Kempinski, A. | Search bioRxiv

bioRxiv2026

Nonlinear distributed sensing of light patterns leads to perceptual distortions in plants

Many organisms lack centralized sensory-processing systems, navigating complex environments through local integration of spatially distributed stimuli (e.g., chemotaxis of cells, bacteria, or growing neurons). Here we propose the first general physical and geometric framework to describe how such distributed sensing translates into integrated directional responses. We study plants, multicellular decentralized systems that grow towards light (phototropism), which can come from multiple directions and at different intensities. We develop a model in which light is sensed locally on the shoot circumference, transduced nonlinearly, and integrated vectorially; the model is informed and validated by unilateral and bilateral lighting, and out-of-plane illumination experiments on sunflower seedlings. We show that seedlings respond to the vectorial sum of transduced signals rather than to the physical sum of incident light, which can create systematic deviations between maximal physical illumination and growth direction, akin to optical illusions. This framework further predicts that symmetrical, opposing cues cancel each other out, which we validate experimentally using a weaker symmetry-breaking light source.

plant biology↗

bioRxiv2022

Noise-mediated self-organization in mutually shading sunflowers

Circumnutations are widespread in plants and typically associated with exploratory movements, however a quantitative understanding of their role remains elusive. In this study we report, for the first time, the role of noisy circumnutations in facilitating an optimal growth pattern within a crowded group of mutually shading plants. We revisit the problem of self-organization observed for sunflowers, mediated by shade response interactions. Our analysis reveals that circumnutation movements conform to a bounded random walk characterized by a remarkably broad distribution of velocities, covering three orders of magnitude. In motile animal systems such wide distributions of movement velocities are frequently identified with enhancement of behavioral processes, suggesting that circumnutations may serve as a source of functional noise. To test our hypothesis, we developed a Langevin-type parsimonious model of interacting growing disks, informed by experiments, successfully capturing the characteristic dynamics of individual and multiple interacting plants. Employing our simulation framework we examine the role of circumnutations in the system, and find that the observed breadth of the velocity distribution represents a sharp transition in the force-noise ratio, conferring advantageous effects by facilitating exploration of potential configurations, leading to an optimized arrangement with minimal shading. These findings represent the first report of functional noise in plant movements, and establishes a theoretical foundation for investigating how plants navigate their environment by employing computational processes such as task-oriented processes, optimization, and active sensing. Since plants move by growing, space and time are coupled, and dynamics of self-organization lead to emergent 3D patterns. As such this system provides conceptual insight for other interacting growth-driven systems such fungal hyphae, neurons and self-growing robots, as well as active matter systems where agents interact with past trajectories of their counterparts, such as stigmergy in social insects. This foundational insight has implications in statistical physics, ecological dynamics, agriculture, and even swarm robotics. One sentence summary of paperThe study highlights noisy circumnutations as a strategy plants use for optimizing growth in crowded conditions.

plant biology↗