Facial Features Comparisons of Identical Twins

Are Twins Ever Really Identical?

by Joelle Steele

Trying to match up two people’s faces is not as easy as it seems. It takes a very well-trained eye and a lot of experience to tell for sure whether or not you’re looking at two photos of the same person. It is especially difficult if you’re examining old family photos, where family resemblances can confuse even the family members.

Even monozygotic twins (identical and conjoined twins) that are formed from the same egg are not always completely genetically identical. According to a study published in January 2021 in Nature Genetics, this is a result of genetic mutations that occur in the womb when one or both twins create new strands of DNA that then split into more cells. There can be up to 10 to 15 mutations that occur in the womb shortly after fertilization after the egg split apart. This study included 387 pairs of monozygotic twins, their parents, and their children in order to determine if and how the mutations are passed down through multiple generations.

And some fraternal twins look almost identical. Famous twins like Ashley and Mary Kate Olsen claim that they are fraternal twins, but it is unknown if they have had DNA testing done to confirm this. They look like identical twins, even down to having the almost stereotypical tendency towards one twin having a long face while the other has a more rounded face. The Kutcher twins are obviously fraternal.

In case you don’t see the differences between the twins above, or you don’t believe that identical twins are not truly identical, it has been proven time and again that monozygotic twins have variations in their DNA sequences, their fingerprints are different, their weight and height can differ, their facial features placements can vary, and they can have different idiosyncratic traits such as facial lines, scars, or moles. Most of these differences occur during pregnancy when environmental factors such as nutrition, position in the uterus and position relative to the other twin, etc., impact on the development of the twins and their health as well as their appearance.

The following are some photographs of monozygotic conjoined twins, and if you study them closely, you’ll see the differences between them.

As you can see, even conjoined twins do look different, and those differences are apparent even when they are children. Abigail and Brittany Hensel smile differently and their eyes are different. Mary and Anna Arrita have different shaped faces and their chins vary.

Like the Hensels, the Hilton twins already had a slight difference in face shape as children, and their mouths were very different as well. Parents of twins sometimes can’t tell their own children apart at first, but they quickly perceive the sometimes subtle differences. A friend of mine always said she could spot which one of her twins was which from across a playground.

So why all this fuss about identical and conjoined twins and facial features comparison and analysis? Because two people can look very much alike and still be two different people. That is why so many experts who attempt to authenticate photos misidentify the people so often. But, if you can learn to tell monozygotic twins apart using facial features analysis, you will have no trouble distinguishing between who’s who in most photographs.

This article last updated: 01/16/2022.