Pope Francis passes past a portrait of himself as he arrives to meet youths in Santo Tomas University in Manila, Philippines, Sunday, January 18, 2015. Francis is in the Philippines on Sunday, the final full day of a weeklong trip that also took him to Sri Lanka. (Photo by Alessandra Tarantino/AP Photo)

Master of throat singing (or Khoomei) Aikhan Orzhak (L) and model Choigana Kertek, dressed in traditional costume, perform during sunset at the Aldyn Bulak area on the bank of the Yenisei River outside the village of Ust-Elegest in Tuva region, Southern Siberia, Russia, October 7, 2015. The region is inhabited by Tuvans, historically cattle-herding nomads, who nowadays practise two main confessions – Buddhism and Shamanism. (Photo by Ilya Naymushin/Reuters)

A model wears a creation from the Alexandre Herchcovitch winter collection during the Sao Paulo Fashion Week in Sao Paulo, Brazil, Sunday, October 18, 2015. (Photo by Andre Penner/AP Photo)

A worker looks on with his camel as he waits for tourists at the Giza Pyramids on the outskirts of Cairo, Egypt, November 8, 2015. Egypt's Tourism Minister Hesham Zaazou said Cairo regretted the suspension of flights and was doing all it could to secure its airports and tourist sites, adding that he would fly to Sharm al-Sheikh to oversee measures to support tourists there. (Photo by Amr Abdallah Dalsh/Reuters)

An Zi, is squashed amongst other commuters in a subway train on his way to work in Beijing, China, November 12, 2015. An, a movie producer, moved to Dongsanqi village in Changping this year. His commute to work can take about 2 hours, with transportation costs topping 200 yuan a month, or about a fifth of his monthly rent. (Photo by Jason Lee/Reuters)

Giant panda Meng Meng plays on a tree at a Siberian tiger-breeding base in Changchun, China on December 10, 2015. (Photo by Xu Chang/Xinhua Press/Corbis)

A woman looks at a mural by South African artist FAITH 47 which decorates a wall in the village of Erriadh, on the Tunisian island of Djerba, on August 8, 2014, as part of the artistic project “Djerbahood”. Artists from 34 diffrents nationalities were invited by France-based Tunisian artist Mehdi Ben Cheikh to take part in an initiative to turn Djerba's Erriadh district into an “open sky museum”. (Photo by Joel Saget/AFP Photo)

A Ka'apor Indian warrior (L) chases a logger who tried to escape after they captured him during a jungle expedition to search for and expel loggers from the Alto Turiacu Indian territory, near the Centro do Guilherme municipality in the northeast of Maranhao state in the Amazon basin, August 7, 2014. Tired of what they say is a lack of sufficient government assistance in keeping loggers off their land, the Ka'apor Indians, who along with four other tribes are the legal inhabitants and caretakers of the territory, have sent their warriors out to expel all loggers they find and set up monitoring camps in the areas that are being illegally exploited. (Photo by Lunae Parracho/Reuters)