As part of a very insightful photo series, Beijing-based photographer Gao Rongguo has intimately documented identical twins to show how time has changed the siblings that were born looking the same. The photographer brilliantly captures these pairs of identical twins who are all over the age of 50, showing how they have grown.

The series astutely shows the differences in the twins by pairing them face-to-face so the viewer can really see the intricacies of their physical characteristics. After viewing the images several times, you start to really notice that even if we are all born the same way, time will treat us all very differently. Check out the impacting photo series, which is really as much a sociological experiment as a significant artistic piece.