Path finding by tube morphogenesis in an amoeboid organism

We have studied how the plasmodium of Physarum polycephalum, a large amoebo id cell, is able to track the shortest path between two selected points in a labyrinth. When nutrients are supplied at these points to a sheet-like pl asmodium extended fully in a maze, the organism forms a single tube which c onnects the two sites via the shortest route. During the path finding, plas modial parts in dead ends of the maze shrink and finally the tube with the minimum-length is selected from the existing possibilities. A simple cellul ar mechanism based on interacting cellular rhythms may describe the experim ental observations. (C) 2001 Elsevier Science B.V. All rights reserved.