and appears to be highly preferred to the use of saliva by the intact animal. Since rats will work to obtain heat when cold, it is now clear that learned behavior is effective and physiologically appropriate for thermoregulation at temperatures both above and below the neutral range.