Tropical acrobatics by Adrià López Baucells in Manaus, Brazil. An unidentified South American marsupial, although the characteristic black markings on its face indicate it may be a mouse opossum. These small creatures are nocturnal and feed on bugs, fruit and bird eggs. (Photo by Adrià López Baucells/2019 Royal Society of Biology Photography Competition)

A policeman controls traffic at 42nd Street and 7th Avenue as New York City remains without electricity caused by a blackout that affected the entire city and most of the eastern part of the nation August 15, 2003 in New York, New York. More than 50 million people were affected by the outage, in Toronto, Detroit, Cleveland and New York City. (Photo by Jose Jimenez/Primera Hora/Getty Images)

Aerial view of CRH bullet trains setting out ahead of Spring Festival travel rush on January 31, 2018 in Hefei, Anhui Province of China. About 2.98 billion trips will be made during the 40-day Spring Festival travel rush. China will take multiple measures to ensure a smooth Spring Festival travel rush. (Photo by VCG/VCG via Getty Images)

Snow blows off the Svalbard Global Seed Vault before being inaugurated at sunrise, Tuesday, February 26, 2008. (Photo by John McConnico/AP Photo)

A parishioner of the St. Joseph the Worker Parish in Nairobi's Kangemi slum carries the vestments to be worn by Pope Francis during his visit to Kenya on November 24, 2015 in Kenya. Pope Francis makes his first visit to Kenya on a five day African tour that is scheduled to include Uganda and the Central African Republic. Africa is recognised as being crucial to the future of the Catholic Church with the continent's Catholic numbers growing faster than anywhere else in the world. (Photo by Nichole Sobecki/Getty Images)

A salsa dancer performs in the “Salsodromo” parade, which marks the start of the Fair of Cali, Colombia, December 25, 2015. Picture taken December 25, 2015. (Photo by Jaime Saldarriaga/Reuters)

Thousands flock to Bondi Beach for the traditional expats Christmas Day celebration in Sydney, Australia, 25 December 2014. Expats of all nationalities have been flocking to Bondi Beach for Christmas Day for many years. (Photo by Dean Lewins/EPA)

A colourful sky before sunrise on Whitley Bay beach on December 21, 2015, as December could be the mildest across a large part of England since records began more than 350 years ago, forecasters have said. (Photo by Owen Humphreys/PA Wire)