PDF(Pubmed)
Abstract：
Optical illusions have long been used in behavioural studies to investigate the perceptual mechanisms underlying vision in animals. So far, three studies have focused on ungulates, providing evidence that they may be susceptible to some optical illusions, in a way similar to humans. Here, we used two food-choice tasks to study susceptibility to the Müller-Lyer and Delboeuf illusions in 17 captive individuals belonging to four ungulate species (Lama guanicoe, Lama glama, Ovis aries, Capra hircus). At the group level, there was a significant preference for the longer/larger food over the shorter/smaller one in control trials. Additionally, the whole group significantly preferred the food stick between two inward arrowheads over an identical one between two outward arrowheads in experimental trials of the Müller-Lyer task, and also preferred the food on the smaller circle over an identical one on the larger circle in the experimental trials of the Delboeuf task. Group-level analyses further showed no significant differences across species, although at the individual level we found significant variation in performance. Our findings suggest that, in line with our predictions, ungulates are overall susceptible to the Müller-Lyer and the Delboeuf illusions, and indicate that the perceptual mechanisms underlying size estimation in artiodactyls might be similar to those of other species, including humans.
摘要：
光学错觉长期以来一直用于行为研究，以研究动物视觉的感知机制。到目前为止,三项研究集中在有蹄类动物上，提供证据表明他们可能容易受到一些视错觉的影响，在某种程度上类似于人类。这里,我们使用了两个食物选择任务来研究属于四种有蹄类动物的17个圈养个体对Müller-Lyer和Delboeuf错觉的易感性（Lamaguinicoe，格拉玛,OvisAries,Caprahircus）。在集团层面,在对照试验中,较短/较小的食物明显偏好较长/较大的食物.此外,在Müller-Lyer任务的实验试验中，整个小组明显更喜欢两个向内箭头之间的食物棒，而不是两个向外箭头之间的相同的食物棒。在Delboeuf任务的实验试验中，也更喜欢较小圆圈上的食物，而不是较大圆圈上的相同食物。群体水平分析进一步显示，不同物种之间没有显著差异，尽管在个人层面上，我们发现了表现上的显著差异。我们的研究结果表明,符合我们的预测，有蹄类动物总体上容易受到Müller-Lyer和Delboeuf错觉的影响，并表明偶蹄动物大小估计的感知机制可能与其他物种相似，包括人类。
