Tube passengers take a selfie next to a London underground roundel designed for the launching of the Night Tubes on display at Oxford Circus underground station in London, Britain, 19 August 2016. The long delayed Night Tubes service launched on 19 August. The 24-hour service will operate on Fridays and Saturdays. (Photo by Hannah Mckay/EPA)

Sebastian Vettel of Germany and Red Bull Racing tries his hand at sheep shearing as he visits a local farm during previews to the Australian Formula One Grand Prix on March 23, 2011 in Melbourne, Australia.

Ngorongoro Crater (Tanzania). At 610m deep and 260 sq km, this is the largest unflooded caldera in the world. A blue-green vision from above it's a haven for engangered wildlife and Maasai livestock. The crater was formed three million years ago when a giant volcano, which could have been as high as Kilimanjaro, exploded and collapsed. The caldera formed the concentric fractures in the crust cracked down to a magma reservoir deep underground. (Photo by John Bryant/Getty Images)

Georgian men take a break from selling fruit and vegetable at a street market in Tbilisi, Georgia, Wednesday, July 20, 2016. (Photo by Shakh Aivazov/AP Photo)

Two traditional folk dancers performing in Teheran, Iran. (Photo by Keystone Features/Getty Images). 25th January 1961

Jimmy Arnold, an overweight boy from Rochester, bites into a cake. (Photo by Reg Birkett/Keystone/Getty Images). 14th April 1951

Vocalist Laila Skovmand, a musician with Danish company Between Music, plays underwater in a tank during a rehearsal ahead of their UK premiere concert Aquasonic at the Tramway in Glasgow on Ocrober 25, 2017. (Photo by Robert Perry/PA Images)

Commuters interact with an elephant as he rests in a public road ahead of the annual Perahera festival of the historic Gangaramaya Temple in Colombo on February 18, 2019. Some 50 elephants, most of them from the central area of Kandy along with thousands of traditional drummers, dancers, and monks have gathered in the Sri Lankan capital to participate in the city's biggest two-day annual Buddhist Navam procession, scheduled for February 18-19. (Photo by Ishara S. Kodikara/AFP Photo)