David A. Tanzer, December 29, 2020
A leaf as a tree of pipes
Last time we set out the model of a leaf as a set of square cells in the plane. But there’s more structure to be defined: the veins.
All the veins taken together make up a ‘transport system’ for pumping fluid from the root to each of the cells.
Biological note: The cells need water to do … Read more
David A. Tanzer, December 25, 2020
Leaf shape: an optimization in nature
On this Christmas day, let us take a moment to think of the tree, and wonder how it actually grows. Slowly move your attention to the leaves, and ponder how they grow. Next, forget about this type of leaf, for a conifer, with parallel veins — as our true subject is the growth of leaves with branching veins. … Read more