Doug Allan / Emperor penguin males incubating eggs huddle for warmth at -40 degrees centigrade, winter, Antarctica. Green is excrement on snow. {Aptenodytes forsteri}

Doug Allan / Emperor penguin {Aptenodytes forsteri} males huddle for warmth in minus 40 degrees centigrade while incubating eggs in winter, Antarctica Winter extreme cold survival birds seabirds nesting-behaviour

Wild Wonders of Europe / Munier / Man at Roros market which has been there since 1854, exhibitors and vendors come from a long way off, travelling by horse and sleigh, -35 degrees centigrade, Dovrefjell National Park, Norway, February...

Wild Wonders of Europe / Munier / People walking and travelling by horse and sleigh to Roros market. Started in 1854, exhibitors and vendors come from a long way off, -35 degrees centigrade, Dovrefjell National Park, Norway, February...

Wild Wonders of Europe / Munier / People travelling by horse and sleigh to Roros market. Started in 1854, exhibitors and vendors come from a long way off, -35 degrees centigrade, Dovrefjell National Park, Norway, February 2009

Ashley Cooper / Setting the central heating thermostat at a cooler temperature to save energy.

Roy Mangersnes / Sled dog resting, covered in snow, minus 20 degrees centigrade, West coast of Spitsbergen, Svalbard, Norway, March

Wild Wonders of Europe / Munier / People walking and travelling by horse and sleigh to Roros market, started in 1854. Exhibitors and vendors come from a long way off, -35 degrees centigrade, Dovrefjell National Park, Norway, February...

Wild Wonders of Europe / Munier / Woman with breath showing in cold air (-35 degrees centigrade) at Roros market started in 1854. Exhibitors and vendors come from a long way off, travelling by horse and sleigh, Dovrefjell National Par...

Wild Wonders of Europe / Munier / Man wearing fur hat and coat at Roros market first started in 1854. Exhibitors and vendors come from a long way off, travelling by horse and sleigh, -35 degrees centigrade, Dovrefjell National Park, N...

Wild Wonders of Europe / Munier / Horse with some frozen fur, used to pull sleigh to Roros market, started in 1854, -35 degrees centigrade, Dovrefjell National Park, Norway, February 2009

Wild Wonders of Europe / Munier / Woman at Roros market, started in 1854, exhibitors and vendors come from a long way off, travelling by horse and sleigh, -35 degrees centigrade, Dovrefjell National Park, Norway, February 2009