Csermely Davide
Dipartimento di Biologia Evolutiva e Funzionale, Sezione Museo di Storia Naturale, Università di Parma, via Farini 90, 43100 Parma, Italy.
Behav Processes. 2004 Nov 30;67(3):511-20. doi: 10.1016/j.beproc.2004.08.008.
Lateralisation, the different use of one or other side or appendix of the body, is basically determined by brain asymmetry which, in turn, is likely to be due to adaptive reasons. Several studies have been carried out on birds in general. However, birds of prey in particular, although they are very good candidates, have not been investigated from the sensory lateralisation point of view. In fact, many species scan for prey while perched and capture terrestrial prey with the feet, having at the same time the obvious necessity to keep their balance. This paper, therefore, investigates the existence of some sort of lateralisation in several species of both Falconiformes and Strigiformes temporarily in captivity. Attention is given to: (a) the direction of body rotation when perceiving a sound stimulus from behind the body and (b) the use of the feet when grasping a terrestrial prey. Lateralisation was found to be clearly present in both types of tests, although with some difference in its expression. In fact, almost every species tested rotated its body anti-clockwise, i.e. to the left, both in the first test and in repeated tests, with no noticeable difference between Falconiformes and Strigiformes. Also prey grasping showed a preferential use of one foot. Falconiformes preferred clearly to grasp the prey with one foot only in both the first test and in subsequent ones. Strigiformes, on the other hand, preferred using both feet, although a not insignificant proportion of individuals used one foot. Only the little owl seemed to have the tendency to prefer to use the right foot only, in a similar manner to Falconiformes. In fact, this bird is the most "diurnal" owl species among those tested, suggesting that lateralisation in footedness might be affected by adaptive constraints more than by phylogenetic similarities. Lateralisation, therefore, seems to be very widespread among birds of prey. Preferential use of the right foot also appears to be a general habit, and this is probably connected to the use of left hemisphere when manipulating food items.
偏侧化，即身体一侧或附属器官的不同使用方式，基本上由大脑不对称性决定，而大脑不对称性反过来可能是出于适应性原因。总体上已经对鸟类进行了多项研究。然而，猛禽尤其如此，尽管它们是很好的研究对象，但尚未从感官偏侧化的角度进行研究。事实上，许多猛禽在栖息时搜寻猎物并用脚捕捉地面猎物，同时显然需要保持平衡。因此，本文研究了几种暂时圈养的隼形目和鸮形目猛禽中是否存在某种偏侧化现象。研究重点关注：(a) 当从身体后方感知声音刺激时身体旋转的方向，以及 (b) 抓取地面猎物时脚的使用情况。在两种测试中都明显发现了偏侧化现象，尽管其表现存在一些差异。事实上，几乎每一个被测试的物种在第一次测试和重复测试中身体都逆时针旋转，即向左旋转，隼形目和鸮形目之间没有明显差异。抓握猎物时也显示出对一只脚的优先使用。隼形目在第一次测试和后续测试中都明显更喜欢只用一只脚抓取猎物。另一方面，鸮形目更喜欢用两只脚，尽管有相当一部分个体只用一只脚。只有纵纹腹小鸮似乎有只偏好使用右脚的倾向，与隼形目类似。事实上，这种鸟是被测试的鸮类中最“昼行性”的物种，这表明足部偏侧化可能更多地受到适应性限制的影响，而非系统发育相似性的影响。因此，偏侧化似乎在猛禽中非常普遍。优先使用右脚似乎也是一种普遍的习惯，这可能与在处理食物时使用左半球有关。
