Over short distances, substances can be transported through mycelial networks on a network of microtubules—dynamic filaments of protein that behave like a cross between scaffolding and escalators. Transport using microtubule «motors» is energetically costly, however, and over larger distances the contents of hyphae travel on a river of cellular fluid. Both approaches allow rapid transport across mycelial networks. Efficient transport allows different parts of a mycelial network to engage in different activities. When the English country house Haddon Hall was being renovated, a fruiting body of the dry-rot fungus Serpula was found in a disused stone oven. Its mycelial connections wound back through eight meters of stonework to a rotting floor elsewhere in the building. The floor was where it fed, the oven was where it fruited. The best way to appreciate flow within mycelium is to watch its contents shuttle around the network. In 2013, a group of researchers at the University of California at Los Angeles treated mycelium so that they could visualize cellular structures moving within the hyphae. Their videos show hordes of nuclei surging along. In some hyphae they travel faster than in others, in some they travel in different directions. Sometimes traffic jams form and nuclear traffic is rerouted on hyphal slip channels. Streams of nuclei merge with each other. Rhythmic pulses of nuclei—«nuclear comets»—rush along, branching at junctions and darting down side ducts. It is a scene of «nuclear anarchy,» as one of the researchers wryly observed.

Sheldrake, Merlin. Entangled Life (pp. 61-62). Random House Publishing Group. Kindle Edition.

Video: Nuclear dynamics in a fungal chimera

[Filamentous fungi (molds) are made up of a mass of growing, tube-like hyphae. Each extending hyphal tip is fed by a continuous flow of nuclei from the colony interior. Within the colony, these flows become complex and multidirectional, like traffic in a city. Paper: Marcus Roper, Anna Simonin, Patrick C. Hickey, Abby Leeder, and N. Louise Glass PNAS first published July 16, 2013; https://doi.org/10.1073/pnas.1220842110](https://youtu.be/_FSuUQP_BBc)

Filamentous fungi (molds) are made up of a mass of growing, tube-like hyphae. Each extending hyphal tip is fed by a continuous flow of nuclei from the colony interior. Within the colony, these flows become complex and multidirectional, like traffic in a city. Paper: Marcus Roper, Anna Simonin, Patrick C. Hickey, Abby Leeder, and N. Louise Glass PNAS first published July 16, 2013; https://doi.org/10.1073/pnas.1220842110

This fungus cell only looks like the 405 freeway

Video source

Mycelium Microscopy Shotsmpg

https://youtu.be/EufwIRqAHkc

For comparison: electron micrographs from ~2011, source unknown.