In this September 10, 1977, file photo, from left, Hua Guofeng, Chinese Communist Party (CCP) chairman and Mao Zedong's immediate successor; Ye Jianying, CCP vice chairman and future ceremonial head of state; Deng Xiaoping, no formal titles at the time but soon to emerge as paramount leader during the reform era; Li Xiannian, CCP vice chairman and future president; Wang Dongxing, head of the leadership bodyguard unit who helped topple the Gang of Four, view the body of later Chinese leader Mao Zedong in Beijing. (Photo via AP Photo)

A picture made available on 14 July 2016 shows Greyhound dogs racing at the Wentworth Park Stadium in Sydney, New South Wales (NSW), Australia, 13 July 2016. Greyhound racing has returned to Sydney's Wentworth Park and other NSW tracks for the first time since the state government announced plans to ban it. NSW Premier Mike Baird announced last week plans to shut down the sport in NSW following a Special Commission of Inquiry report that found “chilling” evidence of systemic animal cruelty within the industry. (Photo by David Moir/EPA)

Tami Varma, right, and her brother Robin, the grandchildren of Devendra Varma, a scholar of English gothic tales and an expert in vampire lore, pose in coffins at the Bran Castle, in Bran, Romania, Monday, October 31, 2016. A Canadian brother and sister are passing Halloween night curled up in red velvet coffins in the Transylvanian castle that inspired the Dracula legend, the first time in 70 years anyone has spent the night in the gothic fortress, after they bested 88,000 people who entered a competition hosted by Airbnb to get the chance to dine and sleep at the castle in Romania. A portrait of medieval prince Vlad the Impaler is placed on the wall. (Photo by Vadim Ghirda/AP Photo)

People release floating lanterns during the festival of Yee Peng in the northern capital of Chiang Mai, Thailand November 14, 2016. Yi Peng refers to the full moon day in the second month according to the Lanna lunar calendar (the twelfth month according to the Thai lunar calendar). Swarms of Lanna-style sky lanterns are launched into the air where they resemble large shoals of giant fluorescent jellyfish gracefully floating through the sky. The festival is meant as a time for tham bun, to make merit. Khom loi are made from a thin fabric, such as rice paper, stretched over a bamboo or wire frame, to which a candle or fuel cell is attached. When the fuel cell is lit, the resulting hot air is trapped inside the lantern and creates enough lift for the khom loi to float up into the sky. (Photo by Athit Perawongmetha/Reuters)

A French riot police officer is surrounded by flames, during a demonstration against the controversial labour reforms of the French government in Paris on September 15, 2016. Opponents of France's controversial labour reforms took to the streets on September 15, 2016 for the 14th time in six months in a last-ditch bid to quash the measures that lost the Socialist government crucial support on the left. Scores of flights in and out of France were cancelled as air traffic controllers went on strike to try to force the government to repeal the changes that became law in July. (Photo by Thomas Samson/AFP Photo)

Two boys in the Gorbals area of Glasgow, UK on January 31, 1948. The Gorbals tenements were built quickly and cheaply in the 1840s, providing housing for Glasgow's burgeoning population of industrial workers. Conditions were appalling; overcrowding was standard and sewage and water facilities inadequate. The tenements housed about 40,000 people with up to eight family members sharing a single room, 30 residents sharing a toilet and 40 sharing a tap. By the time this photograph was taken 850 tenements had been demolished since 1920. Redevelopment of the area began in the late 1950s and the tenements were replaced with a modern tower block complex in the sixties. (Photo by Bert Hardy/Getty Images)

The National Geographic Photo Ark is a travelling exhibition of photographer Joel Sartore’s quest to create a photo archive of biodiversity around the world. So far, Sartore has captured studio portraits of more than 6,000 species – a number that he hopes to double. On 1 July, the ark will open at Melbourne zoo – the first time it has been exhibited in the southern hemisphere. More than 50 portraits will be on display, including many of Australian endangered animals being protected by programs at the zoo itself. These captions have been edited from text supplied by Melbourne zoo. Here: Barking owl. (Photo by Joel Sartore/National Geographic Photo Ark/The Guardian)

Picture dated October 23rd, 2018 shows brother and sister Henry (7) and Lily Sales (9) getting in some early practice for the World Puddle Jumping Championships at Wicksteed Park in Kettering, Northants, UK. Organisers have made more puddles than ever before in an attempt to make this year's competition the biggest and best yet. They are also hoping competitors will set a new record for the most people jumping in puddles at the same time. Judges will give scores based on the height of the jump, enthusiasm, distance of splash and stickability (the amount of mud which clings to each competitor). (Photo by Geoff Robinson Photography)