Interesting experiments from the field of biology: researchers spread slime molds on a map of Tokyo and mark different city areas with food.

In just one day, this brainless protozoan automatically constructs a network—almost completely replicating Tokyo's existing railway system. No central control, no pre-planning, yet it produces an optimal layout.

This case really triggers reflection: complex systems don't necessarily require top-down design. Self-organization, emergence, and local interactions can give rise to global order. This logic can also be seen in crypto networks.