Star Trek: 10 Things You Didn’t Know About Dax

10. Dax's Original Makeup

As you probably know, the Trill looked very different when they first appeared in The Next Generation. They had prominent forehead ridges, as opposed to Jadzia's iconic spots. However, the makeup crew for DS9 originally planned for a much more canon-friendly look for Jadzia.

We got to have a look at early test shots of Jadzia with forehead makeup in the special features for the Season 2 DVD. After weeks of experimentation, the crew struggled to settle on a final look for the character, and Farrell explained that the markings would keep reducing with each test, until eventually it just looked like she got hit in the forehead. Eventually, the Paramount executives made the final decision to remove her forehead markings, then went through several variations of spots before deciding on the final look.

No explanation was ever given in canon for why the Trill in Next Gen looked so different, but Terry Farrell theorised in Cinefantastique, Vol 23 #6 that spotted Trills were from the north of their planet, and the ones with forehead ridges were from the south. This actually became the explanation for the two different Romulan appearances in Trek, so it may very well be true, but you'd still have to acknowledge the design change of the symbionts somehow.