Gerbier Grégory, Garnier Simon, Rieu Cécile, Theraulaz Guy, Fourcassié Vincent
Centre de Recherches sur la Cognition Animale, UMR CNRS 5169, Université de Toulouse, 118 route de Narbonne, 31062, Toulouse cedex 4, France.
Anim Cogn. 2008 Oct;11(4):637-42. doi: 10.1007/s10071-008-0153-4. Epub 2008 May 6.
The ability to orient and navigate in space is essential for all animals whose home range is organized around a central point. Because of their small home range compared to vertebrates, central place foraging insects such as ants have for a long time provided a choice model for the study of orientation mechanisms. In many ant species, the movement of individuals on their colony home range is achieved essentially collectively, on the chemical trails laid down by their nest mates. In the initial stage of food recruitment, these trails can cross each other and thus form a network of interconnected paths in which ants have to orient. Previous simulation studies have shown that ants can find the shortest path between their nest and a food source in such a network only if there is a bias in the branch they choose when they reach an asymmetrical bifurcation. In this paper, we studied the choice of ants when facing either a symmetrical or an asymmetrical bifurcation between two tunnels. Ants were tested either on their way to a food source or when coming back to their nest, and either in the presence or in the absence of a chemical trail. Overall, our results show that the choice of an ant at a tunnel bifurcation depends more on the presence/absence of a trail pheromone than on the geometry of the bifurcation itself.
对于所有活动范围围绕中心点组织起来的动物而言，在空间中定向和导航的能力至关重要。与脊椎动物相比，蚂蚁等中心地觅食昆虫的活动范围较小，长期以来一直是研究定向机制的理想模型。在许多蚂蚁物种中，个体在蚁群活动范围内的移动基本上是集体完成的，沿着巢伴留下的化学踪迹行进。在食物招募的初始阶段，这些踪迹可能相互交叉，从而形成一个相互连接的路径网络，蚂蚁必须在其中定向。先前的模拟研究表明，只有当蚂蚁到达不对称分支点时在它们选择的分支中有偏向时，它们才能在这样的网络中找到巢穴与食物源之间的最短路径。在本文中，我们研究了蚂蚁在面对两条隧道之间的对称或不对称分支时的选择。蚂蚁在前往食物源的途中或返回巢穴时接受测试，并且分别在有或没有化学踪迹的情况下进行测试。总体而言，我们的结果表明，蚂蚁在隧道分支点处的选择更多地取决于踪迹信息素的有无，而不是分支本身的几何形状。
