Zoology II, Biocenter, University of Würzburg, Am Hubland 1, 97074 Würzburg, Germany.
Zoology II, Biocenter, University of Würzburg, Am Hubland 1, 97074 Würzburg, Germany.
Curr Biol. 2022 Jan 24;32(2):338-349.e5. doi: 10.1016/j.cub.2021.11.009. Epub 2021 Nov 24.
For navigation, animals use a robust internal compass. Compass navigation is crucial for long-distance migrating animals like monarch butterflies, which use the sun to navigate over 4,000 km to their overwintering sites every fall. Sun-compass neurons of the central complex have only been recorded in immobile butterflies, and experimental evidence for encoding the animal's heading in these neurons is still missing. Although the activity of central-complex neurons exhibits a locomotor-dependent modulation in many insects, the function of such modulations remains unexplored. Here, we developed tetrode recordings from tethered flying monarch butterflies to reveal how flight modulates heading representation. We found that, during flight, heading-direction neurons change their tuning, transforming the central-complex network to function as a global compass. This compass is characterized by the dominance of processing steering feedback and allows for robust heading representation even under unreliable visual scenarios, an ideal strategy for maintaining a migratory heading over enormous distances.
对于导航，动物使用强大的内部罗盘。罗盘导航对于像帝王蝶这样的长途迁徙动物至关重要，它们每年秋天都会利用太阳导航超过 4000 公里到达越冬地。中央复合体内的太阳罗盘神经元仅在不动的蝴蝶中被记录到，而这些神经元中动物头部方向编码的实验证据仍然缺失。尽管中央复合体内神经元的活动在许多昆虫中表现出对运动的依赖性调节，但这种调节的功能仍未被探索。在这里，我们通过对系留飞行的帝王蝶进行四极管记录，揭示了飞行如何调节航向表示。我们发现，在飞行过程中，航向神经元改变了它们的调谐，将中央复合网络转化为一个全局罗盘。这个罗盘的特点是主导处理转向反馈，即使在不可靠的视觉场景下，也能实现稳健的航向表示，这是维持远距离迁徙航向的理想策略。
