Wrestling at the tournament, Naadam Festival, Ulaan Baatar (Ulan Bator), Mongolia, Asia

Hippos fighting, Hippopotamus amphibius, in Kruger National Park, Mpumalanga, South Africa

Two male red hartebeest (Alcelaphus buselaphus) sparring, Mountain Zebra National Park, South Africa, Africa

Detail of battling demons on Khmer style Wat Mahathat Worawihan temple in Phetchaburi, Thailand, Southeast Asia, Asia

Eurasian river otter (Lutra lutra) eating Greater spotted dogfish (Scyliorhinus stellaris). The otter took only the innards of the dogfish by opening a short section of skin behind the pectoral fin (see images under 'Greater spotted dogfish'). The rest of the fish, still alive, was left on the shore and never retrieved. Perhaps the tough shark skin and battling fish are too much work when other food is plentiful? Hebrides, Scotland

Eurasian river otter (Lutra lutra) having caught Greater spotted dogfish (Scyliorhinus stellaris). The otter took only the innards of the dogfish by opening a short section of skin behind the pectoral fin (see images under 'Greater spotted dogfish'). The rest of the fish, still alive, was left on the shore and never retrieved. Perhaps the tough shark skin and battling fish are too much work when other food is plentiful? Hebrides, Scotland

Polo players battling for the ball, polo horses galloping across the snow, Snow Arena Polo World Cup 2010 polo tournament, Kitzbuehel, Tyrol, Austria, Europe

Amadillo (Dasypodidae), peninsula Valdes, Patagonia, east coast, Atlantic Ozean, Argentina, South America

Polo players battling for the ball, polo horses galloping across the snow, Snow Arena Polo World Cup 2010 polo tournament, Kitzbuehel, Tyrol, Austria, Europe

Moose Sparring