Smithsonian National Zoo biologist Leigh Pitsko releases a male lion cub for its swim test in the zoo habitat moat, in Washington May 6, 2014. Four, unnamed ten-week old lion cubs were tested today for their ability to swim and remove themselves from their zoo habitat moat. (Photo by Gary Cameron/Reuters)

Promotional models use their smartphones during their break at the Global Mobile Internet Conference in Beijing May 6, 2014. Mobile Internet industry executives, developers and investors from more than 30 countries took part in the Global Mobile Internet Conference in Beijing, the organiser said. (Photo by Kim Kyung-Hoon/Reuters)

A protester with his face smeared with soot from burning barricades stands in the Musaga neighbourhood of Bujumbura on May 6, 2015. Government and opposition rivals are meeting in Burundi in a bid to end deadly demonstrations against a third term bid by the president, as regional foreign ministers arrived to add pressure. (Photo by Phil Moore/AFP Photo)

Part made cricket bats sit in a box at the Salix Cricket Bat Company in Langley, Britain July 6, 2015. Salix Cricket Bat Company use traditional tools and techniques to make cricket bats by hand. (Photo by Neil Hall/Reuters)

Servicemen of “Kiev 12” military defence battalion react as they take part in a welcoming ceremony in central Ukrainian capital Kiev December 6, 2014. Servicemen of the battalion returned to Kiev after taking part in fighting in eastern Ukraine. (Photo by Gleb Garanich/Reuters)

Buddy Mae Walker (R), 4, looks at herself in the mirror while trying on a child respirator provided by the non-profit TeamRaccoonPDX on October 6, 2020 in Portland, Oregon. We told them their grandparents sent them space suits to keep them safe, Jessica Walker said of the respirators, which the family sought out after police used tear gas near their residential street. (Photo by Nathan Howard/Getty Images)

Artist Sayna Soleimanpour performs a photoshoot in protest against the mistreatment and alienation of Turkish women based on their clothing, during a two-day curfew amid the spread of the coronavirus disease (COVID-19), on a deserted street in Istanbul, Turkey, early December 6, 2020. (Photo by Umit Bektas/Reuters)

Ceremonial skulls La Paz, Bolivia on November 6, 2020. Toads are in Bolivia symbols of the soil and of luck. They complement the Ñatitas, skulls of deceased people that are believed to have special powers. People ask them for different favours. The tradition is related to All Saints´ Day. (Photo by Radoslaw Czajkowski/Rex Features/Shutterstock)