Jami Tarris / Polar Bear (Ursus maritimus) cooling off, Spitsbergen, Svalbard, Norway

Marie Read / Wood Ducks (Aix sponsa), females behave aggressively toward a male (second from right) that is trying to join them on a floating log, autumn, New York, USA, October.

Donald M. Jones / Mallard (Anas platyrhynchos) drake flying, Montana

Anup Shah / Olive Baboon (Papio anubis) curious male investigating camera, Masai Mara, Kenya

Juergen & Christine Sohns / Meerkat (Suricata suricatta) trio on guard, Oudtshoorn, South Africa

Richard Du Toit / Burchell's Zebra (Equus burchellii) trio nuzzling, Itala Game Reserve, South Africa

Cyril Ruoso / Long-tailed Macaque (Macaca fascicularis) on ball on beach, Thailand

Donald M. Jones / Red Squirrel (Tamiasciurus hudsonicus) on pine cone flakes, western Montana

Tui De Roy / Volcan Alcedo Giant Tortoise (Chelonoidis nigra vandenburghi), Alcedo Volcano, Isabela Island, Galapagos Islands, Ecuador

Alfred Trunk/ BIA / Common Merganser (Mergus merganser) mother carrying chick, Upper Austria, Austria

Tui De Roy / Blue-footed Booby (Sula nebouxii) performing foot-lifting courtship display, Seymour Island, Galapagos Islands, Ecuador

Tui De Roy / Blue-footed Booby (Sula nebouxii) performing foot-lifting courtship display, Seymour Island, Galapagos Islands, Ecuador