Biological transportation networks
Transportation networks are fundamental infrastructures of man-made systems: urban streets, aqueducts, supply systems. Transportation networks also play an important role in many natural systems: foraging trails and underground galleries built by animals, vascular systems of plants and animals. In spite of their different origin, transportation networks all share some common features:
- an important role of spatial constraints. Either the nodes, or edges, or both are localized in the physical space and some kinds of connections may not be possible (long distance connections, or connections outside planarity)
- a dynamics of network evolution much slower than the dynamics of transportation processes taking place on top of the network. History of growth has an important role in determining network structure
- their efficiency is quantified by two well distinguished measures of cost: the cost of the infrastructure and the cost of transportation both natural selection (in the biological systems) and economic and logistic issues (in the human made systems) require that transportation networks be flexible and robust to variations in external conditions, such as traffic or failure of individual links
In 2010 Jean Baptiste Rouquier, Pascale Kuntz and myself organized a quite successful workshop on "Transportation Networks in Nature and Technology" of which a follow-up on a closely related subject was organized in 2011 at Stratchlyde University in Glasgow. The success of the workshop emphasizes the current interest in this topic.