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

Yva Momatiuk & John Eastcott / Ice climber scaling Skaftafellsjokull Glacier, Skaftafell National Park, Iceland

Yva Momatiuk & John Eastcott / Ice climbers atop Skaftafellsjokull Glacier, Skaftafell National Park, Iceland

Yva Momatiuk & John Eastcott / Ice climber scaling Skaftafellsjokull Glacier, Skaftafell National Park, Iceland

Colin Monteath/ Hedgehog House / Kayakers paddling back to cruise ship Polar Pioneer, Lemaire Channel, Antarctic Peninsula, Antarctica

Pete Oxford / Yellow-tailed Surgeonfish (Prionurus laticlavius) school and snorkeler, Galapagos Islands, Ecuador

Pete Oxford / Yellow-tailed Surgeonfish (Prionurus laticlavius) school and snorkelers, Galapagos Islands, Ecuador

Pete Oxford / Red-footed Booby (Sula sula) flying juvenile being photographed by tourist, Genovesa Island, Galapagos Islands, Ecuador

Pete Oxford / Galapagos Sea Lion (Zalophus wollebaeki) pup and tourist, Galapagos Islands, Ecuador

Pete Oxford / Pacific Green Sea Turtle (Chelonia mydas agassizi) and snorkeler, Galapagos Islands, Ecuador

Pete Oxford / Marine Iguana (Amblyrhynchus cristatus) group photographed by tourist, Fernandina Island, Galapagos Islands, Ecuador

Thomas Marent / African Elephant (Loxodonta africana) crossing dirt road near tourists, Serengeti National Park, Tanzania