Mount Etna erupting in 2013, Sicily, Italy (© Wead/Alamy Live News)

A blue tit amongst daffodils in Mid Wales, United Kingdom (© Philip Jones/Alamy)

Llaima Volcano with Araucaria trees in the foreground, Conguillío National Park, Chile (© Fotografías Jorge León Cabello/Getty Images)

Two female lions in the forest surrounding Lake Nakuru, Kenya (© Scott Davis/Tandem Stills + Motion)

Nusa Dua coast with breakwater, Bali, Indonesia (© Dkart/Getty Images)

Mineral-laden water in the Rio Tinto in Minas de Rio Tinto mining area, Huelva province, Andalusia, Spain (© David Santiago Garcia/Getty Images)

Komodo National Park, Labuan Bajo, Flores, Indonesia (© Thrithot/Adobe Stock)

Great blue herons in the Wakodahatchee Wetlands, Delray Beach, Florida, USA (© Marie Hickman/Getty Images)

Aerial image of Mount Logan rising above the clouds in Kluane National Park and Reserve, Yukon, Canada (© Robert Postma/plainpicture)

Foothills of the Diablo Range near San Jose, California, USA (© Jeff Lewis/Tandem Stills + Motion)

Lake Hintersee surrounded by alpine mountains, Berchtesgaden, Bavaria, Germany (© Offset by Shutterstock)

Thor's Well at Cape Perpetua on the Oregon coast, USA (© Cavan Images/Offset by Shutterstock)

The Zugspitze mountain reflecting in Eibsee lake, Bavaria, Germany (© Martin Siepmann/Westend61/Offset by Shutterstock)

Common rhododendrons in Semper Forest Park, Rügen, Germany (© Sandra Bartocha/Minden Pictures)

Lyon astronomical clock, Lyon, France (© kyolshin/Alamy)

Screech owl resting in a tree cavity, Massapequa Preserve, Long Island, New York, USA (© Vicki Jauron, Babylon and Beyond Photography/Getty Images)

Giant panda cub in Bifengxia Panda Base, Sichuan, China (© Suzi Eszterhas/Minden Pictures)

Inisheer, the smallest of the three Aran Islands in Galway Bay, Ireland (© Chris Hill/Minden Pictures)

Aerial view of the 'City of Adelaide' shipwreck with trees growing on it, Magnetic Island, Queensland, Australia (© Amazing Aerial Agency/Offset by Shutterstock)

Sundial on Parnidis Dune, Curonian Spit, Lithuania (© amoklv/Getty Images)

Bluebell flowers carpet the Hallerbos forest floor, Flanders, Belgium (© Jason Langley/plainpicture)

Fort de Joux in the Jura mountains of France (© Ivoha/Alamy)

Satellite image of the Mania River in Madagascar (© NASA Earth Observatory image by Joshua Stevens, using Landsat data from the US Geological Survey)

Humpback whale mother pushes her sleeping calf to surface, Maui, Hawaii, USA (© Ralph Pace/Minden Pictures)

Spring ice along the shore of Lake Winnipeg, Manitoba, Canada (© Mike Grandmaison/Jaynes Gallery/DanitaDelimont.com)

Cradle Mountain-Lake St Clair National Park, Tasmania, Australia (© Paparwin Tanupatarachai/Getty Images)

Mountain hare in Scotland (© SCOTLAND: The Big Picture/Minden Pictures)

Mount Snowdon and the Llanberis Pass from Dinorwic quarry, Snowdonia National Park, North Wales, UK (© Alan Novelli/Alamy)

Reynisdrangar basalt sea stacks, Reynisfjara Beach, Iceland (© Cavan Images/Getty Images)

Ostrich fern in Washington state, USA (© Stephen Matera/Tandem Stills + Motion)

Wayag Island, Raja Ampat, Indonesia (© Amazing Aerial Agency/Offset by Shutterstock)