As DS9 progressed and the writers decided where to go with Odo's people, they retconned a lot to make the Founders seem almost impossible to identify. But going by earlier seasons, there are some pretty simple ways one could've identified a Founder who was in disguise:
- taste test. Odo said he had no sense of taste.
- smell test. Odo also said he had no sense of smell.
- digestive test. Odo said he had no digestive system, and that it was disastrous when he did try to eat and drink. Bring on some Sisko's Creole Kitchen!
- cohesion test. Given that changelings had to regenerate after a certain number of hours, attach something like a "matter cohesion monitor" for people to wear whom the Founders might have wanted to replace.
- Betazoid test. Lwaxana said she couldn't read Odo. Have a group of Betazoids scan the minds/emotions of people in question. (And make it a group, in case 1 Betazoid was replaced.) Also perhaps the reason the Dominion occupied Betazed?
- DNA test. In the episode "A Man Alone," a major plot point was that Odo was considered as a murder suspect because his DNA was in the holosuite where the murder occurred. And presumably this would've reverted to its gelatinous state. Later in the series, this would've made all the blood sampling irrelevant, but the audience was expected to forget about it (all the way back in season 1).
- transporter test. A transporter should be able to identify a subject down to their DNA patterns. Are we supposed to believe the Founders could mimic someone down to their DNA level?
- excretion tests.
Sorry to be gross, but since changelings didn't have some basic humanoid systems (as described above), it seems like perspiration and certain bathroom stinkers would've been quite telling.
But the Founders should've simply replaced Odo, as the easiest strategy of hiding in plain sight. They did it once, but never again. And within all the paranoia being expressed in "Paradise Lost" and similar episodes, the possibility of Odo being replaced is never given a second thought, even though it would've been a valid concern and a sound Dominion strategy.
Other ways to identify a changeling?
- taste test. Odo said he had no sense of taste.
- smell test. Odo also said he had no sense of smell.
- digestive test. Odo said he had no digestive system, and that it was disastrous when he did try to eat and drink. Bring on some Sisko's Creole Kitchen!
- cohesion test. Given that changelings had to regenerate after a certain number of hours, attach something like a "matter cohesion monitor" for people to wear whom the Founders might have wanted to replace.
- Betazoid test. Lwaxana said she couldn't read Odo. Have a group of Betazoids scan the minds/emotions of people in question. (And make it a group, in case 1 Betazoid was replaced.) Also perhaps the reason the Dominion occupied Betazed?
- DNA test. In the episode "A Man Alone," a major plot point was that Odo was considered as a murder suspect because his DNA was in the holosuite where the murder occurred. And presumably this would've reverted to its gelatinous state. Later in the series, this would've made all the blood sampling irrelevant, but the audience was expected to forget about it (all the way back in season 1).
- transporter test. A transporter should be able to identify a subject down to their DNA patterns. Are we supposed to believe the Founders could mimic someone down to their DNA level?
- excretion tests.
Sorry to be gross, but since changelings didn't have some basic humanoid systems (as described above), it seems like perspiration and certain bathroom stinkers would've been quite telling.But the Founders should've simply replaced Odo, as the easiest strategy of hiding in plain sight. They did it once, but never again. And within all the paranoia being expressed in "Paradise Lost" and similar episodes, the possibility of Odo being replaced is never given a second thought, even though it would've been a valid concern and a sound Dominion strategy.
Other ways to identify a changeling?
