Lehue Marine, Detrain Claire, Collignon Bertrand
Unit of Social Ecology, Université libre de Bruxelles, Brussels, Belgium.
Insects. 2020 May 21;11(5):317. doi: 10.3390/insects11050317.
The nest architecture of social insects deeply impacts the spatial distribution of nestmates their interactions, information exchanges and collective responses. In particular, the number of nest entrances can influence the interactions taking place beyond the nest boundaries and the emergence of collective structures like foraging trails. Here, we investigated in the field how the number of nest entrances impacted the foraging dynamics of ant colonies. We located the nest entrances where recruitment occurred towards sugar feeders placed in their surroundings. The nests showed one or multiple entrance(s) aggregated in clusters spaced by at least 15 cm. Foragers from colonies with two clusters of entrances were distributed more homogeneously among the feeders than those of colonies with one cluster. In addition, foragers always returned to the first discovered feeder and demonstrated a high fidelity to their original entrance. Finally, a multi-agent model highlighted that additional entrances and clusters of entrances delayed the mobilisation of workers but favoured the simultaneous exploitation of several sources, which was further enhanced by the spatial fidelity of foragers. Multiple nest entrances seem to be a way for medium-sized colonies to benefit from advantages conferred by polydomy while avoiding associated costs to maintain social cohesion.
群居昆虫的巢穴结构深刻影响着巢内成员的空间分布、它们之间的互动、信息交流以及集体反应。特别是，巢穴入口的数量会影响巢穴边界之外发生的互动以及诸如觅食路径等集体结构的出现。在此，我们在野外研究了巢穴入口数量如何影响蚁群的觅食动态。我们确定了在其周围放置糖源喂食器时，招募行为发生的巢穴入口位置。这些巢穴呈现出一个或多个入口，聚集在间隔至少15厘米的簇中。与具有一簇入口的蚁群相比，具有两簇入口的蚁群的觅食者在喂食器之间分布得更为均匀。此外，觅食者总是返回第一个发现的喂食器，并对其最初的入口表现出高度的忠诚度。最后，一个多智能体模型强调，额外的入口和入口簇会延迟工蚁的动员，但有利于同时利用多个食物源，而觅食者的空间忠诚度进一步增强了这种效果。多个巢穴入口似乎是中等规模蚁群从多巢优势中获益的一种方式，同时避免了维持社会凝聚力的相关成本。
