The love padlocks, called cadenas d’amour, multiplied until there were thousands of love tokens on the bridge, each engraved with a message of love. (Photo by Charles Platiau/Reuters)

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)

People look at a tanker after it fell into a caved-in area on a road in Xi'an, Shaanxi province, July 27, 2013. No casualty was reported in the accident, according to local media. (Photo by Reuters/Stringer)

This undated handout picture made available on February 3, 2016 and provided by Russia's punk band Рussy Riot shows Рussy Riot frontwoman Nadezhda Tolokonnikova performing in the band's new music video titled “Chaika” in Moscow. Russian punk band Рussy Riot, which became a symbol of resistance for a church performance slamming President Vladimir Putin, released a new protest song on February 3 mocking a senior official for alleged corruption. Titled “Chaika”, the satirical song and accompanying video take aim at prosecutor general Yury Chaika, whose two sons have been accused of using their father's position to accrue large fortunes. (Photo by Andrey Noskov/AFP Photo/Russian Punk Band Рussy Riot)

This picture taken on January 1, 2014 shows giant panda “Li Li” sleeping on a tree in Hangzhou Wild Animal World in Hangzhou, east China's Zhejiang province. Giant pandas, notorious for their low s*x drive, are among the world's most endangered animals. Fewer than 1,600 pandas remain in the wild, mainly in China's Sichuan province, with a further 300 in captivity around the world. (Photo by AFP Photo)

Amateur honorable mention | Common raven at Banff National Park in Alberta, Canada. (Photo by Colleen Gara/Audubon Photography Awards)

In this photo provided by Mickey Nuttall, members of an international team of skydivers join hands, flying head-down to build their world record skydiving formation, Friday, July 31, 2015, over Ottawa, Ill. (Photo by Jason Peters via AP Photo)

A supercell thunderstorm develops, May 8, 2017 in Elbert County outside of Limon, Colorado. With funding from the National Science Foundation and other government grants, scientists and meteorologists from the Center for Severe Weather Research try to get close to supercell storms and tornadoes trying to better understand tornado structure and strength, how low-level winds affect and damage buildings, and to learn more about tornado formation and prediction. (Photo by Drew Angerer/Getty Images)