I know Portland doesn't have any teams likely to inspire this behavior anytime soon, but where did the custom of waving one's index finger (real or foam rubber) in the air and shouting "We're number one!" originate?
Oh, Alan. If only you'd asked me about that other famous one-finger gesture. Did you know that monkeys flip each other the bird using their actual erect penises? Obviously, this wouldn't work for people (unless you find getting cut off in traffic a huge turn-on), but it's good to know.
Unfortunately, the street-cred-pursuing academics who've written so much about the digitus impudicus are nearly silent when it comes to the fabled finger of, um, firstness. Luckily, here at "Dr. Know," we never allow an absence of facts to stop us from making something up. You're welcome.
In your letter, you note that you didn't start seeing the gesture until the late '60s. Perhaps not so coincidentally, this is when the Associated Press college football poll started waiting until after the postseason bowl games to issue its final rankings: For the first time, a bowl-game victory had the potential to vault a team into the top spot. It's easy to imagine such a team's fans popularizing the gesture.
The first giant fake finger, a crude papier-mâché affair, was deployed at a high-school game in 1971 (it's sort of insane that we actually know this), and was first mass-produced—in handy plywood!—in 1978.
Of course, you're quite right that local basketball fans probably won't be employing the digitum triumphali (thanks, Google Translate!) this season, but since at this writing the Blazers are in 10th place, you can still bust out the Chinese hand gesture for "10." That gesture just happens to be crossed fingers—très à propos, don't you think?
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