[kodisha]

You have a single cell that keeps dividing, and dividing, and in each division it becomes slightly different, and at the end some end up being the hart, some is the leg muscle, some are brain, and some are eye nerve.

Incredible, almost DIVINE..

The terraforming script behind this mechanism, is one of the most complex and most beautiful mechanism that exists in this universe.

[sfn42]

Cells in different locations produce different chemical markers. These markers spread out through the tissue and create a sort of gradient. By observing the gradient, a cell can know where it is (or at least what it's supposed to do).

At least that's the explanation as I've understood it.