A lioness drinks after being fed by senior keeper Glynn Hennessy at ZSL London Zoo on August 10, 2016 in London, England. Today marks World Lion Day which highlights the first global campaign to celebrate the importance and plight of lions worldwide. (Photo by Carl Court/Getty Images)

A villa privately built on the rooftop of a residential building in downtown Beijing has prompted complaints from neighbours living below. Professor Zhang, the villa owner, has been instructed to tear down the illegal building, according to the property managers. (Photo by Mark Ralston/AFP Photo)

A tourist reacts as an elephant sprays her with water in celebration of the Songkran water festival in Thailand's Ayutthaya province, April 9, 2014. Songkran, the most celebrated festival of the year, marks the start of Thailand's traditional New Year. (Photo by Chaiwat Subprasom/Reuters)

Russian Police academy female cadets march during a rehearsal for the Victory Day military parade at Dvortsovaya (Palace) Square in St Petersburg, Russia, Wednesday, May 7, 2014. Victory Day, marking the defeat of Nazi Germany, is Russia's most important secular holiday celebrated on May 9. (Photo by Dmitry Lovetsky/AP Photo)

A policewoman uses her mobile phone as navy honor guards stand near of a World War Two memorial during celebrations to mark Victory Day in the Black Sea port of Odessa May 9, 2014. Ukraine celebrates the 1945 victory over Nazi Germany during World War Two on May 9. (Photo by Gleb Garanich/Reuters)

Armed Karo herdsman just back from protecting their cattle herds come down to the river to wash decorative clay markings off their bodies at the end of the day in the Omo Valley, South West Ethiopia. Dus, Omo Valley, Ethiopia, January 2008. (Photo by Brent Stirton/Discovery Communications)

A model prepares backstage ahead of the David Jones Autumn Winter 2017 Collections Launch at St Mary's Cathedral Precinct on February 1, 2017 in Sydney, Australia. (Photo by Mark Nolan/Getty Images for David Jones)

Servicemen of the Belarussian Interior Ministry's special forces unit perform during Maslenitsa celebrations, a pagan holiday marking the end of winter celebrated with pancake eating and shows of strength, at their base in Minsk, Belarus February 19, 2017. (Photo by Vasily Fedosenko/Reuters)