Lucas Bustamante / Humpback whale (Megaptera novaeangliae) fluke above the water as it dives, Machalilla National Park, Manabi, Ecuador.

Anup Shah / African elephant (Loxodonta africana) walking up a gully from the Mara River, wide angle perspective taken with a remote camera. Maasai Mara National Reserve, Kenya.

Tony Wu / Humpback whale (Megaptera novaeangliae) rear view, taken while the whale was staying still and singing. Hunga Channel. Vava'u, Kingdom of Tonga, Pacific Ocean.

MYN / Paul van Hoof / Italian crested newt (Triturus carnifex) male, The Netherlands, April. Meetyourneighbours.net project.

Konrad Wothe / Two Reticualted giraffes (Giraffa camelopardalis reticulata) close up of tails and hind legs, Samburu Game Reserve, Kenya, East Africa, August.

Tony Heald / Yacare caiman (Caiman yacare) abstract view of tail and reflection at sunrise, Pantanal, Brazil

Tony Heald / Yacare caiman (Caiman yacare) basking on river bank, Pantanal, Brazil

Tony Wu / Sperm whale (Physeter macrocephalus) fluke of a female swimming near the surface, Sri Lanka, Indian Ocean.

Lou Coetzer / Pintailed whydah (Vidua macroura) male displaying to female, Masai Mara, Kenya.

Lou Coetzer / Pintailed whydah (Vidua macroura) male displaying to female, Masai Mara, Kenya.

Mark Taylor / Fluffy black kitten, 10 weeks, walking.

Nick Upton / White-fronted goose (Branta albifrons) pair courting, swimming close together with their tails raised in display, on flooded pastureland, Gloucestershire, UK, March.

Roland Seitre / Geoffroy's woolly monkey (Lagothrix cana) captive, occurs in Brazil, Bolivia, and Peru.

Roland Seitre / Gray woolly monkey (Lagothrix cana) climbing, captive, occurs in Brazil, Bolivia, and Peru.

Roland Seitre / Common woolly monkey (Lagothrix lagothricha) hanging upside down from branch using prehensile tail, over water, captive, occurs in Brazil, Columbia, Ecuador, Peru.

Roland Seitre / Black bearded saki (Chiropotes satanas) captive, endemic to Brazil. Critically endangered species.

Nick Upton / Harvest mouse (Micromys minutus) clinging to a Common hogweed (Heracleum sphondylium) flowerhead with its feet and tail after release into the wild, Moulton, Northampton, UK, June.

Nick Upton / Harvest mouse (Micromys minutus) using its gripping tail to aid its descent of a Common hogweed (Heracleum sphondylium) stem after release into the wild, Moulton, Northampton, UK, June.

Nick Upton / Harvest mouse (Micromys minutus) clinging to a Common hogweed (Heracleum sphondylium) flowerhead with its feet and tail after release, Moulton, Northampton, UK, June.

Enrique Lopez-Tapia / Tails on hind wings of Comet moth (Argema mittrei) Captive, endemic to Madagascar.

Alex Hyde / Cirrus uncinus or Mares' Tails cloud formations, Isle of Mull, UK.

Pascal Kobeh / Tail of a Whale shark (Rhincodon typus) in open water, Los Roques, Venezuela. Caribbean.

Pascal Kobeh / Tail of a Humpback whale (Megaptera novaeangliae) under the surface, with barnacles, Reunion Island. Indian Ocean.

Ann & Steve Toon / Two African lion tails (Panthera leo), Kgalagadi Transfrontier Park, Northern Cape, South Africa, February

Markus Varesvuo / Fox (Vulpes vulpes) crossing grassland, Norway, July

Ammonite / Two Sperm whales (Physeter macrocephalus) breathing at the surface before swimming away, Azores, Portugal, July.

Ammonite / Cheetah (Acinonyx jubatus) cub playing with mother's tail, with second cub suckling nearby, Masai Mara, Kenya.

Ammonite / Cheetah (Acinonyx jubatus) cub playing with mother's tail, with second cub suckling nearby, Masai Mara, Kenya.

Ammonite / Two African lionesses (Panthera leo) greeting and playing, with a sub-adult male looking on, Masai Mara, Kenya.

Ammonite / Hippopotamus (Hippopotamus amphibius) dung spreading with tail, footage taken at night using thermal camera technology, Masai Mara, Kenya.

Ammonite / Two juvenile Black-handed / Geoffroy's spider monkeys (Ateles geoffroyi) playing with a Mantled howler monkey (Alouatta palliata) in tree, showing use of prehensile tails, Santa Rosa National Park, Co...

Ammonite / Juvenile Black-handed / Geoffroy's spider monkey (Ateles geoffroyi) playing with a Mantled howler monkey (Alouatta palliata) in tree, Santa Rosa National Park, Costa Rica. Sequence 2/2.

Ammonite / White-throated / White-faced capuchin (Cebus capucinus) hanging from branch using prehensile tail and feeding on berries, Santa Rosa National Park, Costa Rica.

Ammonite / Juvenile White-faced / White-throated capuchin (Cebus capucinus) climbing down tree and jumping onto parent's back, showing use of prehensile tail, Santa Rosa National Park, Costa Rica.

Ammonite / White-faced / White-throated capuchin (Cebus capucinus) climbing down tree, showing use of prehensile tail, Santa Rosa National Park, Costa Rica.

Ammonite / White-faced / White-throated capuchin (Cebus capucinus) climbing down tree, showing use of prehensile tail, Santa Rosa National Park, Costa Rica.

Ammonite / Wide-shot of White-throated / White-faced capuchin (Cebus capucinus) climbing down tree, showing use of prehensile tail, Santa Rosa National Park, Costa Rica.

Chris Mattison / Rattles from tails of two Rattlesnakes (Crotalus sp) from an old (top) and young snake, Arizona, USA.

Paul Harcourt Davies / Common swallowtail (Papilio machaon) close up of wing 'tails' Orvieto, Italy, October.

Will Burrard-Lucas / Genet (Genetta) at night, taken with remote camera. South Luangwa National Park, Zambia.

Gabriel Rojo / Orca (Orcinus orca) tail fluke, Caleta Valdez, Provincial Reserve, Peninsula Valdez, Chubut, Patagonia Argentina

Gabriel Rojo / Orca (Orcinus orca) hunting sea lion pups, Caleta Valdez, Provincial Reserve, Peninsula Valdez, Chubut, Patagonia Argentina

Wim van den Heever / Baby Chacma baboon (Papio hamadryas ursinus) looking over an adult's back, Chobe National Park, Botswana.

Gabriel Rojo / Orca (Orcinus orca) hunting, Punta Norte Provincial Reserve, Peninsula Valdez, Chubut, Patagonia Argentina

Roland Seitre / Wilson's bird-of-paradise (Cicinnurus respublica) rear view, captive. Endemic to Indonesia.

Roland Seitre / Wilson's bird-of-paradise (Cicinnurus respublica) rear view, captive. Endemic to Indonesia.

Michel Roggo / Black caiman (Melanosuchus niger) underwater in the flooded forest of a Rio Negro tributary, Amazon, Brazil.

MYN / Dimitris Poursanidis / Regenerated tail of Moorish Wall Gecko (Tarentola mauritanica) Crete, Greece, March. Meetyourneighbours.net project.

MYN / Dimitris Poursanidis / Regenerated tail of Moorish Wall Gecko (Tarentola mauritanica) Crete, Greece, March. Meetyourneighbours.net project.

Radomir Jakubowski / Chamois (Rupicapra rupicapra) view of tail, Vosges Mountains, France.

Radomir Jakubowski / Alpine ibex (Capra ibex) close up of tail, Bernese Alps, Switzerland, April.

Charlie Summers / The tail of a drake Bufflehead duck (Bucephala albeola) is fanned as it dives in a Bosque del Apache, New Mexico drainage canal.

Bertie Gregory / Grey whale (Eschrichtius robustus) diving with fluke in the air, Vancouver Island, British Columbia, Canada, July.

John Cancalosi / Eastern Chipmunk (Tamias striatus) resting, New York, USA, September.

Bertie Gregory / Grey whale (Eschrichtius robustus) diving at sunset with tail fluke above water, Vancouver Island, British Columbia, Canada, July.

Terry Whittaker / Humpback whale (Megaptera novaeangliae) fluke above water before diving near whale watching boat, Skjalfandi Bay, Iceland, July 2012.

Jeff Vanuga / Tail of horse, Shell, Bighorn Basin, Wyoming, USA, September.

Jeff Vanuga / Tail of horse, Shell, Bighorn Basin, Wyoming, USA, September.

David Tipling / Resplendent Quetzal (Pharomachrus mocinno) male leaving nest, Central Highlands, Costa Rica, March.

David Tipling / Rufous-tailed Hummingbird (Amazilia tzacatl) and Booted racket-tails (Ocreatus underwoodii) around feeder, Ecuador.

David Tipling / Violet-tailed Sylph (Aglaiocercus coelestis) male, Mindo, Ecuador.

Enrique Lopez-Tapia / Bottlenose dolphin (Tursiops truncatus) diving in front of a catamaran in the Walvis Bay Lagoon, Namibia, September 2013.

Michael Durham / Rear view of La Plata / Southern three-banded armadillo (Tolypeutes matacus) Captive.

Ernie Janes / Black headed gull (Chroicocephalus / Larus ridibundus) in flight just above water fishing, Titchwell, Norfolk, UK, October.

Ernie Janes / Black headed gull (Chroicocephalus / Larus ridibundus) in flight just above water fishing, Titchwell, Norfolk, UK, October.

Aflo / People riding Yonaguni horses in the sea with others floating along holding onto their tails, Nishizaki, Okinawa

Mark Bowler / Red Howler Monkey (Alouatta seniculus) hanging by prehensile tail. Captive at Pilpintuwasi Animal Orphanage.

Mark Bowler / Red Howler Monkey (Alouatta seniculus) hanging by prehensile tail. Captive at Pilpintuwasi Animal Orphanage.

Mark Bowler / Red Howler Monkey (Alouatta seniculus) hanging by prehensile tail. Captive at Pilpintuwasi Animal Orphanage, Padre Cocha, Iquitos, Peru.

Yukihiro Fukuda / Japanese squirrel (Sciurus lis) tail, Mount Yatsugatake, Nagano Prefecture, Japan, August. Endemic species.

Roland Seitre / Brush-tailed phascogale (Phascogale tapoatafa) showing brush like tail, captive, Australia.

Roland Seitre / Resplendent quetzal (Pharomachrus mocinno) close up of tail feathers, captive, from Meso-America.

Roland Seitre / Resplendent quetzal (Pharomachrus mocinno) close up of wing and tail feathers, captive, from Meso-America.

Roland Seitre / Resplendent quetzal (Pharomachrus mocinno) male on branch, Costa Rica.

Roland Seitre / Resplendent quetzal (Pharomachrus mocinno) male on branch, Costa Rica.

Jabruson / Nocturnal tree pangolin (Phataginus tricuspis) resting during the day in hollow tree. Lokoue, Odzala-Kokoua National Park, Cuvette, Republic of Congo.

Jabruson / Nocturnal tree pangolin (Phataginus tricuspis) resting during the day in hollow tree. Lokoue, Odzala-Kokoua National Park, Cuvette, Republic of Congo.

Charlie Summers / Humpback Whale (Megaptera novaeangliae) doing a peduncle throw, the Inside Passage of Alaska, July.

Charlie Summers / Humpback Whale (Megaptera novaeangliae) doing a peduncle throw, the Inside Passage of Alaska, July.

Charlie Summers / Humpback Whale (Megaptera novaeangliae) doing a peduncle throw, the Inside Passage of Alaska, July.

Hiroya Minakuchi / Gray Whale (Eschrichtius robustus) pair raising tails while diving, San Ignacio Lagoon, Baja California, Mexico

Eric Medard / Beaver (Castor fiber) rear view, at night taken with infra red remote camera trap, Sweden, May.

Paul Hobson / Steller's Eider (Polysticta stelleri) diving underwater, Varanger, Norway, March.

Loic Poidevin / Humpback whale (Megaptera novaeangliae) diving, with tail fluke visible above the surface, British Columbia, Canada , June.

Tim Laman / Woolly Monkey (Lagothrix poeppigii) in tree at the Tiputini Biodiversity Station, Orellana Province, Ecuador, July.

Tim Laman / Spider Monkey (Ateles belzebuth) in tree above the clay lick at the Tiputini Biodiversity Station, Orellana Province, Ecuador, July.

Tim Laman / Red Howler Monkey (Alouatta seniculus) in tree near the canopy tower at the Tiputini Biodiversity Station, Orellana Province, Ecuador, July.

MYN / Dimitris Poursanidis / Mediterranean House Gecko (Hemidactylus turcicus) tail, Crete, Greece, August. Meetyourneighbours.net project.

MYN / Andrew Snyder / Emerald tree boa (Corallus caninus) tail, Kanuku Mountains, Guyana. Meetyourneighbours.net project

Roland Seitre / Spencer's monitor (Varanus spenceri) on Astrelba Downs, Bedourie, Queensland, Australia, August

Roland Seitre / Crab-eating macaque (Macaca fascicularis) leaping from rocks into the sea, Thailand

Charlie Summers / Two male Arctic graylings (Thymallus arcticus) displaying to a female, the males vibrate their tails to kick up a fine stream bottom silt, the female ejects roe and the males eject milt into this str...

Charlie Summers / Three male Arctic graylings (Thymallus arcticus) displaying to a female, the males vibrate their tails to kick up a fine stream bottom silt, the female ejects roe and the males eject milt into this s...

Juan Carlos Munoz / Iberian pig close-up of hind legs and tail, Sierra de Aracena Natural Park, Huelva, Andalucia, Spain, Europe. Breed used to produce Iberico ham / Jamon Iberico

Jeff Rotman / Tail of a Rainbow parrotfish (Scarus guacamaia) Bahamas, Caribbean.

Eric Baccega / Humpback whale (Megaptera novaeangliae) fluking, Hecate Strait, British Columbia, Canada, June.