ABSTRACT

Brain lateralization is generally considered adaptive for an individual and it can be ascertained, for example, by measuring the preferential use of limbs. Avian models have been extensively used to investigate the evolution and the advantages of brain lateralization. Birds of prey are a good model to study motor laterality, however to date they have been studied almost exclusively in the context of predatory behaviour. In this study, we tested lateralization in Gyrfalcon (Falco rusticolus) across multiple contexts, and collected the following measures:(1) standing leg preference when sleeping, (2) wing preference to position the head while sleeping and (3) leg preference to grasp food. At the population level, we found left-leg lateralization while sleeping and no preference for placing the head under the left or the right wing. In the context of the predatory behaviour, we found a trend towards using the left leg to grasp food. Across the behaviours observed, we did not find evidence of lateralization at an individual level, as most of the subjects were ambidextrous. This study highlights the importance of the behavioural context when investigating side-bias and hemispheric laterality.

摘要

大脑偏侧化通常被认为对个体具有适应性，并且可以通过例如测量肢体的优先使用来确定。鸟类模型已被广泛用于研究大脑侧化的进化和优势。猛禽是研究运动偏侧性的一个很好的模型，但迄今为止，它们几乎只在掠食行为的背景下进行了研究。在这项研究中，我们测试了 Gyrfalcon ( Falco rusticolus) 跨多个上下文，并收集了以下测量值：(1) 睡觉时站立腿偏好，(2) 睡觉时翅膀偏好定位头部和 (3) 腿偏好抓住食物。在人群水平上，我们发现睡觉时左腿偏侧，并且不喜欢将头部放在左翼或右翼下方。在掠夺性行为的背景下，我们发现了使用左腿抓取食物的趋势。在观察到的行为中，我们没有发现个体水平偏侧化的证据，因为大多数受试者都是灵巧的。这项研究强调了在调查侧偏和半球偏侧性时行为背景的重要性。