Bruno D'Amicis / Red fox (Vulpes vulpes) walking along fallen trunk of old Beech (Fagus sylvatica) tree, Coppo del Principe old-growth beech forest in autumn. Abruzzo, Lazio and Molise National Park / Parco Nazionale...

Luke Massey / Giant otter (Pteronura brasiliensis) resting on a fallen tree in the Rio Cuiaba, Brazil

Theo Bosboom / Underwater view of autumn leaves stuck behind a fallen tree, Leuvenumse beek, the Netherlands.

Nick Upton / Eurasian beaver (Castor fiber) at night, chewing bark and climbing along a felled tree, Devon Wildlife TrustÕs Devon Beaver Project enclosure, Devon, England, UK, March.

Jack Dykinga / Douglas firs (Pseudotsuga menziesii) in 'Wall Street' Canyon. Bryce Canyon National Park, Utah, USA, October.

Jack Dykinga / Fallen Quaking aspen (Populus tremuloides) leaves on wood, autumn, Dixie National Forest, Utah, USA, October.

Sandra Bartocha / European beech tree (Fagus sylvatica). in woodland, Serrahn, Muritz-National Park, World Natural Heritage site, Germany, Europe. October 2015.

Sandra Bartocha / Sun rays shining through European beech woodland (Fagus sylvatica). Serrahn, Muritz-National Park, World Natural Heritage site, Germany, Europe. November 2015.

Neil Aldridge / Vervet monkey (Chlorocebus pygerythrus) yawning while sitting on a fallen tree in forests, Limpopo River, Kruger National Park, South Africa.

Neil Aldridge / Steenbok (Raphicerus campestris) female standing framed by a fallen tree, Mapungubwe National Park, Limpopo Province, South Africa.

Wim van den Heever / Lioness (Panthera leo) on fallen tree at sunset, Okavango Delta Botswana

Juan Carlos Munoz / Ferns growing near fallen tree in Chestnut forest, Onati, Gipuzkoa, Basque Country, Spain, Europe