10 Star Trek Fan Theories That Became Fact
7. The Ancient Ones Were Teased In The Original Series
Ronald D. Moore, the writer of The Next Generation episode The Chase, has stated that he considered, though purposefully did not write it into the script, that the Ancient Humanoids that Starfleet, the Klingons, the Romulans and the Cardassians learn of were in fact the same race of aliens from The Original Series episode The Paradise Syndrome.
In that earlier story, the Preservers were a race who travelled the galaxy, rescuing groups who were facing extinction and brought them to other worlds to help them flourish. To keep them safe, large obelisks were constructed on these planets that acted as deflector shields, aiming asteroids away. One such obelisk was present on the planet Amerind, while another was located on one of the moons of Andor.
Though the Preservers were long gone by the time the planet was discovered by the Enterprise, they were in fact the same progenitors that seeded the galaxy with their DNA millions of years before. This common ancestral DNA was shared by many of the galaxy's most prominent species, suggesting that at least some of their advancement was thanks to genetic memory inherited from this race.