After disease wiped out their main food source, the perokh tree, the sooli underwent what they came to call ‘The Awakening’. It turned out that the leaves they had been feeding on were actually filled with powerful intoxicants that had addled them since the dawn of their kind. Now that they had to turn to other forms of sustenance their minds were free to expand to their full potential, turning a simple herd animal into a cultured people.
The transition period was drawn out as many had to give up what had previously been their valuable beasts of burden, a term which causes great offence to any sooli within earshot and is no longer used by the wise or sensitive.
There are some amongst them who believe that their pre-awakened state was the golden age of the sooli and long for the simpler lives the perokh tree provided for their ancestors.