Bence Mate / Head portrait of Dalmatian pelican (Pelecanus crispus) with pouched bill wide open. Danube Delta, Romania

Ernie Janes / Asiatic wild ass (Equus hemionus) with foal, captive, UK, endangered species

Andrew Walmsley / Mini lop-eared domestic rabbit with one ear up and one ear down, and tongue sticking out, Captive, Christchurch, New Zealand

Michael D. Kern / Zoo Atlanta / Lemur leaf frog (Hylomantis lemur) mating pair, captive, Critically endangered, from Central America

Stephen Dalton / Henkel's leaf tailed gecko (Uroplatus henkeli) licking its eye with its tongue, controlled conditions

Steven Kazlowski / Polar bear (Ursus maritimus) sow plays with her spring cub outside their den in late winter, Alaska