A Polisario fighter sits on a rock at a forward base on the outskirts of Tifariti, Western Sahara, September 9, 2016. At a rocky outpost in Western Sahara, a new generation of soldiers who have never known war are mobilising as tensions resurface in one of Africa's oldest disputes after a quarter century of uneasy peace. (Photo by Zohra Bensemra/Reuters)

A sculpture made by activists on Lambeth bridge during the Extinction Rebellion protest in London, England on October 7, 2019. (Photo by Henry Nicholls/Reuters)

People look at a black bear at the Chengdu zoo amid the coronavirus outbreak on March 26, 2020 in Chengdu, Sichuan Province of China. (Photo by Wang Lei/China News Service via Getty Images)

A mahout washes an elephant in the river in Pinnawala, some 95 kms from the capital Colombo on April 15, 2020. (Photo by Ishara S. Kodikara/AFP Photo)

A girl wears a mask to help protect herself from the new coronavirus jogs as the sun sets over the Mediterranean Sea coastline, in Beirut, Lebanon, Tuesday, April 14, 2020. (Photo by Hassan Ammar/AP Photo)

Syrian refugee and Olympic swimmer Yusra Mardini is pictured during a training session in a pool at the Olympic park in Berlin, Germany on April 26, 2018. (Photo by Fabrizio Bensch/Reuters)

Iraqi firefighters try to stop the fire of burning oil wells in Kirkuk, northern Iraq, 02 June 2016. Two Khabbaz oil field wells in Kirkuk Province, northern Iraq, exploded by suspected insurgents, a security official said. (Photo by EPA/Stringer)

A rickshaw puller transports passengers through a water-logged street after heavy rain in Kolkata, India on June 26, 2018. (Photo by Rupak De Chowdhuri/Reuters)