Bioelectrical synchronization of Picea abies during a solar eclipse

Regular light–dark cycles greatly affect organisms, and events like eclipses induce distinctive physiological and behavioural shifts. While well-documented in animals, plant behaviour during eclipses remains largely unexplored. Here, we monitored multiple spruce trees to assess their individual and collective bioelectrical responses to a solar eclipse. Trees anticipated the eclipse, synchronizing their bioelectrical behaviour hours in advance. Older trees displayed greater anticipatory behaviour with early time-asymmetry and entropy increases. These results reveal a relationship between trees, shaped by individual age and physiology as well as collective history. This highlights the significance of synchrony in plants, offering new insights into coordinated behaviours in nature.