Taylor Dispersion: The Physics of Long-Range Signaling in a Single Cell

Diffusion alone is too slow for whole-body coordination in a large Physarum network. Taylor dispersion solves that speed problem by combining diffusion with oscillatory flow advection.

The result is rapid signal spread across long distances inside one giant cell.

Why diffusion is not enough

Pure diffusion moves molecules down concentration gradients, but transport time grows quickly with distance. In a sprawling tubular network, that can become a severe communication bottleneck.

Physarum avoids this by running rhythmic shuttle flow through its veins.

How Taylor dispersion emerges

When molecules are carried by pulsatile flow while also diffusing across streamlines, effective dispersion increases beyond diffusion-only expectation. In Physarum, rhythmic contractions repeatedly drive this mixing and transport process.

So the signaling medium is not passive. It is actively circulated.

Interaction with adaptation

Transport and structure co-evolve.

• High-flow routes carry more signal and resource traffic.
• Those routes are often reinforced structurally.
• Reinforcement further improves transport efficiency.

This feedback helps create fast long-range coordination and a physical memory of useful routes.

Why this matters for behavior

Attractant detection at one region can influence distant regions quickly because flow-assisted signaling propagates faster than local diffusion would allow.

That supports distributed decision behavior: global reconfiguration from local stimulus without centralized control.

Related reading: Peristaltic Pump, Windkessel Motif, and Physical Memory Coding.

Origin and E-E-A-T

This article summarizes editorial synthesis of Physarum transport studies describing advection-enhanced molecular spread under oscillatory shuttle flow, often interpreted through Taylor-dispersion logic. We frame claims in physically testable transport terms. Reviewed on 2026-02-11, version 1.0.0.