Physarum can compute shortest paths.
Physarum polycephalum is a slime mold that is apparently able to solve shortest path problems. A mathematical model has been proposed by Tero et al. (Journal of Theoretical Biology, 244, 2007, pp. 553-564) to describe the feedback mechanism used by the slime mold to adapt its tubular channels while foraging two food sources s(0) and s(1). We prove that, under this model, the mass of the mold will eventually converge to the shortest s(0)-s(1) path of the network that the mold lies on, independently of the structure of the network or of the initial mass distribution. This matches the experimental observations by Tero et al. and can be seen as an example of a "natural algorithm", that is, an algorithm developed by evolution over millions of years.
Istituto di Analisi dei Sistemi ed Informatica Antonio Ruberti - CNR, Rome, Italy. vincenzo.bonifaci@iasi.cnr.it
Vincenzo
V
Bonifaci
Kurt
K
Mehlhorn
Girish
G
Varma
D008954:Models, Biological; D009068:Movement / Q000502:physiology*; D016839:Physarum polycephalum / Q000502:physiology*