In one shot, the Ariel crew have their insignia on the wrong side of their uniforms.
Lt. Cmdr. Markel has Commander stripes.
In one shot Spock has normal human eyebrows.
The Ariel crew appear to wear the same insignia as the Enterprise. During the original five-year mission, different starships had different insignia.
Kirk: The captain of a ship, no matter his rank, must follow the book.
Spock: A capability, I'm afraid, out of the reach of most humans.
McCoy: You Vulcans are the most impossible, unimaginative...
Kirk: Bones, that's not helping the situation.
Kirk: According to their log they beamed down six weeks ago.
Spock: Five weeks, three days, two hours, and four minutes to be exact, Captain.
Kirk: Careless of me, Mister Spock.
McCoy: Strange you didn't get a voice reply.
Spock: There could be many reasons why we did not.
McCoy: Well, never mind counting them.
McCoy: Thanks. The--the air was running out under there.
Kirk: Were you hurt?
McCoy: No, just surprised. It isn't every day a dinosaur falls on you.
McCoy: My shoes are full of sand.
Spock: Doctor, your lack of scientific interest is amazing.
McCoy: I'll be happy to discuss that with you, Mr. Spock, next time you drop into my medical lab.
Kirk: This seems like random choice.
Spock: Unless, of course, the random choice is the pattern.
McCoy: Spock, do you ever say anything straight out?
Spock: I thought I just did, Doctor.
Kirk: A forcefield. It seems harmless enough.
McCoy: So do the bars of a jail unless you're on the inside.
Kirk: You seem to be getting a response.
Spock: My impression is that... they're laughing at me.
Markel: So far, Mr. Spock, we haven't found anything funny in this.
Spock: Animals in a zoo rarely do.
Kirk: What else do they know about us?
Spock: We are considered simplistic, but in the process of evolving into a higher order.
McCoy: Even Vulcans??
Spock: Yes, even Vulcans.
This title is a popular one - both a Next Generation episode and a Trek novel also use it. Neither one bears any relation to this episode.
Allan Dean Foster's Star Trek Log novelization of this episode added on a second "half" of original material which had the Enterprise seeking out a huge flat transparent alien organism, capable of swallowing suns, for the Lactran's collection.
Author David P. Harmon had previously written "A Piece of the Action" and "The Deadly Years" for the original series.