Sloth “Paula” hangs from a branch in her enclosure at the zoo in Halle an der Saale, eastern Germany, on June 14, 2019. The two-toed sloth celebrated her 50th birthday and is, according to the zoo, the oldest sloth of the world. (Photo by Hendrik Schmidt/dpa/AFP Photo)

“The Net thrower”. The fisherman are conducting activities on Situgunung Lake. Photo location: Situgunung lake, Sukabumi, West Java, Indonesia. (Photo and caption by Dody Kusuma/National Geographic Photo Contest)

Elena Chernyshova's vision of Norilsk, Russia, the northernmost city in the world, is a series of surprises by which she extracts otherworldly beauty from ugly realities. Here: 2013. A woman is visible through a narrow passageway between two buildings. Norilsk's urban spaces were designed to shorten distances around large developments and give residents maximum protection from arctic winds. (Photo by Elena Chernyshova)

A Muslim woman wearing a Hijab kicks the water in the Mediterranean Sea as a woman wearing a bikini stands nearby at the beach in Tel Aviv, Israel August 30, 2016. (Photo by Baz Ratner/Reuters)

Mario Huettenhofer, chief of the German company 3D Fab, presents his own face as 3d print during the international fairs FabCon 3.D and Rapid.Tech in Erfurt, Germany, Thursday, May 15, 2014. 130 exhibitors from all over the world present the entire world of 3D printing. The trade fairs are accompanied by specialist programs featuring 80 scientists, practitioners and trend analysts from ten countries, who will explain the latest findings, trends and applications for additive processes in industry and for 3D printing in the private sector to newcomers, experts and consumers alike. (Photo by Jens Meyer/AP Photo)

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)

An officer wipes sweat off the face of a Chinese People's Liberation Army (PLA) honor guard soldier as they rehearse for a welcoming ceremony for New Zealand's Governor-General Sir Jerry Mateparae at the Great Hall of the People in Beijing, Tuesday, July 21, 2015. (Photo by Mark Schiefelbein/AP Photo)

Julian, left, is photographed by his mother with friend Gianluca, right, under water at a public pool in Gelsenkirchen, Germany, on a hot Friday, July 3, 2015. Germany faces a heat wave with temperatures up to 38 degrees Celsius (100 degrees Fahrenheit) at the weekend. (Photo by Martin Meissner/AP Photo)