A worker polishes an Oscar statuette at R.S. Owens & Company during a media demonstration February 9, 2012 in Chicago, Illinois. (Photo by Scott Olson/Getty Images)

Leopard seal chasing a Gentoo penguin in Antarctica. This image wins the gold prize in the behaviour – mammals category, and the grand prize of World Nature Photographer of the Year. (Photo by Amos Nachoum/World Nature Photography Awards)

Coast and marine winner: Storm Gull (Lesser black-backed gull), New Haven, East Sussex. (Photo by Craig Denford/British Wildlife Photography Awards)

Spectators dressed as leprechauns attend St Patrick's Day parade in Dublin on March 17, 2014. (Photo by Peter Muhly/AFP Photo)

First prize. Taken over Bali Barat National Park, Denpasar, Bali. Made with a GoPro Hero 2 camera. (Photo by Capungaero)

“The power of nature”. Magma, ash and gas erupt from Mount Etna in December 2015, rising to a height of several kilometres. Winner: Nature. (Photo by Giuseppe Mario Famiani/SIPA Contest)

Dancer Chachi Gonzalez arrives at Nickelodeon's 2016 Kids' Choice Awards in Inglewood, California March 12, 2016. (Photo by Mario Anzuoni/Reuters)

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)