Danny Green / Polar bear (Ursus maritimus) walking across ice, snow covered mountain in background. Svalbard, Norway, April 2018.

Danny Green / Polar bear (Ursus maritimus) male female pair looking upwards, snow covered hills in background. Svalbard, Norway, April 2018.

David Pattyn / Landscape of Hills at the Melnik earth pyramids at sunrise, Foothills of Pirin Mountains, South West Bulgaria, April

Jeff Foott / Fremont Cottonwood (Populus fremontii) trees in autumn, Bentonite Hills, Capitol Reef National Park, Utah

Paul Souders/ Worldfoto / Forested hills in mist, Ngong Hills, Kenya

Chien Lee / Asian Brown Tortoise (Manouria emys) male in rainforest, Tawau Hills Park, Sabah, Malaysia

Paul Bertner / Forest-covered hills and river, Taironaka Lodge, Colombia

John Waters / Panning shot of farmland along southern face of the Mendip Hills, Somerset, England, UK, August 2014

Tim Fitzharris / Arch and Milky Way, Alabama Hills, Sierra Nevada, California

SCOTLAND: The Big Picture / View across Sound of Taransay to North Harris hills in stormy weather , West Harris, Outer Hebrides, Scotland, UK, September 2014.

Floris van Breugel / Beavertail cactus (Opuntia basilaris) in otherwise stark desert, Alabama Hills, Owen's Valley, California, USA May

Wim van den Heever / African elephant (Loxodonta africana) bull 'One Ton' with massive tusks at dusk, with another behind. Chyulu Hills, Kenya.