A leopard seal feeds Paul Nicklen a penguin. (Photo by Paul Nicklen/National Geographic). Antarctic Peninsula, 2011

A reef shell lies on a beach as the sun sets on Lady Elliot Island located north-east of the town of Bundaberg in Queensland, Australia, June 10, 2015. UNESCO World Heritage delegates recently snorkelled on Australia’s Great Barrier Reef, thousands of coral reefs, which stretch over 2,000 km off the northeast coast. Surrounded by manta rays, dolphins and reef sharks, their mission was to check the health of the world's largest living ecosystem, which brings in billions of dollars a year in tourism. Some coral has been badly damaged and animal species, including dugong and large green turtles, are threatened. UNESCO will say on Wednesday whether it will place the reef on a list of endangered World Heritage sites, a move the Australian government wants to avoid at all costs, having lobbied hard overseas. Earlier this year, UNESCO said the reef's outlook was “poor”. (Photo by David Gray/Reuters)

Two elderly men smoking pipes of opium on a terrace in Korea. (Photo by Bert Hardy/Picture Post/Getty Images). August 1950

A young boy walks to his school bus on a foggy day in Dubai on March 14, 2024. (Photo by Chris Whiteoak/The National)

A regional train passes fog-covered fields in Wehrheim near Frankfurt, Germany, early Friday, October 7, 2022. (Photo by Michael Probst/AP Photo)

This series of pictures shot by satellite, show the man-made world as astronauts see it. Artist Benjamin Grant uses Google Earth to find the most compelling satellite images of human civilization. The stunning pictures of sprawling metropolises and vast reservoirs are sometimes unidentifiable until zoomed in. In order to find an extraordinary picture in the practically endless supply of satellite data, Benjamin focuses on the themes of current events or environmental issues. Here: Industrial Sector, Tokai, Japan. (Photo by Benjamin Grant/Digital Globe/Caters News)

People run away as a building is toppled during a controlled demolition as part of an urban transformation in Ankara, Turkey, February 3, 2014. (Photo by Serap Doganyigit/Reuters)

A giant storm cloud can be seen in the sky above swimmers near Mollymook Beach, south of Sydney, March 5, 2014. (Photo by David Gray/Reuters)