People are more likely to comply with a large request when it is preceded by another, smaller request, and this is known as the “foot-in-the-door” (FITD). The FITD has been widely studied in social psychology and is thought to arise from mutually conflicting beliefs about past and present behavior (cognitive dissonance) or changes in self-perception. Across two experiments, we found that pigeons’ latency to respond to an effortful second stimulus in a pair scales with how much effort they had exerted on the first stimulus. As such, pigeons also display a FITD-like effect. We argue that the FITD may not be caused by conflicting beliefs or changes in self-perception but may instead be the product of behavioral contrast.

中文翻译：

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门上的爪子：鸽子像人类一样，表现出门上的效果。

当一个较大的请求之前出现另一个较小的请求时，人们更有可能遵守该请求，这被称为“现场行动”（FITD）。FITD已在社会心理学中进行了广泛的研究，并且被认为源于对过去和现在的行为（认知失调）或自我认知变化的相互矛盾的信念。在两个实验中，我们发现鸽子对一对努力的第二刺激的反应潜伏期与他们在第一刺激上所付出的努力成正比。这样，鸽子也表现出类似FITD的效果。我们认为，FITD可能不是由相互矛盾的信念或自我知觉的变化引起的，而可能是行为对比的产物。