Transcript for Celebrity Doppelgangers: The Science of Looking Alike
Thanks, guys. Okay, next up on "Heat index." Celebrity donele gangers. Buzzfeed. Faces side by side looking eerily alike. What makes two people look the same and Reena ninan has the science behind the story. Reporter: When Katy Perry and so Yi deschanel and they're the celebrity donele gangers you have to see to believe. Aryanna grapd's smile matching up with a teenage Alyssa Milano and Scarlett Johansson, a dead ringer for a young Christopher Walken. Jennifer Lawrence said she can't see the similarities between her and Helen mirren. That was so random and never expected that. All part of buzzfeed's latest slide show equipped with what they not so scientifically call a slidy thing. Uncannyness. It takes hours and hours to make these posts. Matching them up pixel by pixel. Reporter: Is there scientific proof behind the resemblances. Most people in general have many characteristics that can be similar in terms of proportion and bone structure and even how the face ages over time but there are proportions that stand out and there is a mathematical model. Reporter: I was told I look like a young Freida pinto but who is bragging. For "Good morning America," Reena ninan, ABC news, New York.
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