Konrad Lorenz Forschungsstelle, Grünau im Almtal, Austria.
Anim Cogn. 2011 Jul;14(4):477-85. doi: 10.1007/s10071-011-0381-x. Epub 2011 Feb 10.
Visual co-orientation with another's gaze direction (gaze following) may provide important information about the location of food, social interactions or predators. Gaze following has been shown in a variety of mammals, but only in few bird species, and has not been tested in precocial birds at all. It has been suggested that gaze following is an anti-predator behaviour, and in Common ravens (Corvus corax) and rooks (C. frugilegus), it emerges shortly after fledging, at a time when young birds leave the predator-safe nest. However, if gaze following is adaptive, the developmental pattern should differ between altricial and precocial birds. Greylag geese (Anser anser) are highly social birds with a precocial development. Goslings move and feed independently within 24 h post-hatching, and they are highly vulnerable to aerial predators. We therefore predicted that greylag geese are capable of gaze following and that they develop this skill already pre-fledging. We experimentally tested 19 hand-raised greylag goslings for their ability to follow a conspecific's gaze when they were between 10 days and 6 weeks old. In line with our predictions, first responses were already detectable in 10-day-old goslings. Our results therefore not only demonstrate that greylag geese follow the gaze of conspecifics into distant space, but that they also develop this ability much earlier than altricial birds.
与他人的目光方向（注视跟随）进行视觉协调可以提供有关食物、社交互动或捕食者位置的重要信息。在各种哺乳动物中都表现出了注视跟随，但在鸟类中只有少数物种表现出了这种行为，而在早成性鸟类中根本没有进行过测试。有人认为，注视跟随是一种反捕食行为，在普通乌鸦（Corvus corax）和松鸦（C. frugilegus）中，它在刚孵化后不久就会出现，此时幼鸟离开安全的巢穴。然而，如果注视跟随是适应性的，那么在晚成性和早成性鸟类之间，其发育模式应该有所不同。灰雁（Anser anser）是一种高度社会化的鸟类，具有早成性发育。鹅在孵化后 24 小时内即可独立移动和进食，并且极易受到空中捕食者的攻击。因此，我们预测灰雁能够进行注视跟随，并且它们在出巢前就已经具备了这种技能。我们通过实验测试了 19 只人工饲养的灰雁鹅，观察它们在 10 天到 6 周龄之间跟随同类目光的能力。与我们的预测一致，10 天大的鹅雏已经能够做出第一反应。因此，我们的研究结果不仅表明灰雁鹅会跟随同类的目光看向远处，还表明它们比早成性鸟类更早地发展出这种能力。
