Visitors look at penguins wearing Santa Claus (in red) and Christmas tree (in green) costumes during a promotional event for Christmas at an amusement park in Yongin, south of Seoul, December 18, 2013. (Photo by Kim Hong-Ji/Reuters)

The Northern Lights glow green in a spectacular light show above a field of trees frozen solid with snow. (Photo by Jaak Sarv/Solent News & Photo Agency)

A green iguana, or American iguana sits on an Aldabra giant tortoise, the largest tortoise of the world, in their enclosure at the zoo park of Lille, northern France, on February 11, 2019. (Photo by Philippe Huguen/AFP Photo)

Ivy on a house in North Queensferry, UK begins to turn from green to red as autumn draws nearer on August 26, 2024. (Photo by South West News Service)

This image is NGC 6543 known as the Cat's Eye Nebula as it appears to the Chandra X-Ray Observatory and Hubble Telescope. A planetary nebula is a phase of stellar evolution that the sun should experience several billion years from now, when it expands to become a red giant and then sheds most of its outer layers, leaving behind a hot core that contracts to form a dense white dwarf star. This image was released October 10, 2012. (Photo by J. Kastner/NASA/CXC/RIT)

A British inspired Transformer, made from original bus parts is displayed in front of Tower Bridge on November 28, 2009 in London, England. Twitter fans voted to see a London “bendy” bus made into a Transformer to celebrate the DVD & Blu-ray release of “Transformers: Revenge of The Fallen”. (Photo by Marco Secchi/Getty Images for Paramount Home Entertainment)

Brain-on-a-chip. Dazzling in green and magenta this image shows the nerve fibres (in green) produced by neural stem cells (in magenta) as they grow on a synthetic gel. Captured by a technique known as confocal microscopy, the image is part of research shedding light on how tinkering with the environment can affect the way in which nerve fibres grow. (Photo by Collin Edington and Iris Lee/Massachusetts Institute of Technology/Wellcome Images)