While it's clear that the rakghoul virus initially spreads across the surface of a given planet, it has been difficult to determine the point of origin because the greatest density of rakghouls is not aboveground, but rather deep underground. Researchers attempting to understand why rakghouls congregate below a given planet's surface rather than above have developed a theory: that the subterranean tunnels in which the rakghouls gather are not found, but are actually created by the rakghouls themselves.
Careful study of the tunnels has revealed striking similarities in contour and dimension reminiscent of the natural algorithmic optimizations witnessed in the configuration of killik hives of Alderaan and in the formation of blood-ant mounds on Tatooine.
Furthermore, the familiar distribution of spore sacs and unique flora suggest not only an attempt to create an environment conducive to their habitation, but also a robust fungal signature stored within the virus's genetic code. It is the hope of THORN researchers that unlocking the key to the creation of these tunnels will also provide insight into stopping the rakghoul menace for good.