Zoo keeper Ross Poulter holds a White's Tree Frog in Edinburgh Zoo's new tropical forest zone on September 9, 2011 in Edinburgh, Scotland. The Brilliant Birds Exhibit which brings together beautiful and rare birds from all over the world is now more colourful and unusual, with the unveiling of the zoo's new tropical forest zone bringing together a collection of vertebrates, invertebrates and amphibians for the very first time. (Photo by Jeff J Mitchell/Getty Images)

Twin baby panthers Remaong and Ferra cling to their basket while being presented to the media at Tierpark Berlin zoo on July 13, 2012 in Berlin, Germany. The two panthers were born in captivity on April 26. (Photo by Sean Gallup)

Meerkats are weighed and measured during the ZSL London Zoo 's annual weigh-in on August 22, 2012 in London, England. The height and mass of every animal in the zoo, of which there are over 16,000, needs to be recorded. The measurements are collated in the Zoological Information Management System, from which zoologists can use the data to compare information on thousands of endangered species. (Photo by Oli Scarff)

Zurab Gurielidze, a director of the Tbilisi Zoo, speaks to the media while standing next to a hippopotamus named Begi at the zoo in Tbilisi, Georgia, September 13, 2015. Tbilisi zoo, which was partly destroyed and some 300 animals escaped or died in the floods that also killed at least 19 people in June, was reopened on Sunday. (Photo by David Mdzinarishvili/Reuters)

Humboldt Penguins swim in their pool as a keeper looks on through a spherical window during the annual stocktake press preview at London Zoo in Regents Park in London Monday, January 4, 2016. A requirement of ZSL London Zoo's license, the annual audit takes keepers a week to complete and all of the information is shared with zoos around the world via the International Species Information System, where it's used to manage the worldwide breeding programmes for endangered animals. (Photo by Alastair Grant/AP Photo)

South Korean students pose for a selfie following a traditional coming-of-age ceremony at Namsan hanok village in Seoul on May 15, 2017. The Coming of Age Day is the day to celebrate and encourage the youth who have reached the age of 20, which is considered the beginning of adulthood. (Photo by Ed Jones/AFP Photo)

In a photo taken on July 6, 2017 soldiers of the Korean People' s Army (KPA) watch a fireworks display as part of celebrations marking the July 4 launch of the Hwasong-14 intercontinental ballistic missile, in Pyongyang Fireworks lit up the sky over Pyongyang' s Juche Tower as North Korea celebrated its launch of intercontinental ballistic missile, a milestone in its decades- long weapons drive. On July 4 – the United States' Independence Day – it launched a Hwasong-14 rocket that analysts and overseas officials said had a range of up to 8,000 kilometres, which would put Alaska and Hawaii within reach. (Photo by Kim Won-Jin/AFP Photo)