 Nevertheless, humans do generally develop a specific set of physiological features, such as two lungs, one stomach, one pancreas and two eyes. Moreover, having such a bodily architecture is, according to the evidence from genetics, to a significant extent the result of developmental programmes that ground in gene regulatory networks (GRNs). These are stretches of non-coding DNA that regulate gene transcription. GRNs are modular, more or less strongly entrenched structures. The most highly conserved of these tend to be the phylogenetically most archaic (Carroll 2000; Walsh 2006: 436ff.; Willmore 2012: 227ff.). The GRNs responsible for basic physiological features may be taken, in a fairly innocuous sense, to belong to an evolved human nature.