Aflo / ic-03009 Young domestic kitten asleep in bedding {Felis catus}

Aflo / ic-03007 Young domestic kitten sleeping on bedding {Felis catus}

Aflo / ic-00504 Contented domestic Tabby cat portrait {Felis catus}

Aflo / ic-00502 Contented domestic cat portrait {Felis catus}

Aflo / ic-05307 Puppy asleep on chair.

Edwin Giesbers / Portrait of European otter (Lutra lutra) curled up asleep in the snow, captive, the Netherlands

Marie Read / Common Loon / Great northern diver (Gavia immer) sleepy chick riding on parent's back falls asleep with one foot and one wing in the air, Michigan, USA.

Kristel Richard / Wild Przewalski (or Takhi) horse {Equus ferus przewalski} endangered species, young colt asleep, standing, Hustai National Park, Tuv Province, Mongolia, July 2007

Paul Hobson / Two Mute swan (Cygnus olor) cygnets asleep on parents back, Dorset, UK

Alan Williams / Male Fallow deer (Cervus / Dama dama) asleep, Kent, UK, October

Andy Rouse / Hippopotamus (Hippopotamus amphibius) asleep with oxpeckers on its back, Botswana (non-ex)

Mark Taylor / Buff American Cocker Spaniel puppy, China, 10 weeks old, asleep wearing a Father Christmas hat.

Mark Taylor / Maine Coon kitten asleep in a Christmas hat.

Mark Taylor / Black-and-white kitten asleep in a Father Christmas hat.

Mark Taylor / White Maine Coon kitten asleep wearing a Father Christmas hat.

Mark Taylor / Buff American Cocker Spaniel puppy, China, 10 weeks old, asleep with Father Christmas hat on.

Shattil & Rozinski / White tailed deer {Odocoileus virginianus} fawn curled up asleep, Colorado, USA

Jouan & Rius / Koala (Phascolarctos cinereus) mother with young, asleep, Queensland, Australia

Jouan & Rius / Koala (Phascolarctos cinereus) mother with young asleep, Queensland, Australia

Jouan & Rius / Koala (Phascolarctos cinereus) mother with young asleep, Queensland, Australia

Jouan & Rius / Koala (Phascolarctos cinereus) asleep on branch, Queensland, Australia

Miles Barton / Shingleback / Sleepy lizard (Trachydosaurus / Tiliqua rugosus) asleep on rock, Hawker, Flinders Ranges, South Australia

Miles Barton / Shingleback / Sleepy lizard (Trachydosaurus / Tiliqua rugosus) asleep on rock, Hawker, Flinders Ranges, South Australia

Jane Burton / Baby Grey Squirrel {Sciurus carolinensis}, asleep, 3 weeks old, captive, UK

Jane Burton / Two baby domestic Ferrets {Mustela putorius furo}, curled up, asleep. 3 weeks old

Jane Burton / Baby domestic Ferret {Mustela putorius furo} stretched out asleep 3 weeks old, captive

Jane Burton / Baby Grey Squirrels {Sciurus carolinensis}, asleep, 3 and a half weeks old, captive, UK

Jane Burton / Baby Grey Squirrel {Sciurus carolinensis} asleep, 2 weeks old, captive, UK

Jane Burton / Two Brittany Spaniel pups asleep with chins on floor.

Jane Burton / White German Shepherd Dog / Alsatian pup curled up asleep.

Anup Shah / Banded mongoose {Mungos mungo} pup asleep on back of adult escort, Queen Elizabeth NP, Uganda

Warwick Sloss / Koala sleeping (Phascolarctos cinereus) Healesville Sanctuary, Victoria, Australia

TOM MANGELSEN / Polar Bear (Ursus maritmus) asleep and scratching head, Canada

Michael & Patricia Fogden / Three-toed Sloth (Bradypus infuscatus) silver-backed male asleep in rain, Panama

Chris Gomersall / European brown bear (Ursus arctos) asleep in taiga forest. Finland, Scandinavia. June 2006

Shattil & Rozinski / Baby Deer mouse {Peromyscus maniculatus} curled up asleep in nest, Colorado, USA

SIMON KING / Dingos {Canis dingo} asleep in shade of photographer's tent, Australia

TIM MARTIN / White (tent making) bats {Ectophylla alba} asleep i leaf folds, Atlantic rainforest, Costa Rica

LYNN M. STONE / Grizzly bear {Ursus arctos horribilis} resting head on clump of grass, Alaska, USA

E.A. KUTTAPAN / Two Bengal tigers siblings asleep (Panthera tigris tigris) Bandhavgarh NP, Madhya Pradesh, India. One of Sita's litters.

Eric Baccega / Male Spectacled bear {Tremarctos ornatus} asleep, captive. occurs South America

Eric Baccega / Male Spectacled bear {Tremarctos ornatus} asleep, captive occurs South America

Steven David Miller / Koala {Phascolarctos cinereus} (Northern Form)asleep in tree, Lone Pine Koala Sanctuary, Brisbane, Queensland, Australia.

Nick Garbutt / White footed sportive lemur {Lepilemur leucopus} asleep in tree, Berenty Reserve, Madagascar

Mark Payne-Gill / Arctic fox {Vulpes lagopus} curled up asleep in snow, Canada

Doug Allan / Husky dog sleeping after blizzard, Lancaster Sound, Canadian Arctic

Niall Benvie / Female Tawny owl asleep in tree {Strix aluco} brown phase, Angus, Scotland, captive

Paul Hobson / Two European river otters {Lutra lutra} asleep together, captive

Geoff Simpson / Grey seals asleep in sandstorm on beach {Halichoerus grypus}, North Lincolnshire coast, UK

Owen Newman / Leopard {Panthera pardus} male asleep in tree Southern Luangwa NP, Zambia.

Niall Benvie / Young male European lynx (Lynx lynx) sleeping among bilberry plants, Sumava NP, Bohemia, Czech Republic

Niall Benvie / Young male European lynx (Lynx lynx) eyes closed sleeping, Bohemia, Czech Republic.

Igor Shpilenok / Kamchatka Brown bear (Ursus arctos beringianus) asleep in the Valley of the Geysers, Kronotsky Zapovednik Reserve, Kamchatka, Russia.

Doug Perrine / Bleeker's parrotfish male asleep in mucous cocoon at night {Scarus bleekeri} Malaysia

Doug Perrine / Spotted unicornfish {Naso brevirostris} asleep in coral at night, Micronesia

LYNN M. STONE / Jaguar asleep on tree (Panthera onca) Belize, captive

LYNN M. STONE / Hippos in mud wallow, Zoo. Captive.

Suzi Eszterhas / Three 8-week Cheetah cubs {Acinonyx jubatus} asleep under Acacia bush, Masai Mara, Kenya

Gabriel Rojo / Giant armadillo, head and claws asleep {Priodontes maximus} Argentina, endangered, captive

Gabriel Rojo / Giant armadillo asleep {Priodontes maximus} captive, Argentina, endangered

Doug Wechsler / Mountain chameleon asleep {Chamaeleo montium} Cameroon

Angela Scott / Shadow asleep in tree female leopard {Panthera pardus} Masai

Pete Oxford / Leopard asleep in tree {Panthera pardus} Okavango, Botswana

David Pike / Polar bear asleep with very small cub {Ursus maritimus} Canada

PREMAPHOTOS / Female Nomad bee hangs asleep by jaws (Nomada fabriciana) UK.

Rolf Nussbaumer / Male Green winged teal asleep with head tucked under wing, Texas, USA. {Anas carolinensis}

George McCarthy / Hibernating dormouse {Muscardinus avellanarius} curled up asleep in nest, Sussex, UK

Sumio Harada / Red Squirrel (Tamiasciurus hudsonicus) four babies asleep in nest after nursing, Rocky Mountains, North America

Colin Monteath / Dedicated Antarctic tourist asleep on deckchair during snowfall, Amundsen Sea, Antarctica

Flip de Nooyer / Common Eider (Somateria mollissima) males asleep on water, Europe

George McCarthy / Common dormouse asleep in nest with hazel nut {Muscardinus avellanarius} UK

DAVID TIPLING / Two Dormice asleep in leaves {Muscardinus avellanarius} Kent, UK

Steven David Miller / Orphaned Tasmanian devil babies asleep {Sarcophilus harrisii} Bonorong Wildlife Park, Tasmania

Jeff Rotman / Reef fish asleep amongst fingers of Staghorn Coral (Acropora sp) Red Sea, Egypt

Warwick Sloss / Koala asleep, Healesville Sanctuary (Phascolarctos cinereus) Victoria, Australia

David Shale / Red deer fawn asleep in grass {Cervus elaphus} Scotland, UK

Geoff Simpson / Male (bull) Grey seal asleep on beach {Halichoerus grypus} Lincolnshire, UK

Tony Heald / Hoary bat asleep in tree {Lasiurus cinereus} Galapagos Islands

Pete Oxford / Crowned lemur baby asleep against mother, N. Madagascar, Ankarana Special Reserve

Pete Oxford / Crowned lemur baby (Eulemur coronatus) asleep on mother, Ankarana Special Reserve, North Madagascar

Pete Oxford / Crowned lemur baby (Eulemur coronatus) asleep. Ankarana Special Reserve, Madagascar

Dan Burton / Domestic pig asleep in field {Sus scrofa domestica} female Devon, UK

Martha Holmes / Young male Southern elephant seal asleep on beach, Falkland Islands

Paul Johnson / Fallow deer fawn asleep (Dama dama) England

Mark Payne-Gill / Arctic fox asleep in snow burrow {Vulpes lagopus}

LYNN M. STONE / Domestic rabbit and Piglet asleep, USA, North America

John Downer / Pride of Lions asleep in shade of tree {Panthera leo} Masai Mara, Kenya

Anup Shah / Flying fox {Pteropus genus} asleep and hanging upside down from branch, occurs in Malaysia, South East Asia

TJ Rich / Cape fur seals {Arctocephalus pusillus pusillus} sleeping on beach in sun, Cape Cross, Namibia, Southern Africa

TJ Rich / Adult Red fox {Vulpes vulpes} curled up asleep in grass, England, UK, Europe

Pete Oxford / Patagonia sealion asleep on rock. Chile, South America

Onne van der Wal / Children asleep at sunrise on the foredeck of a cruising catamaran, Bahamas. Model released.

Onne van der Wal / Children asleep at sunrise on the foredeck of a cruising catamaran, Bahamas. Model released.

Onne van der Wal / Children asleep at sunrise on the foredeck of a cruising catamaran, Bahamas. Model released.

Onne van der Wal / Children asleep at sunrise on the foredeck of a cruising catamaran, Bahamas. Model released.