Slate gets to the bottom of the backpack question: One strap or two?

We may never know for sure why the dinosaurs went extinct or what happened to Jimmy Hoffa. But thanks to an exhaustive investigation by the Slate writer Forrest Wickman, we now know when teens started wearing their backpacks with two straps instead of one.

In a two-page article that features pie charts, photos, videos and interviews with former one-strappers, Wickman attempts to get to the bottom of when it became cooler to use two straps instead of one.

The article, deliberately over the top and oh so serious, includes some legitimately fascinating anecdotes, especially for anyone who fretted over whether they should risk future back problems in the name of fashion.

Inspired by the "21 Jump Street" movie, in which the two characters debate the relative coolness of one-strap versus two, Wickman conducted his own research, "speaking with 75 ex-students and students from all over the country, spanning 60 years of high-schoolers — from the class of 1965 to the class of 2026."

Wickman found that students from the class of '94 and earlier almost exclusively one-strapped.  Slowly, things began to change until 2008, at which point everybody double-strapped.

Most writers would then call it a day, thinking their work was done. Not Wickman. Not content with just knowing when double-strapping came into vogue, he sought to discover why. Why!

And his odyssey to find the truth led him to consult movies, speak with medical experts, and even track down the former classmate of a co-worker who, though extremely cool, wore his backpack with two straps way before it went mainstream. This devil-may-care attitude is what's known as the "Tom Ferguson effect."

Like the meaning of life, the question of how one-strapping went out of vogue can never be definitively answered, But with pie charts, interviews and a phone call to Tom Ferguson, Wickman showed that  seeking the truth is its own reward. Our straps off to you, sir.