Cyril Ruoso / Tropical frog (Hyperolius sp) trying to climb onto leaf, Bateke Plateau NP, Gabon.

Sven Zacek / Ural owl (Strix uralensis) chick trying to climb an aspen tree with its beak, talons and wings, Southern Estonia. June.

Sven Zacek / Ural owl (Strix uralensis) chick trying to climb an aspen tree with its beak, talons and wings, Southern Estonia. June.

Shattil & Rozinski,Shattil & Rozinski / Black bear (Ursus americanus) cub climbing a fence, Minnesota, USA, May.

Andy Rouse / Coquerel's Sifaka (Propithecus coquereli) climbing tree, Palmarium Reserve, Madagascar

Andy Rouse / Coquerel's Sifakas (Propithecus coquereli) in coastal rainforest, Palmarium Reserve, Madagascar

Jerry Monkman / A man climbs "Top of the Prow" rock on Cathedral Ledge. Echo Lake State Park, White Mountains, in North Conway, New Hampshire, USA. October 2009, Model released

Wild Wonders of Europe / Popp-Ha / Matterhorn (4,478m) at night, long exposure with star trails, viewed from Gornergrat, Switzerland, September 2008, climbers in foreground with headlamps setting off to climb the Matterhorn from Hornli...

Andrew Parkinson / Hikers climb A Chailleach in blizzard, Monadhliath mtns, Highlands, Scotland.

Michio Hoshino / Caribou (Rangifer tarandus) of the Porcupine Herd climb Brooks Range foothills at midnight during migration, Alaska

Mark Moffett / Tokay Gecko (Gecko gecko) foot pads showing scales which enable it to climb vertical surfaces by using an intermolecular force called Van der Walls force, southeast Asia

Mark Moffett / Tokay Gecko (Gecko gecko) foot pads showing scales which enable it to climb vertical surfaces by using an intermolecular force called Van der Walls force, southeast Asia