Sh. Mitchell et J. Brener, THE WORK COSTS OF EARNING FOOD AS A DETERMINANT OF PATCH LEAVING, Journal of experimental psychology. Animal behavior processes, 23(2), 1997, pp. 136-144
Foraging theorists have long emphasized the role of the energy (work)
costs of food items on foraging behavior. However, few experiments hav
e measured this variable or demonstrated that animals are indeed sensi
tive to work costs. Experiment 1 assessed whether rats (Long-Evans) ca
n use the work costs of food to determine whether a food patch is exha
usted. Rats performed a fixed amount of work for each food item (fixed
-work [FW] schedule), but food was withheld unpredictably to simulate
sudden patch depletion. It was found that rats left patches only when
the work costs of unsuccessful searches (giving-up work) exceeded the
prevailing work costs of food. The time and response costs of unsucces
sful food searches (giving-up time and giving-up responses) were not p
redictive of patch leaving. Experiment 2 showed how rats regulated wor
k in this paradigm by examining the role of exteroceptive stimuli conn
ected with fulfilling the FW schedule.