Collett Thomas S, Collett Matthew
School of Life Sciences, University of Sussex, Brighton, BN1 9QG, UK,
J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2015 Jun;201(6):617-30. doi: 10.1007/s00359-015-1001-z. Epub 2015 Apr 23.
Insects such as desert ants and honeybees use visual memories to travel along familiar routes between their nest and a food-site. We trained Cataglyphis fortis foragers along a two-segment route to investigate whether they encode the lengths of route segments over which visual cues remain approximately constant. Our results support earlier studies suggesting that such route-segment odometry exists, and allows an individual to stop using a visual route memory at an appropriate point, even in the absence of any change in the visual surroundings. But we find that the behavioural effects of route-segment odometry are often complicated by interactions with guidance from the global path-integration system. If route-segment odometry and path-integration agree, they act together to produce a precise signal for search. If the endpoint of route-segment odometry arrives first, it does not trigger search but its effect can persist and cause guidance by path-integration to end early. Conversely, if ants start with their path-integration state at zero, they follow a route memory for no more than 3 m, irrespective of the route-segment length. A possible explanation for these results is that if one guidance system is made to overshoot its endpoint, it can cause the other to be cut short.
诸如沙漠蚂蚁和蜜蜂之类的昆虫利用视觉记忆沿着巢穴与食物地点之间的熟悉路线行进。我们训练了厚结猛蚁觅食者沿着一条两段式路线行进，以研究它们是否对视觉线索大致保持不变的路线段长度进行编码。我们的结果支持了早期的研究，这些研究表明存在这种路线段里程测量法，并且即使在视觉环境没有任何变化的情况下，个体也能够在适当的点停止使用视觉路线记忆。但是我们发现，路线段里程测量法的行为效应常常因与全局路径积分系统的引导相互作用而变得复杂。如果路线段里程测量法和路径积分一致，它们会共同作用以产生精确的搜索信号。如果路线段里程测量法的终点先到达，它不会触发搜索，但其影响可能会持续并导致路径积分的引导提前结束。相反，如果蚂蚁从路径积分状态为零开始，无论路线段长度如何，它们沿着路线记忆行进的距离都不会超过3米。这些结果的一个可能解释是，如果一个引导系统越过其终点，它可能会导致另一个引导系统提前结束。
