Soldiers from Japan's Ground Self Defense Force come ashore in amphibious assault vehicle as they train alongside U.S. Marines during the bilateral annual Iron Fist military training exercise in Camp Pendleton, California February 26, 2016. (Photo by Mike Blake/Reuters)

Female pilot Anna climbs out the cockpit of Japanese electronics company Suidobashi Heavy Industry's newly unveiled robot “Kuratas” at the Wonder Festival in Chiba, suburban Tokyo on July 29, 2012. The “Kuratas” robot, which will go on sale with a price tag of one million USD, measures four meters in height, weighs four tons and has four wheeled legs that can either be controlled remotely through the 3G network or by a human seated within the cockpit. (Photo by Yoshikazu Tsuno/AFP Photo)

Old Heidelberg, Dog with Pipe, 1905. (Photo by Detroit Publishing Company)

Brazilian graffiti artist Eduardo Kobra (C) puts the final touches to his piece of art in tribute to Brazilian architect Oscar Niemeyer, next to his assistants, at the financial center on Sao Paulo's Avenida Paulista January 22, 2013. Kobra created the 56-metre (61-yard) tall graffiti artwork as a tribute to Niemeyer, one of the 20th century's most influential modernist architects. Niemeyer died in December 2012, aged 104. (Photo by Andre Penner/AP Photo)

Frank A. Rinehart, a commercial photographer in Omaha, Nebraska, was commissioned to photograph the 1898 Indian Congress, part of the Trans-Mississippi International Exposition. More than five hundred Native Americans from thirty-five tribes attended the conference, providing the gifted photographer and artist an opportunity to create a stunning visual document of Native American life and culture at the dawn of the 20th century. Photo: Little Bird, Arapahoe, 1899. (Photo by Frank A. Rinehart)

Thousands gather to rally for marriage equality ahead of a national postal survey on September 10, 2017 in Sydney, Australia. The High Court handed down its decision on Thursday to allow the government's proposed postal ballot survey to go ahead. Ballots with the question “Should the law be changed to allow same-sеx couples to marry?” will be sent to households across Australia on September 12. (Photo by Jonny Weeks/The Guardian)

Actress Liv Tyler, 40, stripped in shots for the Triumph Essence's Autumn/Winter 2017 campaign in November, 2017. The Essence line is Triumph’s premium offering, with this season taking on the theme of “opulent Art Nouveau”, featuring designs in velvet embellished mesh, Leavers lace and silk satin. (Photo by Rankin/The Mega Agency)

Girls practice sit-ups during gymnastics lessons at the Shanghai Yangpu Youth Amateur Athletic School in Shanghai, China, on May 4, 2016. China's sports system has been enormously successful since the country returned to the Olympic fold in 1980, culminating with the host nation topping the medals' table at the 2008 Beijing Olympics. And yet, with the Rio de Janeiro Games less than three months away, the system is beginning to break down due to the shifting demographics of a more prosperous nation. (Photo by Aly Song/Reuters)