I believe beauty is timeless and identifiable even by babies. Experiments have been done where babies respond to and gaze at a beautiful face longer than average.
There are standard scientific measurements of facial beauty. But it doesn't take a scientist to understand the appeal of diverse, celebrated beauty seen in the faces of Audrey Hepburn, Marilyn Monroe, Brigette Bardot, Sophia Loren, Kate Moss, Karlie Kloss, Victoria's Secret models, and on and on. Validation of the timelessness of beauty is seen in today's fashion magazines that are bringing back Bardot's look and other famous, vintage looks of the past
The nature-given, genetic gift of beauty is an original work of art. Plastic surgeons work to replicate the real deal. But the standards of genetic beauty can only give the surgeons an example to follow.