A visitor passes behind the sculpture “Puma-Dentist” made with plastic, wax and original heads of a puma and a hind by Austrian artist Deborah Sengl during an exhibition at the art gallery Deschler in Berlin April 15, 2008. (Photo by Fabrizio Bensch/Reuters)

Russian pop art photographer Sergey Chilikov captures a nation liberated from the social oppression of late-era Soviet rule – at parties, in the streets, and bouncing high. His exhibition, Photoprovocations, will be at Photo London, 19-22 May. Here: Yoshkar-Ola, Matrosova Street (1995). (Photo by Sergey Chilikov)

See also: Karma by Do Ho Suh

Members of a teenage girl gang convincing an unwilling recruit to join the gang, circa 1955. (Photo by Vecchio/Three Lions)

Meet Barbie Thomas the incredible armless female body builder who is inspiring America. The 37-year-old lost both her arms during a horrific electrical accident as a toddler – but that hasn't stopped her from pursuing her bodybuilding dream.Barbie says she can do anything an average person can do – except she uses her feet. That includes brushing her teeth, making dinner, taking milk out of the fridge, texting, shopping, putting on makeup and even driving. Photo: Barbie Thomas cooks up meals with her feet. (Photo by Incredible Features/Barcroft Media)

Thousands of species of amphibians are endangered and hundreds have already disappeared, but in recent years, a team of scientists and conservationists have re-discovered some of these “lost” species and uncovered previously unknown varieties. Here: Miniature glass frog. (Photo by Robin Moore)

Clouds gather as walkers pause atop a ridge in Mountain View, California January 7, 2016. (Photo by Noah Berger/Reuters)

In this photo taken Saturday, June 20, 2015, Mahmoud Abdulnabi tries out an oud, an Arabic instrument related to the lute, at his workshop in Baghdad, Iraq. “The oud is different than other musical instruments”, said Abdulnabi, who has crafted ouds played by some of Iraq's best known musicians, many of whom look down from headshots on the walls. “If you feel joyful, it can play your joy. If the circumstances are sad it can play your sorrow and... help to empty whatever is in your chest”. (Photo by Hadi Mizban/AP Photo)