2024/03/05 by Maximilian Kurjahn, Kurjahn, Maximilian, Leila Abbaspour +11 · 1 citation
Engineering · Physics and Astronomy · #Advanced Materials and Mechanics #Biological Physics (physics.bio-ph) #FOS: Physical sciences #Micro and Nano Robotics #Modular Robots and Swarm Intelligence #Soft Condensed Matter (cond-mat.soft)
paper · pdf · doi:10.48550/arxiv.2403.03093
openalex publication_date 2024/03/05 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Motility coupled to responsive behavior is essential for many microorganisms to seek and establish appropriate habitats. One of the simplest possible responses, reversing the direction of motion, is believed to enable filamentous cyanobacteria to form stable aggregates or accumulate in suitable light conditions. Here, we demonstrate that filamentous morphology in combination with responding to light gradients by reversals has consequences far beyond simple accumulation: Entangled aggregates form at the boundaries of illuminated regions, harnessing the boundary to establish local order. We explore how the light pattern, in particular its boundary curvature, impacts aggregation. A minimal mechanistic model of active flexible filaments resembles the experimental findings, thereby revealing the emergent and generic character of these structures. This phenomenon may enable elongated microorganisms to generate adaptive colony architectures in limited habitats, or guide the assembly of biomimetic fibrous materials.