Robin Thicke -- Good Genes or Good Docs?

Robin Thicke's good looks don't need any blurring.

Here's a 25-year-old version of the singer/songwriter with long locks in New York City back in 2002 (left) and 16 years later ... the now 41-year-old new father rockin' a faux hawk in Tustin, California earlier this year (right).

No lines here.

The question is ...