This is all sorts of neat. Researchers Andrew Adamatzky and Ramon Alonso-Sanz are using a slime mold, P polycephalum, to find the most efficient road routes to provide guidance on how to rework them. P polycephalum is a single-celled organism that forages for food through various branches, and when it finds the most efficient food source, backs away from the others. The video above is a sped up version of it in action. Adamatzky and Alonso-Sanz put a map underneath.
We cut agar plates in a shape of Iberian peninsula, place oat flakes at the sites of major urban areas and analyse the foraging network developed. We compare the plasmodial network with principle motorways and also analyse man-made and plasmodium networks in a framework of planar proximity graphs.