Jack Nicholson Good Genes or Good Docs?

10/28/2013 12:15 AM PDT

Jack Nicholson: Good Genes or Good Docs?

Jack Nicholson's looks are "As Good As It Gets."

Here's the then 41-year-old "The Shining" actor at a Hollywood movie premiere in 1978 (left) -- and 35 years later the 76-year-old silver screen stud at a boxing event in Las Vegas earlier this year (right).

The question is...