Collective behaviour is common in bacteria, plants and animals, and therefore occurs across ecosystems, from biofilms to cities. With collective behaviour, social interactions among individuals propagate to affect the behaviour of groups, whereas group-level responses in turn affect individual behaviour. These cross-scale feedback loops between individuals, populations and their environments can provide fitness benefits, such as the efficient exploitation of uncertain resources, as well as costs, such as increased resource competition. Although the social mechanics of collective behaviour are increasingly well-studied, its role in ecosystems remains poorly understood. Here we introduce collective movement into a model of consumer–resource dynamics to demonstrate that collective behaviour can attenuate consumer–resource cycles and promote species coexistence. We focus on collective movement as a particularly well-understood example of collective behaviour. Adding collective movement to canonical unstable ecological scenarios causes emergent social–ecological feedback, which mitigates conditions that would otherwise result in extinction. Collective behaviour could play a key part in the maintenance of biodiversity.

集体行为在细菌、植物和动物中很常见，因此发生在从生物膜到城市的整个生态系统中。通过集体行为，个体之间的社会互动传播以影响群体的行为，而群体层面的反应反过来影响个体行为。个体、群体及其环境之间的这些跨尺度反馈循环可以提供适应性益处，例如有效利用不确定资源，以及成本，例如增加资源竞争。尽管集体行为的社会机制得到越来越多的研究，但它在生态系统中的作用仍然知之甚少。在这里，我们将集体运动引入消费者-资源动态模型中，以证明集体行为可以减弱消费者-资源循环并促进物种共存。我们专注于集体运动作为集体行为的一个特别容易理解的例子。将集体运动添加到典型的不稳定生态场景中会导致紧急的社会生态反馈，从而缓解可能导致灭绝的条件。集体行为可以在维护生物多样性方面发挥关键作用。