Mark Zuckerberg -- Good Genes Or Good Docs?!

Mark Zuckerberg's looks are something to like and comment on!

Here is a 20-year-old version of the cofounder of Facebook proudly showing off his brains over brawns only 3 months after launching FB outside of Eliot House at Harvard University in Massachusetts (left).

And, 16 years later ... the father of two human daughters with his human wife Priscilla Chan -- who celebrated his 36th Earth years birthday earlier this week -- was photographed showing positive emotions and good eye contact while in Brussels for a business meeting earlier this year (right).

His timeline is updated.

The question is ...