A migrant carries his belongings as he arrives at the Beijing railway station to catch a train in Beijing, Friday, February 13, 2015. (Photo by Andy Wong/AP Photo)

Rohingya refugees stand outside of their refugee camp on February 11, 2017 in Medan, North Sumatra, Indonesia. Thousands of Rohingya Muslims have been stuck in limbo at Indonesia's refugee camps as the plight of Myanmar's ethnic minority continues. (Photo by Ulet Ifansasti/Getty Images)

In this February 1, 2017 photo, environmental activist Maruja Inquilla poses for a photo next to a Municipal waste treatment plant with water that flows into Lake Titicaca, in Juliaca, in the Puno region of Peru. “If the frogs could talk they would say, This is killing me”," said Inquilla, who recently showed up at the Puno governor's house carrying plastic bags filled with hundreds of dead frogs in protest. (Photo by Rodrigo Abd/AP Photo)

The Invasion. A quiet street in Macau. Modernization around is quickly changing the city, as documented by Paul Tsui. (Photo by Paul Tsui/National Geographic Travel Photographer of the Year Contest)

A young girl sells balloons by the Yamuna River as devotees carrying idols of the Hindu god Ganesh, the deity of prosperity, immerse the idol on the last day of the ten-day-long Ganesh Chaturthi festival in Delhi, India, September 15, 2016. (Photo by Cathal McNaughton/Reuters)

A woman surrounded by South Korean national flags set up to celebrate the 66th Independence Day on August 15, 2011 in Seoul, South Korea. Korea was liberated from Japan's 35-year colonial rule in 1945. (Photo by Chung Sung-Jun/Getty Images)

Students are seen on a pickup truck at the agricultural road which leads to the capital city of Cairo, Egypt, October 13, 2016. (Photo by Amr Abdallah Dalsh/Reuters)

In this photograph taken on April 28, 2018, Afghan children work at a coal yard on the outskirts of Jalalabad, Afghanistan. (Photo by Noorullah Shirzada/AFP Photo)