Fleischmann Pauline N, Grob Robin, Wehner Rüdiger, Rössler Wolfgang
Behavioral Physiology and Sociobiology (Zoology II), Biozentrum, University of Würzburg, Am Hubland, Würzburg 97074, Germany
Behavioral Physiology and Sociobiology (Zoology II), Biozentrum, University of Würzburg, Am Hubland, Würzburg 97074, Germany.
J Exp Biol. 2017 Jul 1;220(Pt 13):2426-2435. doi: 10.1242/jeb.158147.
desert ants are famous navigators. Like all central place foragers, they are confronted with the challenge to return home, i.e. relocate an inconspicuous nest entrance in the ground, after their extensive foraging trips. When leaving the underground nest for the first time, desert ants perform a striking behavior, so-called learning walks that are well structured. However, it is still unclear how the ants initially acquire the information needed for sky- and landmark-based navigation, in particular how they calibrate their compass system at the beginning of their foraging careers. Using high-speed video analyses, we show that different species include different types of characteristic turns in their learning walks. Pirouettes are full or partial rotations (tight turns about the vertical body axis) during which the ants frequently stop and gaze back in the direction of the nest entrance during the longest stopping phases. In contrast, voltes are small walked circles without directed stopping phases. Interestingly, only ant species living in a cluttered, and therefore visually rich, environment (i.e. and in southern Greece) perform both voltes and pirouettes. They look back to the nest entrance during pirouettes, most probably to take snapshots of the surroundings. In contrast, inhabiting featureless saltpans in Tunisia perform only voltes and do not stop during these turns to gaze back at the nest - even if a set of artificial landmarks surrounds the nest entrance.
沙漠蚂蚁是著名的导航者。像所有中心地觅食者一样，它们在长途觅食之旅后面临着回家的挑战，即在地面上重新找到不显眼的巢穴入口。首次离开地下巢穴时，沙漠蚂蚁会表现出一种引人注目的行为，即结构良好的所谓学习行走。然而，蚂蚁最初是如何获取基于天空和地标导航所需信息的，尤其是它们在觅食生涯开始时如何校准其罗盘系统，目前仍不清楚。通过高速视频分析，我们发现不同物种在学习行走中包含不同类型的特征性转弯。旋转是完整或部分的旋转（围绕垂直身体轴的急转弯），在此期间蚂蚁经常停下来，在最长的停顿阶段回头看向巢穴入口的方向。相比之下，环行是小的行走圆圈，没有定向的停顿阶段。有趣的是，只有生活在杂乱且视觉丰富的环境（即希腊南部）中的蚂蚁物种既会进行环行也会进行旋转。它们在旋转时会回头看向巢穴入口，很可能是为了拍摄周围环境的快照。相比之下，生活在突尼斯无特征盐滩的蚂蚁只进行环行，并且在这些转弯过程中不会停下来回头看巢穴——即使巢穴入口周围有一组人工地标。
