Steven Tyler has been rock and rollin' for over 40 years.
Here's the 28-year-old Aerosmith lead singer back in 1976 (left) -- and 36 years later, the 63-year-old in L.A. on Thursday (right).
American idol, indeed.
Good Genes or Good Docs?
3/4/2012 3:30 AM PST BY Johnny Lopez
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