An expressed trait that is controlled by a multiple genes, i.e. a gene network. Contrast with monogenic.

The problem with gene networks is they greatly complicate the traditional Darwinian view of evolutionary progress through random mutation-and-selection. Random mutation , but surely there is clearly some kind of mathematical space that is being ‘explored’ as organisms radiate into ecosystem niches. We can also see that there is a relatively fixed bauplan that governs eukaryotes that was set hundreds of millions of years ago. These early evolutionary choices constrained the possible genetic spaces to be explored over the course of evolution.

Acknowledging this does not open up a space for intelligent design flat-earthers. It does open up a space for a Spinozan creator whose signatures we see in mathematics and its implementation in biology.