Bio-imitaiton of Mexican migration routes to the USA with slime mould on 3D terrains

TL;DR

This study uses slime mould to biologically model and analyze Mexican migration routes to the USA on 3D terrains, revealing how elevation influences migration network development.

Contribution

It introduces a novel bio-physical approach using slime mould to simulate and study human migration patterns on realistic terrains.

Findings

Elevation impacts migration route development

Slime mould networks resemble actual migration pathways

Topological features of routes are consistent with geographic data

Abstract

Plasmodium of Physarum polycephalum is a large single cell visible by unaided eye. It shows sophisticated behavioural traits in foraging for nutrients and developing an optimal transport network of protoplasmic tubes spanning sources of nutrients. When placed in an environment with distributed sources of nutrients the cell 'computes' an optimal graph spanning the nutrients by growing a network of protoplasmic tubes. P. polycephalum imitates development of man-made transport networks of a country when configuration of nutrients represents major urban areas. We employ this feature of the slime mould to imitate mexican migration to USA. The Mexican migration to USA is the World's largest migration system. We bio-physically imitate the migration using slime mould P. polycephalum. In laboratory experiments with 3D Nylon terrains of USA we imitated development of migratory routes from Mexico-USA border to ten urban areas with high concentration of Mexican migrants. From results of laboratory experiments we extracted topologies of migratory routes, and highlighted a role of elevations in shaping the human movement networks.