In the Ancient's Monologue 1, the speaker describes the progress of her species. After thousand of years of expanding, (I believe this includes all ages from Stone to Galactic), the Ancients recognized that they could travel no farther. What if the Ancients never discovered subspace or if no suitable jump nodes existed? What if the Terrans after thousands of years of progress found that they could never escape Sol. Trapped within our local systems, knowing the limits has been reached might change everything. I think there's a subtle message that suggests that once any species reach their maximum capacity, chaos will ensure. Would that suggest the self destruction of those left on Sol?