In Omdurman, the largest city in Sudan, the Qadiriyya Sufi order meets every Friday outside Sheikh Hamed Al Nil mosque, which houses the tomb of their 19th century Sufi leader. (Photo by Ala Kheir, John Burns and Ibrahim Algrefwi/Brownbook)

Competitors in the Big Air challenge at the Proryv-2016 festival of extreme sports in Moscow, Russia on March 27, 2016. (Photo by Xinhua/Rex Features/Shutterstock)

Gianluca Pardelli is something of an expert on markets. For the past two years, he’s travelled across eastern Europe, from Azerbaijan to Uzbekistan, Moldova to Georgia, photographing them. Here: Telavi, Georgia. (Photo by Gianluca Pardelli)

A heat-stressed koala waits as a resident pours water on its back on December 19, 2015 in Adelaide, Australia. Adelaide is experiencing an extreme heatwave, with temperatures reaching over 40 degrees for five consecutive days. (Photo by Morne de Klerk/Getty Images)

Eighty one-year-old Sakon Haba (L) wearing loin cloth walks past a police station after he bathed in ice-cold water at the Teppozu Inari shrine in Tokyo January 11, 2015. According to organizers, about 100 participants took part in the Shinto ceremony to purify their souls and wish for good health in the new year. (Photo by Toru Hanai/Reuters)

Senji Nakajima sleeps with his Love Doll “Saori” at Love Hotel on June 4, 2016 in Nagano, Japan. Senji Nakajima, 61 years old, lives with his life-size “love doll” named “Saori” in his apartment in Tokyo, Japan. Nakajima, married with two children, who lives away from home for work, first started his life with Saori six years ago. (Photo by Taro Karibe/Getty Images)

This undated photo provided by the U.S. Fish and Wildlife Service shows two island foxes in Channel Islands National Park, Calif. Three fox subspecies native to California's Channel Islands were removed from the list of endangered species Thursday, August 11, 2016, in what federal officials have called the fastest recovery of any mammal listed under the Endangered Species Act. (Photo by Chuck Graham/U.S. Fish and Wildlife Service via AP Photo)

Two workers shovel mud from the river as they look for gold on March 25, 2014 in Lampang, Thailand. Thai villagers from Wang Nuea, North of Thailand, look for gold in the river every year during the drought season. They are able to make an average around USD 15 per day, however two years ago they reached USD 200 in one day due to the river level dropping so much. The workers begin to search for gold at 10 AM and work until sunset, often working second jobs in the day in order to survive. (Photo by Borja Sanchez-Trillo/Getty Images)