The Fractal Gene

When you look at trees, cauliflower and blood vessels you can see an intricate pattern with a unique property called fractalness. In simple terms, a fractal is a pattern that when you zoom into it, the pattern reappears across all scales. Thus, for examples, each tree species has its own branching angle to its branches, smaller branches, leaves and veins within the leaves. Similarly, cauliflower has "bumps", wherein each bump has smaller ones with the same proportions deeper and deeper. Our blood vessels are also patterned in a similar fashion.

These biological properties of living organisms develop as a result of the genetic code. In each of our cells, we have a whole copy of our genetic code, and during development, and also in adulthood, patterns emerge according to "blueprints" in our DNA. Thus, each cell knows if to become a liver cell, an endothelial cell in a blood vessel or a neuron in the brain. The development of blood vessels, as well as sprouting of branches and leaves, is (mostly) dictated by the genetic code.

One can also look at it from an information point-of-view. Fractals are very "compact" information-wise, i.e. with a simple code, or formula, one can code beautiful intricate designs. The complex structure of a tree, from its trunk up to its leaves' veins, can be "coded" in a single gene that regulates the branching ratio in all these levels. Blood vessels might also conform to this strategy, to encode complex intricate webs in our body by a single (or a small number of) genes.

Wouldn't it be wonderful to discover this "fractal gene"? Is it a single gene for each species, dictating the branching ratio? Is it a single complex of genes across species, whose ratio in each specie dictate the emerging pattern?

Perhaps discovering this wondrous "fractal gene" can help designing complex artificial patterns. Maybe coding this ratio in the design of nano-structures, such as carbon nanotubes, will enable self-assembly of complex fractal patterns of tubes. Perhaps, even, these structures will be stronger and have unique properties.

One caveat to this hypothesis, though. Fractals appear even in inanimate objects, such as clouds, mountains and riverbeds. These amazing patterns emerge through interaction of complex phenomena, without any "guidance" of biological control. There is the possibility that tree-shapes, as well as our blood vessels architecture, are the emergent property of the opposing interaction of growth, resources and gradients of chemicals in their surroundings. Probably, as in all these gene-environment discussions, the answer is somewhere in the middle. Yet this implies that there is such a "fractal gene", and it might play a role in the buildup of some of the most beautiful structures in nature.