Department of Psychology, University of Cambridge, Cambridge, United Kingdom.
PLoS One. 2013 Apr 17;8(4):e61174. doi: 10.1371/journal.pone.0061174. Print 2013.
Recent research suggests that domesticated species--due to artificial selection by humans for specific, preferred behavioral traits--are better than wild animals at responding to visual cues given by humans about the location of hidden food. \Although this seems to be supported by studies on a range of domesticated (including dogs, goats and horses) and wild (including wolves and chimpanzees) animals, there is also evidence that exposure to humans positively influences the ability of both wild and domesticated animals to follow these same cues. Here, we test the performance of Asian elephants (Elephas maximus) on an object choice task that provides them with visual-only cues given by humans about the location of hidden food. Captive elephants are interesting candidates for investigating how both domestication and human exposure may impact cue-following as they represent a non-domesticated species with almost constant human interaction. As a group, the elephants (n = 7) in our study were unable to follow pointing, body orientation or a combination of both as honest signals of food location. They were, however, able to follow vocal commands with which they were already familiar in a novel context, suggesting the elephants are able to follow cues if they are sufficiently salient. Although the elephants' inability to follow the visual cues provides partial support for the domestication hypothesis, an alternative explanation is that elephants may rely more heavily on other sensory modalities, specifically olfaction and audition. Further research will be needed to rule out this alternative explanation.
最近的研究表明，由于人类对特定、偏好的行为特征进行了人工选择，家养物种比野生动物更善于对人类关于隐藏食物位置的视觉线索做出反应。\虽然这似乎得到了对一系列家养动物（包括狗、山羊和马）和野生动物（包括狼和黑猩猩）的研究的支持，但也有证据表明，与人类的接触会积极影响野生动物和家养动物跟随这些相同线索的能力。在这里，我们测试了亚洲象（Elephas maximus）在一项物体选择任务中的表现，该任务为它们提供了人类关于隐藏食物位置的仅视觉线索。圈养大象是研究驯化和人类接触如何影响线索跟踪的有趣候选者，因为它们代表了一种非驯化物种，与人类几乎持续互动。作为一个群体，我们研究中的 7 头大象（n = 7）无法像诚实的食物位置信号那样跟随指示、身体朝向或两者的组合。然而，它们能够在新环境中遵循它们已经熟悉的声音命令，这表明如果线索足够明显，大象能够跟随线索。虽然大象无法跟随视觉线索部分支持了驯化假说，但另一种解释是，大象可能更依赖其他感觉模态，特别是嗅觉和听觉。需要进一步的研究来排除这种替代解释。
