A Border Collie competes in the Flyball during The World Dog Games at Acer Arena on October 31, 2009 in Sydney, Australia. (Photo by Brendon Thorne/Getty Images)

Attendees Rosalia Rohwer and Jennifer Salenger dress up as characters from the game “Just Dance” at E3, the world's largest video game industry convention in Los Angeles, California on June 12, 2018. (Photo by Mike Blake/Reuters)

Russian servicemen look on as a Mi-24 helicopter fly overhead during the Open Water competition for pontoon bridge units, as part of the International Army Games 2018, outside Murom, Russia August 3, 2018. (Photo by Maxim Shemetov/Reuters)

A traditional game that earned hollers from the crowd saw a male rider gallop after a young woman, stretching for a kiss. Only a handful of the men managed the risky peck before the young women turned the tables and thundered after the men with whips in hand. (Photo by Amos Chapple/Radio Free Europe/Radio Liberty)

This year’s World Nomad Games, a celebration of nomadic heritage, took place in the Issyk-Kul province of Kyrgyzstan. Eleanor Moseman photographed female competitors who had travelled from all over central Asia and eastern Europe, and explored the difficulties and challenges they face as competitors. (Photo by Eleanor Moseman/The Guardian)

Executive producer Dave Alpert attends the season five premiere of “The Walking Dead” at AMC Universal Citywalk on Thursday, October 2, 2014, in Universal City, Calif. (Photo by John Shearer/Invision for AMC/AP Images)

An environmental activist adjusts his mask while taking part in “The Dead Sea Swim Challenge”, swimming from the Jordanian to Israeli shore, to draw attention to the ecological threats facing the Dead Sea, in Kibbutz Ein Gedi, Israel November 15, 2016. Swimmers from around the world plunged into the salty waters of the Dead Sea on Tuesday to attempt a seven-hour swim across the fabled lake in a bid to draw attention to its environmental degradation. Wearing protective masks and snorkels, 25 swimmers paddled through the muddy water to attempt the 9-mile (15-kilometer) swim from Jordan to Israel. (Photo by Nir Elias/Reuters)