I was playing Drengin in TotA, and things were progressing normally, but suddenly on one particular turn my influence spread out of my corner over the whole galaxy and my population and income also shot up. I won a cultural victory before even building my first armed ship. I can post two autosaves if it helps.

There also was an anomaly in this game (which was discolored - a civilization graveyard) that no survey ship could pop, and it had the effect of shutting down auto-survey.