He's part of one of rock's grooviest, funniest trios -- the bedrock bassist of a group that's never changed lineups in more than four decades of guitar-flipping, hoopty-car space shuttle-captaining blues boogie.

Having sold more than 50 million records along the way, he's withstood health issues both scary (a gutshot from a dropped postol) and every day (a recent hip injury suffered while on tour), all while boasting a heaping helping of facial hair that's defined his (and his band's) look. And he's kept up with the times, mastering synthesizers in preparation for a stunning reinvention of their rootsy sound at the dawn of the MTV era.

Think you know who we're talking about? There's only one way to be sure -- click on the button below to find out who this young man grew up to be!

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