Bioelectrical synchronization of Picea abies during a solar eclipse

" By comparing direct and time-reversed cross-correlation functions of the bioelectrical potentials, our modelling adequately corroborates our experimental findings, which support the vision of the forest as a correlated (collective) system. Although the environment significantly impacts the individual state and bioelectrical response of trees, their inter-connectivity, as evidenced by correlations and synchronized activity, suggests a more cohesive, organism-like response at the forest level. By virtue of synchronized individual responses, the forest reproduces the different stages of the individual’s responses to the changing conditions to respond to an event like the solar eclipse." {Credits 1}

" Patterns of synchronous activity have been observed in almost every animal group studied [76]. Notably, synchronized behaviour fundamentally involves the synchronization of movements [77]. Hence, likely due to their sessile nature, behavioural synchronization in plants has remained unexplored (and we are not concerned with phenological synchronization on the well-known circadian or seasonal timescales, such as masting [78], flowering [79] or oscillatory motions of stems and leaves [80]). By monitoring the electrome of spruce trees in their natural environment during the eclipse, our study provides evidence that trees display synchronized alterations in their bioelectrical activity patterns. Prior to this synchronized behaviour, the trees exhibited anticipation, a critical feature of synchronization behaviour displayed by many animal species that makes synchrony distinguishable from repetitive reactions to repetitive stimulation [77]. Specifically, the trees anticipated the solar eclipse by changing their bioelectrical behaviour several hours before the actual onset of the celestial event, which could cause substantial perturbations, such as drops in sap flow rates within trees [11] and disruptions in their vital hydraulic connection between the soil and the atmosphere [81]." {Credits 1}

" While solar eclipses may seem rare from a human perspective, they follow cycles, such as the Saros cycle, which can occur well within the lifespan of long-lived trees. This predictability suggests that solar eclipses, despite their infrequency, are not perceived as random events by trees. Instead, long-lived trees may have developed mechanisms to anticipate and respond to these events, similar to their responses to seasonal changes. Our findings support this hypothesis, as older trees exhibited greater anticipatory behaviour during the eclipse, possibly reflecting environmental patterns established over time. The synchronization and early time asymmetry observed in older trees reinforce the notion that rare but recurring events, like solar eclipses, are integrated into the biological dynamics of these organisms." {Credits 1}

{Credits 1} 🎪 Alessandro Chiolerio, Monica Gagliano, Silvio Pilia, Paolo Pilia, Giuseppe Vitiello, Mohammad Dehshibi, Andrew Adamatzky; Bioelectrical synchronization of Picea abies during a solar eclipse. R Soc Open Sci. 1 April 2025; 12 (4): 241786. https://doi.org/10.1098/rsos.241786. © 2025 The Author(s). This article is licensed under a Creative Commons Attribution License.