Remi Bizouard races at the Night of the Jumps freestyle motocross acrobatics at O2 arena on March 16, 2012 in Berlin, Germany. (Photo by Carsten Koall/Getty Images)

Blanka Vlasic of Croatia and Team Europe celebrates a clearance in the women's high jump during the IAAF/VTB Continental Cup at the Stadion Poljud on September 5, 2010 in Split, Croatia. (Photo by Michael Steele/Getty Images)

A Polish Army tank takes part in the NATO Noble Jump exercise on a training range near Swietoszow Zagan, Poland, Thursday, June 18, 2015. (AP Photo/Alik Keplicz)

A man drinks at a "colored" water cooler in a streetcar terminal in Oklahoma City, July 1939. (Photo by Reuters/Library of Congress)

A devotee is carried around town in a vessel as part of rituals during the Swasthani Bratakatha festival at Thecho in Lalitpur, Nepal, February 19, 2016. During the month long festival, devotees recite one chapter of a Hindu tale daily from the 31-chapter sacred Swasthani Brata Katha book that is dedicated to God Madhavnarayan and Goddess Swasthani, alongside various other gods and goddess and the miraculous feats performed by them. (Photo by Navesh Chitrakar/Reuters)

A man in “Red Army” garb hits the pavement during a simulated attack during a re-staging of part of the Long March in Jinggangshan September 14, 2017. The scene brings alive an extraordinary chapter in China's history that established the supremacy of Chairman Mao Zedong and the Communist Party. Deep in the mountains of Jinggangshan in the southeastern province of Jiangxi, a classroom of bank tellers participates in an ideological boot camp that plays into Chinese President Xi Jinping's drive to further consolidate his grip on power. (Photo by Thomas Peter/Reuters)

Long-tailed mayflies (Palingenia longicauda) at Tisza river near Tiszainoka 135km (84 miles) southeast of Budapest, June 23, 2013. Millions of these short-lived mayflies engage in a frantic rush to mate and reproduce before they perish in just a few hours during “Tiszaviragzas” or Tisza blooming season from late spring to early summer every year. (Photo by Laszlo Balogh/Reuters)