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 young oriental small-clawed otter at the zoo in Neumuenster, Germany, March 5, 2014. The six young otters (one male, five female) were born on December 7, 2013. (Photo by Maja Hitij/EPA)

Legend by Damien Hirst in the gardens of Chatsworth House on September 9, 2011 in Chatsworth, England. The never before seen work by Hirst is part of the Beyond Limits exhibition of modern and contemporary sculpture displayed in the gardens of Chatsworth by Sotherby's between 9th September to 30th October 2011. (Photo by Christopher Furlong/Getty Images)

Opposition protesters take to the streets of Moscow. Mass meeting in Bolotnaya Square on December 10, 2011 in Moscow, Russia.

Photo by: Stas Sedov and Dmitry Chistoprudov; Source: AirPano

Performers wait for delegations to arrive for traditional nomadic Naadam festival performance during the Asia-Europe Meeting (ASEM) summit just outside Ulaanbaatar, Mongolia, July 15, 2016. (Photo by Damir Sagolj/Reuters)

These tiny insects are so well camouflaged it is nearly impossible to make out their cleverly disguised forms. Canadian photographer and adventurer Paul Bertner attempted to catch the bugs in their natural habitats as part of a hide-and-seek game to show biodiversity in nature. Here: Stick insects. (Photo by Paul Bertner/Caters News)

A jockey drives a buffalo in the annual water buffalo race, part of a week-long festival in homage to the animals and in celebration of the rice harvest in Chonburi, Thailand on April 1, 2016. (Photo by Vichaya Pop/Barcroft Media)

Japanese artist Megumi Igarashi, known as Rokudenashiko, holds her artwork after a news conference following a court appearance in Tokyo April 15, 2015. A Japanese artist on trial for obscenity after making figurines and a kayak modeled on her v*gina said on Wednesday that there was nothing wrong with her artwork and her arrest merely showed how far Japan remains behind the west. Words in the artwork read “Centre. 3D scan”. (Photo by Toru Hanai/Reuters)