A family of baby brown bears appear to be dancing to Ring a Ring o' Roses as their mother relaxes behind a tree nearby. At just a few months old, two young males and one female gather in a circle, clutch each others' hands and begin to dance to the popular nursery rhyme. It's almost like a scene from a school playground as the bears joyfully play together, tapping their feet and moving around in a circle. (Photo by Valtteri Mulkahainen/Solent News & Photo Agency)

Engine driver Josef Kowatsch (top L) steers a train through the NEAT Gotthard Base Tunnel during a media visit near the town of Erstfeld August 24, 2015. Crossing the Alps, the world's longest train tunnel should become operational at the end of 2016, consisting of two parallel single track tunnels, each of a length of 57 km (35 miles). (Photo by Arnd Wiegmann/Reuters)

Full-time feline photographer Andrew Marttila from Washington, D.C., captured blissful expressions of various cats on catnip, which he used to compile a book, “Cats on Catnip”. The photographer dedicated his time to capturing the euphoric expressions of kitties high on catnip – and the results are absolutely hilarious. (Photo by Andrew Marttila/Caters News Agency)

Russia's President Vladimir Putin and Saudi Arabia's Crown Prince Mohammed bin Salman are seen during the G20 summit in Buenos Aires, Argentina November 30, 2018. G20 powers open two days of summit talks on Friday after a stormy buildup dominated by tensions with Russia and US President Donald Trump's combative stance on trade and climate fears. (Photo by Marcos Brindicci/Reuters)

General view at the Red Bull Music Academy x Mangrove float at Notting Hill Carnival on August 28, 2017 in London, England. The Notting Hill Carnival has taken place since 1966 and now has an attendance of over two million people. (Photo by Tristan Fewings/Getty Images for RedBull)

This photo taken on March 29, 2017 shows a young woman offering shots of liquer at a dance bar in Walking Street in Pattaya. Two hours east of Bangkok, Pattaya's bawdy reputation hails from the Vietnam War era when US GIs partied in their downtime. (Photo by Roberto Schmidt/AFP Photo)

A young evacuee of Japanese ancestry waits with the family baggage before leaving by bus for an assembly center in California, in this April 1942 handout photo. February 19, 2017 marks the 75th anniversary of FDR signing executive order 9066, authorizing the internment of Japanese Americans during World War Two. (Photo by Courtesy Clem Albers/Department of the Interior/War Relocation Authority/National Archives/Reuters)

Yan Zhengming (R), 94, and his wife Zhou Suqing (C), 90, attend their wedding ceremony at their home, on the 70th anniversary of their marriage, in Quxian county of Dazhou, Sichuan province, China, May 15, 2015. The wedding, organized by local charity groups, was a long-time wish of veteran of the World War Two Yan, who married Zhou 70 years ago, but could not afford to have a wedding ceremony, local media reported. (Photo by Reuters/Stringer)