Tony Wu / Sperm whale (Physeter macrocephalus), ten swimming together in gathering of more than 50 individuals. Whales with flatulence and defecating. Sri Lanka.

David Perpinan / Adult Common rock sparrow (Petronia petronia) feeding chicks, Cuenca, Castile-La Mancha, Spain, June.

David Perpinan / Rock sparrow (Petronia petronia) feeding chick outside nest, Spain, June.

Remi Masson / European beaver (Castor fiber) swimming underwater and urinating, River Rhone, Rhone-Alpes, France, June.

Tony Wu / Sperm whales (Physeter macrocephalus) large group gathering together, rubbing together to shed skin, interacting and defecating. Indian Ocean, March.

Vincent Grafhorst / Hippopotamus (Hippopotamus amphibius) bull marking territory by flicking dung, Chobe National Park, Botswana

Hanne & Jens Eriksen / Osprey defecating {Pandion haliaetus} Qalhat, Oman

Steven David Miller / Little red flying fox (Pteropus scapulatus) female and baby, hanging with feet down to defecate. Nitmiluk National Park, Northern Territory, Australia.

Doug Perrine / Spanish dancer nudibranch (Hexabranchus sanguineus) defecating whilst swimming. Gato Island, off Malapascua, Cebu, Philippines.

Eric Baccega / Malachite kingfisher (Alcedo cristata) defecating on stone. Baringo lake, Kenya, February.

Stefan Christmann / Emperor penguin (Aptenodytes forsteri) chick defecating whilst brooding on adult's feet. Atka Bay, Antarctica. August.

Stefan Christmann / Emperor penguin (Aptenodytes forsteri) pair in courtship, one defecating. Atka Bay, Antarctica. May.