Professor and Head, Mathematical Physics Lab
The Rockefeller University
September 25, 2012
The architecture and plasticity of vascular systems: plant leaves, slime molds and the mammalian cortex.
Vascular systems, such as plant veins or the mammalian vasculature,, are well-known to be hierarchically organized, meaning they exhibit a large range of lenghtscales. Yet little is known about what evolutionary demands such hierarchical organization optimizes, or how to quantitatively describe their architecture. We concentrate on a number of vascular systems showing a hierarchically nested set of closed loops, such as the veins of plant leaves, the arteriole network of the cerebral cortex, or the reticular structure of fungii and slime molds. We have shown such loops serve the dual purpose of protecting the system against damage or failure of its parts, and balancing the delivery of nutrients when there are strong spatial fluctuations in the demand. We present methods to quantify the architectural structure of such networks, that permits us to clearly distinguish different organizational features in different species. Finally we discuss network plasticity: network remodeling based on feedback from the fluid flow, and its implications for development, maintenance and plasticity.