WHY WAS DATA'S CAT SPOT REFERRED TO AS MALE UNTIL "GENESIS," WHEN "HE" SUDDENLY BECAME A "SHE"?

The Canon Answer:

Not addressed.

The Reference Answer:

Spot may be a changeling, or the victim of an unfortunate transporter accident.
(The Star Trek Encyclopedia)

The Lowdown/The Non-Canon Answer:

Like O'Brien's rank, this is one of those minor details conveniently forgotten for the sake of the episode, in this case "Genesis," which hinged on Spot's kittens as the key to solving the problem presented by the show.

Sex isn't the only issue; the Star Trek Encyclopedia points out that Spot was a Somali cat in "Data's Day," and a common housecat in all his/her other appearances.

The most reasonable answer isn't as fantastic as a transporter accident or a Changeling infiltrator. It's as simple as this: there was more than one Spot. Data, like most of us when we were younger, must've learned to take care of pets through trial and error:

"Second officer's log, supplemental. I learned today that Terran felines differ from Circassian cats in that their heads can NOT be rotated 360 degrees. Reminder to acquire new pet tomorrow morning."

"Second officer's log, supplemental. Must recalibrate sensors on the doors of my quarters to sense the presence of a small animal in the doorway. Reminder to acquire new cat tomorrow morning."

"Second officer's log, supplemental. Feline supplement #46 was...less than satisfactory. Reminder to acquire new pet tomorrow morning, and file report on Andorian salmon's toxicity to small Earth animals."

"Second officer's log, supplemental. Never, never leave Spot alone with Wesley Crusher. Reminder to acquire new pet tomorrow morning..."

You get the picture. By the way, the hypothetical scenario above does not reflect my own personal view towards animals; I love cats.

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