Alex Hyde / Lichen (Parmelia saxatilis) interspersed with orange patches of a Green alga (Trentepohlia sp.) that gets its unusual colouration from the haematochrome (-carotene) it contains. Found growing on a gr...

Neil Aldridge / African scops owl (Otus senegalensis) roosting in shady tree, Kruger National Park, South Africa.

Juergen Freund / 'Be Crocwise' crocodile warning sign, at Shady Camp. Northern Territory, Australia.

Ben Cranke / Jaguar (Panthera onca) resting on a shady river bank, Mato Grosso, Pantanal, Brazil. August.

Ben Cranke / Jaguar (Panthera onca) resting on a shady river bank, Mato Grosso, Pantanal, Brazil. August.

Bryan and Cherry Alexander / Adelie penguin (Pygoscelis adeliae) with shadow on ice floe. Ross Sea, Antarctica.

Peter Cairns / Mallard (Anas platyrhynchos) drake silhouetted on ice, Scotland, UK, February.

Kirkendall-Spring / Fence line at the Buffalo Ranch, Lamar Valley, Yellowstone National Park, Wyoming, USA, January 2014.

Kirkendall-Spring / Fence with shadows on snow, Buffalo Ranch, Lamar Valley, Yellowstone National Park, Wyoming, USA, January 2014.

Guy Edwardes / 2020VISION / Beech (Fagus sylvatica) woodland in spring, Bolderwood, New Forest National Park, Hampshire, England, UK, May.

Michel Roggo / Leaf floating in Clearwater river, outside Clearwater cave. Tributary of the Sungai Melinau river, Gunung Mulu National Park, Sarawak, Borneo, Malyasia, March 2012. Taken for the Freshwater Project.

Michel Roggo / Sungai Melinau Paku river, Gunung Mulu National Park, Sarawak, Borneo, Malyasia, March 2013. Taken for the Freshwater Project.