Zeil Jochen
Research School of Biology, The Australian National University, 46 Sullivans Creek Road, Canberra ACT2601, Australia.
J Exp Biol. 2025 Jan 15;228(2). doi: 10.1242/jeb.249499. Epub 2025 Jan 27.
Visually navigating Myrmecia foragers approach their nest from distances up to 25 m along well-directed paths, even from locations they have never been before ( Narendra et al., 2013). However, close to the nest, they often spend some time pinpointing the nest entrance, sometimes missing it by centimetres. Here, I investigated what guides homing ants in their attempt to pinpoint the nest entrance. As the ants approach the nest, their behaviour changes. At approximately 1 m from the nest, the ants slow down, their scanning amplitude becomes larger and their path direction changes more frequently. This change in scanning behaviour is not triggered by local olfactory, tactile or visual cues because ants tethered on a trackball 30-50 cm above ground also exhibit it at 0.6 m compared with 1.6 m distance from the nest. Moreover, the ants are able to pinpoint the nest when such local cues are removed by covering the ground around the nest or the nest entrance itself. Myrmecia ants thus rely on information from the global panorama when pinpointing the nest. During learning walks, these ants appear to systematically collect views directed toward and away from the nest ( Jayatilaka et al., 2018). Homing ants indeed change gaze and body axis direction appropriately with a delay when encountering views to the left or to the right of the nest. However, image analysis shows that close to the nest, opponent views with the same orientation become too similar, explaining the growing uncertainty reflected in the ants' increased scanning behaviour during homing.
视力良好的蜜蚁觅食者会沿着指向明确的路径，从最远25米的距离接近巢穴，即使是从它们从未去过的地方（纳伦德拉等人，2013年）。然而，在靠近巢穴时，它们常常会花些时间来确定巢穴入口的位置，有时会差几厘米而错过。在此，我研究了是什么引导归巢的蚂蚁试图确定巢穴入口的位置。当蚂蚁接近巢穴时，它们的行为会发生变化。在距离巢穴约1米处，蚂蚁会放慢速度，扫描幅度变大，路径方向变化更频繁。这种扫描行为的变化不是由局部嗅觉、触觉或视觉线索触发的，因为拴在离地面30 - 50厘米高的轨迹球上的蚂蚁，在距离巢穴0.6米时与距离1.6米时相比，也会表现出这种行为。此外，当通过覆盖巢穴周围地面或巢穴入口本身来去除这些局部线索时，蚂蚁仍能确定巢穴位置。因此，蜜蚁在确定巢穴位置时依赖于来自整体全景的信息。在学习行走过程中，这些蚂蚁似乎会系统地收集朝向和背离巢穴的视图（贾亚蒂拉克等人，2018年）。归巢的蚂蚁在遇到巢穴左侧或右侧的视图时，确实会适当地延迟改变注视方向和身体轴线方向。然而，图像分析表明，在靠近巢穴时，具有相同方向的相反视图变得过于相似，这就解释了归巢过程中蚂蚁扫描行为增加所反映出的越来越大的不确定性。
