A Chinese man wears a mask to protect against pollution as he waits at a red light while commuting to work in heavy smog on December 8, 2015 in Beijing, China. The Beijing government issued a 'red alert' for the first time since new standards were introduced earlier this year as the city and many parts of northern China were shrouded in heavy pollution. Levels of PM 2.5, considered the most hazardous, crossed 400 units in Beijing, lower than last week, but still nearly 20 times the acceptable standard set by the World Health Organization. The governments of more than 190 countries are meeting in Paris to set targets on reducing carbon emissions in an attempt to forge a new global agreement on climate change. (Photo by Kevin Frayer/Getty Images)

A large bull walrus returns to the shores of Prins Karl Forland after diving and feeding on clams. (Photo by Paul Nicklen/National Geographic). Svalbard, Norway, 2011

Patience paid off for the photographer who waited for hours to catch a crocodile on Java, the largest Indonesian island in March 2023. (Photo by Tanto Yensen/Solent News)

A baby orangutan called Barney shows off his dancing at Ragunan Zoo in Jakarta, Indonesia in the first decade of November 2023. (Photo by Syahrul Ramadan/Media Drum Images)

Pictured is the sunset at Stonehenge in Wiltshire on Saturday night, September 24, 2022. (Photo by Nick Bull/pictureexclusive.com)

These little grizzly bear cubs had fun making a real splash when their mum took them for a dip to learn how to fish. Kamchatka, Russia. (Photo by Marco Mattiussi/Solent News & Photo Agency)

Women wait for customers at the fish harbour in Kasimedu Fish market, Chennai, India, on June 26, 2024. (Photo by Riya Mariyam R./Reuters)

Two hippopotamus are fed with pumpkins at the Hanoi Zoo, in Hanoi, Vietnam, 25 October 2018. The zoo has been the home for more than 800 animals of over 90 different species, including three hippopotamus, since it was built in 1976. (Photo by Luong Thai Linh/EPA/EFE)