Green turtle swimming over a coral reef, Lady Elliot Island, Queensland (© seanscott/Getty Images)

Cove of Spires in Kenai Fjords National Park, Alaska, USA (© Sekar B/Shutterstock)

Christmas Market in Main Square of Braşov, Romania (© Alpineguide/Alamy)

African elephants in Addo Elephant National Park in South Africa (© Robert Harding/Alamy)

The village of Benasque, Huesca, Spain (© Miscelleneoustock/Alamy)

The village of Benasque, Huesca, Spain (© Miscelleneoustock/Alamy)

Birdhouses hanging in a tree (© Westend61/Getty Images)

Macro shot of NSW Christmas bush (© Michael Leslie/Shutterstock)

Bletchley Park bombe code cracking decryption machine, United Kingdom (© Louis Berk/Alamy)

Sleeping Arctic fox (© Menno Schaefer/Getty Images)

Queen of the Andes plants with the Cordillera Blanca massif in the background, Peru (© Cyril Ruoso/Minden Pictures)

Poinsettia leaf close-up (© Charles Floyd/Alamy)

Gornergrat railway station and the Matterhorn in Zermatt, Switzerland (© coolbiere photograph/Getty Images)

Pine grosbeak (© Peter Lilja/Getty Images)

Pine grosbeak (© Peter Lilja/Getty Images)

Ludwig van Beethoven sculptures and monument at the Münsterplatz, Bonn, Germany (© dpa/Alamy Live News)

The English National Ballet's 2016 production of 'The Nutcracker' at the London Coliseum in London, England (© Robbie Jack/Corbis via Getty Images)

Tre Cime di Lavaredo as seen from the Lavaredo fork, Sexten Dolomites, Italy (© AWL Images/Danita Delimont)

Early morning frost on trees in Mount Siguniang National Park in Sichuan Province, China (© Robert Harding World Imagery/Offset by Shutterstock)

Mountain goat kid in western Montana, USA (© Donald M. Jones/Minden Pictures)

Castlerigg Stone Circle near Keswick, Lake District, Cumbria, United Kingdom (© Alan Copson/plainpicture)

Holiday lights on Cape Neddick Light in York, Maine, USA (© Walter Bibikow/Alamy)

Banded pipefish near Moalboal, Philippines (© Jenna Szerlag/Alamy)

Northern lights and wild reindeer on the tundra in Norway (© Anton Petrus/Getty Images)

Australian Christmas sandman with decorations on Bondi Beach, NSW (© fogaas/iStock/Getty Images Plus)

Families play on the snow-covered slopes at Barnett Demesne Park, Belfast, Northern Ireland (© Stephen Barnes/Alamy)

Nabana no Sato garden at night in Kuwana, Japan (© Zoonar GmbH/Alamy)

Ibón de Plan, a lake in the Pyrenees of Huesca, Aragón, Spain (© Getty Images)

Canada lynx in Montana (© Alan and Sandy Carey/Minden Pictures)

Fireworks during a New Year's Eve celebration in Zaragoza, Spain (© Martina Badini/Shutterstock)

Polar bear in waters off Svalbard, Norway (© Westend61/Getty Images)