“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)

Pedestrians cross a road in Cape Town, South Africa Saturday, March 28, 2020, as South Africa went into a nationwide lockdown for 21 days in an effort to control the spread of the coronavirus. (Photo by Nardus Engelbrecht/AP Photo)

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)

An employee sorts waste at the Wecycler recycling centre in Ebutte Meta district in Lagos, Nigeria July 28, 2016. (Photo by Akintunde Akinleye/Reuters)

People try to catch offerings thrown off the summit of Mount Bromo volcano by Tengger tribe members and local tourists in Probolinggo, East Java province on July 18, 2019, as part of the Yadnya Kasada Festival. During the annual Yadnya Kasada festival, the Tenggerese climb Mount Bromo, an active volcano, and seek the blessing from the main deity by presenting offerings of rice, fruit, livestock and other items. (Photo by Juni Kriswanto/AFP Photo)

Snow blows off the Svalbard Global Seed Vault before being inaugurated at sunrise, Tuesday, February 26, 2008. (Photo by John McConnico/AP Photo)

Beach goers sunbath inside a new large scale interactive art work by artist Gregor Schneider entitled “Bondi Beach” at Sydneys Bondi Beach on September 28, 2007 in Sydney, Australia. (Photo by Sergio Dionisio/Getty Images)