According to Zajonc’s (1965) motivation based theory, the presence of a conspecific should increase motivation and the effect of an increase in motivation should depend on the nature of the target behavior. If the target behavior is already in the animals repertoire, the presence of a conspecific should increase the target behavior. If, however, the target behavior needs to be acquired, it should retard its acquisition. There is evidence that pigeons will choose suboptimally when given a choice between a 20% chance of signaled reinforcement and a 50% chance of unsignaled reinforcement. Under these conditions, once a preference is found, Zajonc’s theory suggests that the presence of a conspecific should increase suboptimal choice. However, there is also evidence that social experience by pigeons outside the experimental context reduces suboptimal choice. In the present experiment, pigeons performed this task either in the presence of a conspecific or without a conspecific present. Inconsistent with Zajonc’s theory, the results indicated that pigeons that performed the task in the presence of a conspecific chose suboptimally less often than pigeons that performed the task on their own. The results suggest that the presence of a conspecific may provide an alternative source of reinforcement, thus replacing some of the effect of the conditioned stimulus provided by the signal for reinforcement. Further testing with increased experimental sample size is recommended to confirm these preliminary findings.

根据 Zajonc (1965) 的基于动机的理论，同种人的存在应该会增加动机，而动机增加的效果应该取决于目标行为的性质。如果目标行为已经存在于动物的全部能力中，那么同种动物的存在应该会增加目标行为。然而，如果需要获得目标行为，就应该延迟其获得。有证据表明，当鸽子在 20% 机会的信号强化和 50% 机会的无信号强化之间进行选择时，它们会做出次优选择。在这些条件下，一旦发现偏好，Zajonc 的理论表明，同种异体的存在应该会增加次优选择。然而，也有证据表明，实验环境之外的鸽子的社会经验减少了次优选择。在本实验中，鸽子在有同种动物存在或没有同种动物存在的情况下执行这项任务。与扎洪克的理论不一致的是，结果表明，在同种存在的情况下执行任务的鸽子比自己执行任务的鸽子做出次优选择的频率要低。结果表明，同种动物的存在可能提供替代的强化来源，从而取代强化信号提供的条件刺激的一些效果。建议增加实验样本量进行进一步测试，以证实这些初步发现。