During the species evolution, they have had many corporeal forms. 10 Billion years prior their people once called themselves "Endless", but political and spiritual differences placed them on different paths. Exiled, they desperately sought redemption. In their hast of scientific advances in the short years following their exile, they left their morality behind. Their physical form started to reflect those changes. In the end, they never would reach their goals of ascension, but rather left alone in the galaxy as a broken shell of their once great selves. The leadership maintained itself over the innumerable years of silence, but when life returned to the galaxy they sought not to explore their once great empire, but to pay penitence for their sins; seeking peace and to build strong ties with their neighbors within the galaxy. To aid the worry in unlock secretes of the Endless. 

 - They are a reserved people, population growth is reflected in their slow growth rate.

 - Utilization of industry is extremely efficient and don't require a large planet population

 - Science is directly proportional to their diplomatic standing with the other factions.

 - Adherent to military advancement and disavowed all aggressive behavior of their past. 

Yay for Endless lore. I support this.