Photographer Martin Schoeller examines the visual nuances of twins. Schoeller was born in Munich, Germany in 1968, studied photography at Lette Verein in Berlin and lives in New York. (Photo by Martin Schoeller)

A couple passes the sculpture “Transformer” by Chinese artist Bi Heng during snowfall in Kassel, central Germany, Tuesday March 12, 2013. Frankfurt airport closed, a quarter of flights out of Paris were canceled, Belgium suffered record traffic jams and high-speed trains were stuck in stations – all because of a sudden dump of oddly late snowfall on Western Europe. Less prepared for the kind of heavy snow that regularly hits northern and eastern neighbors, France, Britain and Belgium struggled Tuesday to keep moving amid the frosty, blustery conditions. (Photo by Uwe Zucchi/AP Photo/Dpa)

A tear rolls down the cheek of Karima el-Mahroug, also known as Ruby, a Moroccan woman at the center of ex-Premier Silvio Berlusconi's s*x-for-hire trial, as she reads a statement to reporters during a protest outside the court house, in Milan, Italy, Thursday, April 4, 2013. The Moroccan woman at the center of ex-Premier Silvio Berlusconi's s*x-for-hire trial has denounced what she says is psychological warfare being waged against her by Italian prosecutors. Ruby, read out a lengthy statement Thursday to a gaggle of reporters in front of Milan's courthouse denying she was a prostitute and insisting that prosecutors hear her side of the story. (Photo by Luca Bruno/AP Photo)

FaceResearch.org, a site run by two psychologists at the University of Aberdeen in Scotland, features software that can average together faces from thousands of photos. These images purportedly show the average face of women from 40 different nationalities.

Catherine, Duchess of Cambridge speaks to soldiers as she arrives at Calgary Airport on July 7, 2011 in Calgary, Canada. (Photo by Chris Jackson/Getty Images)

Models pose backstage ahead of the Review of Australian Fashion Week show as part of Mercedes Benz Fashion Festival Sydney 2011 at Sydney Town Hall on August 24, 2011 in Sydney, Australia. (Photo by Lisa Maree Williams/Getty Images)

A model showcases designs by Twenty Seven Names in a photograph as part of New Zealand Fashion Week 2011 at a Newton Gallery on August 30, 2011 in Auckland, New Zealand. (Photo by Sandra Mu/Getty Images)

Musicians from the West Australian Symphony Orchestra perform a “Symphony in the Sea” at North Cottesloe Beach on December 2, 2008 in Perth, Australia. (Photo by Paul Kane/Getty Images)