Suzi Eszterhas / African Elephant (Loxodonta africana) in defensive posture towards safari vehicle, Sabi Sands Private Game Reserve, South Africa

Gary Bell/ Oceanwide / Porcupinefish (Diodon nicthemerus) in defensive posture, Port Phillip Bay, Mornington Peninsula, Victoria, Australia

Agustin Esmoris / Scorpion (Brachistosternus pentheri) in defensive posture, Provincial Reserve Luro Park, Argentina

Agustin Esmoris / Scorpion (Brachistosternus ferrugineus) in defensive posture, Argentina

Yva Momatiuk & John Eastcott / Climber climbing rock, Indian Creek, Utah

Ingo Arndt / Prairie Rattlesnake (Crotalus viridis viridis) in defensive posture, South Dakota

Kevin Schafer / Frozen gas bubbles beneath surface of frozen lake, Abraham Lake, Canadian Rockies, Alberta, Canada

Donald M. Jones / Rocky Mountain Elk (Cervus canadensis nelsoni) bull crossing road near truck, North America

Thomas Marent / Lion-tailed Macaque (Macaca silenus) in threat display, Western Ghats, India

Luciano Candisani / Jacare Caiman (Caiman yacare) waiting for fish to swim through open mouth in wetland, Pantanal, Brazil

Luciano Candisani / Jacare Caiman (Caiman yacare) waiting for fish to swim through open mouth in wetland, Pantanal, Brazil

Luciano Candisani / Jacare Caiman (Caiman yacare)fishing in wetland, Pantanal, Brazil