The role of chemical footprints for foraging and competitive interactions in ants

许多动物根据环境中的线索来感知其他生物的存在。被捕食的生物可以从化学足迹、尿液或粪便等线索中发现捕食者，并改变它们的行为以减少被捕食的风险。这种行为反应的影响可能与直接捕食的影响一样强烈。与捕食者-猎物的相互作用相比，我们对竞争相互作用中的线索触发效应知之甚少。在这里，蚂蚁是一个特别合适的模型系统，因为它们在不同群体的成员之间表现出强烈的干扰竞争。最近，我们发现它们对其他种群的化学足迹做出反应，通过避开它们，接近它们或改变自己的攻击性。然而，健身的好处和社区水平的后果，以及决定这些行为反应的因素，几乎是完全未知的。在这里，我建议调查中欧蚂蚁物种对同种殖民和同种特异性足迹的反应的原因和后果。首先，我将评估足迹响应在蚂蚁黑蚁和金雀花的适应性后果。虽然M. rubra不分青红皂白地接近外国足迹，但L. niger具有高度歧视性，接近殖民地足迹，但避免外国同种生物的足迹。如果对外国足迹的反应有助于避免干扰竞争或开发竞争殖民地发现的食物来源的成本，那么这些反应可能是有益的。其次，我将研究化学足迹变化的作用和跨种群行为变化的作用。我将探索蚂蚁的区分能力，并确定反应差异是否取决于线索的化学差异。这在生态学上是相关的，特别是涉及到对新物种的反应，例如侵入性的Lasius neglect。在此背景下，我将研究对外来足迹的反应是否与群体特定的生活史特征、行为特征或以前与竞争对手的经历有关。最后，我将把这些问题扩展到群落水平，并研究共生蚂蚁物种之间的行为差异。这些研究将辅以基于主体的模型来模拟个体反应的紧急效应。在这里，我将研究不同的响应策略对群体适合度和群落组成的影响。拟议的项目在实证和模拟研究中将行为相互作用、化学生态学和群落生态学联系起来。它将为多个研究领域提供新的见解，包括群体行为，最佳觅食策略，化学感知和物种共存机制。

Many animals sense the presence of other organisms based on cues in the environment. Prey organisms can detect predators from cues like chemical footprints, urine or feces, and change their behaviour to reduce predation risk. The effects of such behavioural responses can be as strong as those of direct predation. In contrast to predator-prey interactions, very little is known on cue-triggered effects in competitive interactions. Here, ants are a particularly suitable model system since they show strong interference competition between members of different colonies. Recently, we showed that they respond to chemical footprints of other colonies, by avoiding them, approaching them or by altering their own aggressiveness. However, the fitness benefits and community-level consequences, as well as the factors that determine these behavioural responses, are almost completely unknown. Here, I propose to investigate causes and consequences of responses to allocolonial and allospecific footprints in Central European ant species. Firstly, I will assess fitness consequences of footprint responses in the ants Lasius niger and Myrmica rubra. While M. rubra indiscriminately approaches foreign footprints, L. niger is highly discriminatory, approaching concolonial footprints but avoiding those of foreign conspecifics. Responses to foreign footprints can be beneficial if they help to avoid costs from interference competition or to exploit food sources discovered by competing colonies.Secondly, I will investigate the role of chemical footprint variation and the role of behavioural variation across colonies. I will explore the ants' discriminatory ability and determine whether response differences depend on chemical differences of the cues. This is ecologically relevant especially concerning to responses to cues of novel species e.g. the invasive Lasius neglectus. In this context, I will investigate whether responses to foreign footprints are associated to colony-specific life-history traits, behavioural traits, or previous experience with competitors. Finally, I will extend these questions to the community level, and investigate behavioural variation between co-occuring ant species. The studies will be complemented by agent-based models to simulate emergent effects of individual responses. Here, I will examine the effects of different response strategies on colony fitness and community composition. The proposed project links behavioural interactions, chemical ecology and community ecology in empirical and simulation studies. It will provide novel insights into a multiple research fields, including swarm behaviour, optimal foraging strategies, chemical perception, and species co-existence mechanisms.