Ariana Richards -- Good Genes or Good Docs?

Ariana Richards' good looks are truly out of this world!

Here's a 15-year-old version of the "Jurassic Park" star at an award show back in 1994 (left) and 24 years later ... the now 38-year-old actress was seen looking fossilized at the premiere for "Jurassic World: Fallen Kingdom" in L.A. last week (right)!

She's clearly not going extinct.

The question is ...