Jabruson / African forest elephant (Loxodonta africana cyclotis) footprint in drying mud, Romani Bai, Odzala-Kokoua National Park, Democratic Republic of Congo.

Ingo Arndt / Grizzly Bear (Ursus arctos horribilis) front and rear tracks in mud, Lake Clark National Park, Alaska

Rolf Nussbaumer / Checkered garter snake {Thamnophis m marcianus} on dry cracked mud, Texas, USA.

Mitsuaki Iwago / African Lion (Panthera leo) pride on cracked mud in dry season, Serengeti National Park, Tanzania

Jack Dykinga / Cracked mud patterns across the valley floor. This mud came from a mudslide and boulders and vegetation were locked into place by the river of mud. Bandwater, Death Valley National Park, Mojave Dese...

Ashley Cooper / Dried up river bed in the Anti Atlas mountains of Morocco, North Africa. April 2012. In recent years, rainfall totals have reduced by around 75% as a result of climate change.

Ashley Cooper / Dried up river bed in the Anti Atlas mountains of Morocco, North Africa. April 2012. In recent years, rainfall totals have reduced by around 75% as a result of climate change.

Ashley Cooper / Mud cracks at Thirlmere reservoir in the Lake District during severe drought, England, UK. July 2010.

Kerstin Hinze / Yellow-bellied toad (Bombina variegata), adult, on dried soil with mud cracks, Weser Hills, Lower Saxony, Germany. August.

Yva Momatiuk & John Eastcott / Cracked mud and bones in seasonal stream bed, Los Glaciares National Park, Patagonia, Argentina

Nick Hawkins / Tracks of Baird's tapir (Tapirus bairdii) cross the cracked mud of a highland peat bog. Talamanca Range, Talamanca Range-La Amistad Reserves / La Amistad National Park UNESCO Natural World Heritage Si...

Steve Gettle / Dry lagoon, Floreana Island, Galapagos Islands, Ecuador