A member of an Egungun masquerade group, his identity obscured under his ornate costume in Ouidah, Benin on March 13, 2019. The exclusively male practitioners, found across Yoruba culture, use dance and spinning in the belief that they will summon the spirits of ancestors. (Photo by Massimo Rumi/Barcroft Images)

The sunken ferry Sewol sits on a semi-submersible ship during its salvage operations at the sea off Jindo, South Korea, in this handout picture provided by the Ministry of Oceans and Fisheries and released by Yonhap on March 26, 2017. (Photo by Reuters/Yonhap/The Ministry of Oceans and Fisheries)

The Villarrica Volcano is seen at night in Chile, April 16, 2016. Villarrica is one of Chile's most active volcanoes. Picture taken with long exposure. (Photo by Cristobal Saavedra/Reuters)

A man dressed as Hindu Lord Shiva looks into the mirror as he gets ready to take part in a religious procession on the eve of Janmashtami festival in Amritsar, India, September 4, 2015. The festival, which marks the birth anniversary of Lord Krishna, will be celebrated across India on Saturday. (Photo by Munish Sharma/Reuters)

A visitor holds an Israeli-made rifle during the 8th International Land and Naval Defense system exhibition, in New Delhi, India, on February 6, 2014. (Photo by Anindito Mukherjee/Reuters)

“Kilauea Rules”. The most extreme place we put ours kayakers to paddle till now. Photo location: Big Island, Hawaii. (Photo and caption by Alexandre Socci/National Geographic Photo Contest)

A girl collects drinking water at Dala river outside Yangon, Myanmar March 3, 2016. Some 650 million people, or one in 10 of the world's population, have no access to safe water, putting them at risk of infectious diseases and premature death. Dirty water and poor sanitation can cause severe diarrhoeal diseases in children, killing 900 under-five a day across the world, according to United Nations estimates. (Photo by Soe Zeya Tun/Reuters)

A South China Tiger cub meets public at Guangzhou Zoo on June 22, 2017 in Guangzhou, Guangdong Province of China. Guangzhou Zoo boasts of the successful breeding of South China Tiger cub after 15 years. (Photo by VCG/VCG via Getty Images)