Behavioral strategies in the cold: effects of feeding and nesting costs.
Animals can meet energetic challenges by acquiring or conserving energy. In the present experiment, we pitted these strategies against each other by housing rats in a cold environment and requiring them to bar press for food pellets and for access to a heated nest. Our question was how rats would exploit these resources to meet the added energetic demand of the cold when food was abundant or scarce. Results showed that rats' allocation of time and effort between competing activities was a function of demand. Feeding and nesting were partially substitutable in the cold: rats traded food for warmth and vice versa, economizing on both time and energy by adjusting their feeding and nesting patterns. Depending upon food abundance and the cost of nesting, rats acquired calories from food, conserved calories by nesting, and borrowed calories from the defense of body weight.
Schultz
L A
LA
Department of Psychology, Rutgers, The State University of New Jersey, Piscataway 08854-8020, USA.
Collier
G
G
Johnson
D F
DF
D000064:Acclimatization / Q000502:physiology*; D000818:Animals; D001835:Body Weight / Q000502:physiology; D003080:Cold Temperature; D002149:Energy Intake / Q000502:physiology; D004734:Energy Metabolism / Q000502:physiology*; D005247:Feeding Behavior / Q000502:physiology*; D006706:Homeostasis / Q000502:physiology; D008297:Male; D009042:Motivation; D009425:Nesting Behavior / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley