Peden B F, Rohe M S
J Exp Anal Behav. 1984 Sep;42(2):211-21. doi: 10.1901/jeab.1984.42-211.
An experiment determined whether pigeons minimize number of key pecks per food delivery and maintain their baseline intake of food while key pecking on a three-component chain schedule. Pigeons at either 80% or 100% body weight obtained all their food during baseline and contingency sessions. During baseline sessions, pecks on the left and center keys had no consequences; each peck on the right key activated the feeder. During contingency sessions, pigeons key pecked on a three-component chain schedule simulating components of a foraging chain. In the search component either 3, 9 or 15 key pecks (varied parametrically across blocks of sessions) on the left key produced a stimulus on the middle key, indicating an encounter with either the low-cost prey (3 key pecks) or an equally probable high-cost prey (21 key pecks). In the procurement component the pigeon pecked either: (a) the left key once, thus returning to the search component, or (b) the middle key either 3 or 21 times, which activated the right response key. In the handling component one peck on the right key operated the feeder. The pigeons always procured the low-cost prey and minimized the number of key pecks per hopper by procuring the high-cost prey when the search-cost ratio was high (15 key pecks) but not when it was low (3 key pecks). All pigeons maintained their baselines of eating during contingency sessions by key pecking more frequently and eating more efficiently. The 80% body-weight birds produced higher overall rates of key pecking and eating. These results have implications for ecological theories of optimal foraging and for psychological theories of learned performance.
一项实验确定了鸽子在按三分段链式程序啄键时，是否会尽量减少每次获得食物时的啄键次数，并维持其食物摄入量基线。体重为80%或100%的鸽子在基线期和应急期获得了它们所有的食物。在基线期，啄左边和中间的键没有任何结果；每次啄右边的键都会启动喂食器。在应急期，鸽子按照三分段链式程序啄键，模拟觅食链的各个部分。在搜索部分，在左边的键上啄3次、9次或15次（在不同的实验阶段块中参数化变化）会在中间的键上产生一个刺激，表明遇到了低成本猎物（3次啄键）或同等概率的高成本猎物（21次啄键）。在获取部分，鸽子要么：（a）啄一次左边的键，从而回到搜索部分，要么（b）啄中间的键3次或21次，这会激活右边的响应键。在处理部分，啄一次右边的键会操作喂食器。当搜索成本比高（15次啄键）时，鸽子总是获取低成本猎物，并通过获取高成本猎物来尽量减少每个料斗的啄键次数，但当搜索成本比低（3次啄键）时则不会。所有鸽子在应急期通过更频繁地啄键和更高效地进食来维持它们的进食基线。体重为80%的鸽子产生了更高的总体啄键和进食速率。这些结果对最优觅食的生态理论和学习表现的心理学理论具有启示意义。
