Masaaki Nagumo controls the Land Walker robot at Sakakibara Kikai Co., Ltd Headquarters on May 12, 2005 in Maebashi, Japan. The two legged robot stands at 3.4 metres high and weighs 1000kg. The Land Walker is available to buy for 36,000,000 yen (approximately US $340,000). Masaaki Nagumo developed Land Walker on the basis of the dream he has had in his childhood that enables a person to go on. (Photo by Koichi Kamoshida/Getty Images)

Miss Langata Prison 2016 Ruth Kamande poses for a photograph as female inmates participate in a fashion parade as part of their Valentine's Day celebration, dubbed “love behind bars” inside the Langata Women Maximum Security Prison in Kenya's capital Nairobi, February 14, 2017. (Photo by Thomas Mukoya/Reuters)

People stop to look at the thousands of so-called “love locks”, or “love padlocks”, that hang from a fence across the Hohenzollernbruecke bridge on September 13, 2011 in Cologne, Germany. Love locks are a growing phenomenon in cities across Europe and are meant by the couples who leave them behind as a symbol of their powerful and undying love for one another. (Photo by Dennis Grombkowski/Getty Images)

A soldier from the African Union (AU) peacekeeping force stands guard at the site where a cargo plane carrying supplies for AU troops crash-landed outside Somalia's capital, on October 13, 2015 at Abirska, some 18 kilometres outside Somalian capital, Mogadishu. The officials said the Egyptian-owned transport plane went down after making several unsuccessful passes over the seafront airport. Two of the six crew members suffered light injuries in the crash, the officials said, but added that the plane and those on board were safe having landed in an area controlled by the Somali government and the African Union's AMISOM force. (Photo by Mohamed Abdiwahab/AFP Photo)

A belly dancer dances on the bar at Georgian restaurant Nanuchka in Tel Aviv, Israel July 15, 2015. Nana Shrier, owner of Nanuchka, shocked Israel's culinary world when she removed all animal-based products from the menu. Nanuchka is part of a growing trend that has transformed Israel's financial center into a haven for meatless cuisine. (Photo by Baz Ratner/Reuters)

National Geographic has created “Air, Land & Sea: the 50 greatest wildlife photographs” exhibition. Here: CT4 Crocodile cave on the Salamat river. Set up with Nathan Williamson last chip rain came while we were with the nomads. (Photo by Michael Nichols/National Geographic)

Two chimpanzees share a piece of watermelon at Taronga Zoo on December 23, 2010 in Sydney, Australia. (Photo by Rick Stevens/Taronga Zoo via Getty Images)