Anup Shah / Hippos courting {Hippopotamus amphibius} Masai Mara NR, Kenya.

Martin Willis / Rainbow Lorikeet (Trichoglossus haematodus) pair preening during courtship, Magnetic Island, Queensland, Australia

Doug Gimesy / Little blue penguin (Eudyptula minor), two standing on rocks at night, silhouetted against Melbourne city lights. St Kilda breakwater, Victoria, Australia. December 2016. COP26 Countdown Photo Competi...

Suzi Eszterhas / Leopard (Panthera pardus) six-week-old cub nuzzling mother, Jao Reserve, Botswana

Winfried Wisniewski / African Lion (Panthera leo) males nuzzling, Masai Mara, Kenya

Mary McDonald / Adult Mountain gorilla (Gorilla beringei beringei) holding baby, Hirwa group, Volcanoes National Park, Rwanda

Willi Rolfes/ BIA / Alpine Marmot (Marmota marmota) parent with young feeding, Hohe Tauern National Park, Austria

Donald M. Jones / White-tailed Deer (Odocoileus virginianus) mother cleaning fawn, Montana

Donald M. Jones / White-tailed Deer (Odocoileus virginianus) doe cleaning newborn fawn, Montana

Donald M. Jones / White-tailed Deer (Odocoileus virginianus) doe smelling newborn fawn, Montana

Donald M. Jones / Black-tailed Prairie Dog (Cynomys ludovicianus) pair greeting, South Dakota

Sue Flood / Emperor penguins (Aptenodytes forsteri) with young chick at Snow Hill Island rookery, Antarctica. October.

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

Marion Vollborn/ BIA / Tiger (Panthera tigris) female with cubs, native to Asia

David Tipling / King penguins (Aptenodytes patagonicus) pair interacting, part of courtship, Gold Harbour South Georgia, January

Brais Seara Fernandez/ BIA / Atlantic Puffin (Fratercula arctica) pair preening, Farne Islands, United Kingdom

Danny Green / Atlantic Puffins (Fratercula arctica) bill rubbing, Skomer Island, Wales, UK, April

Richard Du Toit / Burchell's Zebra (Equus burchellii) pair nuzzling, Rietvlei Nature Reserve, South Africa

Heike Odermatt / Southern Elephant Seal (Mirounga leonina) pups, Sea Lion Island, Falkland Islands

Richard Du Toit / Burchell's Zebra (Equus burchellii) parents tending to foal, Rietvlei Nature Reserve, South Africa

Sergey Gorshkov / Leopard (Panthera pardus) mother licking cub, Londolozi, Sabi-sands Game Reserve, South Africa

Donald M. Jones / Mountain Goat (Oreamnos americanus) kids nuzzling, western Montana

Colin Varndell / Harvest mice (Micromys minutus) on teasel seed head. Dorset, UK, August. Captive.

Gerrit Vyn / Pair of adult Trumpeter Swans (Cygnus buccinator) in flight. Skagit County, Washington. January.

Anup Shah / African Lion (Panthera leo) female with cubs, Masai Mara, Kenya

Pedro Narra / Green turtle (Chelonia mydas) two interacting at surface, Bissagos Islands, Guinea Bissau Endangered species. 3rd Place in the SOS Especes Menacees / SOS Endangered Species Portfolio category of the...

Bence Mate / Two Great egrets (Ardea alba) face to face against white sky, Lake Csaj, Pusztaszer, Hungary. Winner of the Portfolio category of the Terre Sauvage Nature Images Awards competition 2015.

Hiroya Minakuchi / Japanese Macaque (Macaca fuscata) young in hot spring, Jigokudani, Japan

Marie Read / Horned puffins (Fratercula corniculata), one landing with outspread wings, to join its mate on cliff ledge, St. Paul Island, Pribilofs, Alaska, USA, July.

Pete Oxford / Galapagos sealion (Zalophus wollebaeki) mother and pup resting on beach, Galapagos.

Richard Du Toit / South African Giraffe (Giraffa giraffa giraffa) pair courting, KwaZulu-Natal, South Africa

Katherine Feng / Giant Panda (Ailuropoda melanoleuca) eight month old cubs playing in tree, Chengdu, Sichuan, China

Danny Green / Coastal brown bear (Ursus arctos) and cub, Lake Clarke National Park, Alaska, September.

Danny Green / Japanese crane (Grus japonensis) displaying, wings in heart shape, Hokkaido, Japan, February

Enrique Lopez-Tapia / Woman with stick at the Jumping of the bulls Hamer ceremony. This Hamer ceremony, is a right of passage into manhood for Hamer boys. During the ceremony young female relatives of the boys beg to be wh...

Ole Jorgen Liodden / Lioness (Panthera leo) moving her newborn cub, Okavango, Botswana

Bruno de Faveri / Arctic Tern (Sterna paradisaea) with begging chick, Farne Islands, England, United Kingdom

Pete Oxford / Galapagos Sea Lion (Zalophus wollebaeki) mother and pup, Rabida Island, Galapagos Islands, Ecuador

Pete Oxford / Galapagos Sea Lion (Zalophus wollebaeki) mother nuzzling pup, Rabida Island, Galapagos Islands, Ecuador

Pete Oxford / Galapagos Sea Lion (Zalophus wollebaeki) mother nuzzling pup, Rabida Island, Galapagos Islands, Ecuador

Pete Oxford / Galapagos Sea Lion (Zalophus wollebaeki) mother nuzzling pup, Rabida Island, Galapagos Islands, Ecuador

Pete Oxford / Galapagos Sea Lion (Zalophus wollebaeki) mother nuzzling pup, Rabida Island, Galapagos Islands, Ecuador

Tui De Roy / Adelie penguin (Pygoscelis adeliae) courtship behaviour. Prydz Bay, near Davis Station, Vestfold Hills, Ingrid Christensen Coast, East Antarctica, November.

Suzi Eszterhas / Hoffmann's Two-toed Sloth (Choloepus hoffmanni) mother and two month old baby, Aviarios Sloth Sanctuary, Costa Rica

Suzi Eszterhas / Hoffmann's Two-toed Sloth (Choloepus hoffmanni) mother and two month old baby, Aviarios Sloth Sanctuary, Costa Rica

Suzi Eszterhas / Hoffmann's Two-toed Sloth (Choloepus hoffmanni) mother and two month old baby, Aviarios Sloth Sanctuary, Costa Rica

Suzi Eszterhas / Proboscis Monkey (Nasalis larvatus) mother holding baby, Sabah, Borneo, Malaysia

Suzi Eszterhas / Proboscis Monkey (Nasalis larvatus) baby clinging to mother, Sabah, Borneo, Malaysia

Ingo Arndt / European Beaver (Castor fiber) grooming newborn baby inside lodge, Germany

Donald M. Jones / Burrowing Owl (Athene cunicularia) owlet greeting parent, Montana

Stefan Christmann / Emperor Penguin (Aptenodytes forsteri) pair courting, Queen Maud Land, Antarctica

Stefan Christmann / Emperor Penguin (Aptenodytes forsteri) parents with chick, Queen Maud Land, Antarctica

Stefan Christmann / Emperor Penguin (Aptenodytes forsteri) parents with chicks, Queen Maud Land, Antarctica

Richard Du Toit / Impala (Aepyceros melampus) mother nuzzling one month old calf, Chobe National Park, Botswana

Richard Du Toit / Burchell's Zebra (Equus burchellii) mother nuzzling foal, Rietvlei Nature Reserve, South Africa

Suzi Eszterhas / Indian Rhinoceros (Rhinoceros unicornis) mother and one week old calf, Kaziranga National Park, India, digitally removed grass from foreground

Suzi Eszterhas / Capybara (Hydrochoerus hydrochaeris) mother and pup on riverbank, Pantanal, Brazil

Thomas Marent / Japanese Macaque (Macaca fuscata) mother holding baby for warmth, Jigokudani, Nagano, Japan

Anup Shah / African Lion (Panthera leo) female nuzzling one year old cub, Masai Mara, Kenya

Fiona Rogers / Silvered Leaf Monkey (Trachypithecus cristatus) mother with five month old baby, Bako National Park, Sarawak, Borneo, Malaysia

Roland Seitre / Dingo (Canis lupus dingo) black and white pup, native to Australia

Matthias Breiter / Polar Bear (Ursus maritimus) mother and three-month-old cubs, Wapusk National Park, Manitoba, Canada

Donald M. Jones / Sea Otter (Enhydra lutris) mother and pup, Prince William Sound, Alaska

Hiroya Minakuchi / Black-footed Penguin (Spheniscus demersus) pair courting, Cape Peninsula, South Africa

Kevin Schafer / Gentoo Penguin (Pygoscelis papua) parent with chicks, Pleneau Island, Antarctic Peninsula, Antarctica

Fiona Rogers / Japanese Macaque (Macaca fuscata) female holding her baby, Jigokudani Monkey Park, Japan

Fiona Rogers / Japanese Macaque (Macaca fuscata) female cuddling her baby, Jigokudani Monkey Park, Japan

Jiri Slama / Northern Gannet (Morus bassanus) pair in courting display, Bass Rock, Scotland, United Kingdom

Tui De Roy / Blue-footed Booby (Sula nebouxii) pair courting, Santa Cruz Island, Galapagos Islands, Ecuador

Fiona Rogers / Sumatran Orangutan (Pongo abelii) twenty-four year old female, named Ratna, playing with her female baby, named Global, Gunung Leuser National Park, Sumatra, Indonesia

Suzi Eszterhas / Koala (Phascolarctos cinereus) mother cuddling her seven-month-old joey, Queensland, Australia

Sergey Gorshkov / Snow Goose (Chen caerulescens) pair courting, Wrangel Island, Russia. Sequence 3 of 4

Cyril Ruoso / Bonobo (Pan paniscus) female with newborn, Sanctuary Lola Ya Bonobo Chimpanzee, Democratic Republic of the Congo

Cyril Ruoso / Bonobo (Pan paniscus) pair of orphans hugging, Sanctuary Lola ya Bonobo, Democratic Republic of the Congo

Cyril Ruoso / Giant Panda (Ailuropoda melanoleuca) female and year old cub playing, Chengdu Panda Breeding Research Center, China

Cyril Ruoso / Barbary Macaque (Macaca sylvanus) resting infant carried on its mother's back, Morocco

Richard Du Toit / Burchell's Zebra (Equus burchellii) pair nuzzling, Rietvlei Nature Reserve, Gauteng, South Africa

Richard Du Toit / Burchell's Zebra (Equus burchellii) pair, Rietvlei Nature Reserve, Gauteng, South Africa

Suzi Eszterhas / Mountain Gorilla (Gorilla gorilla beringei) mother holding five month old twin babies, Parc National des Volcans, Rwanda

Suzi Eszterhas / Mountain Gorilla (Gorilla gorilla beringei) mother holding five month old twin babies, Parc National des Volcans, Rwanda

Kevin Schafer / Galapagos Sea Lion (Zalophus wollebaeki) pups playing, Espanola Island, Galapagos Islands, Ecuador

Ingo Arndt / Grizzly Bear (Ursus arctos horribilis) mother with cub, Lake Clark National Park, Alaska

Suzi Eszterhas / Bengal Tiger (Panthera tigris tigris) six week old cub on sleeping mother at den, Bandhavgarh National Park, India

Suzi Eszterhas / Bengal Tiger (Panthera tigris tigris) five week old cub resting on sleeping mother at den, Bandhavgarh National Park, India

Konrad Wothe / Japanese Macaque (Macaca fuscata) grooming young in snow, Japanese Alps, Japan

Donald M. Jones / Dall's Sheep (Ovis dalli) rams, Denali National Park, Alaska

Donald M. Jones / Dall's Sheep (Ovis dalli) rams, Denali National Park, Alaska

Andrew Parkinson / Mute swans (Cygnus olor) pair of adults engaged in a courtship dance, Nottinghamshire, UK, February.

Anup Shah / Lioness (Panthera leo) and cub aged 9-12 months share affectionate moment, Masai Mara National Reserve, Kenya

Lisa Hoffner / Two orphan baby Elephants (Loxodonta africana) being affectionate. David Sheldrick Wildlife Trust Nairobi Elephant Nursery, Kenya, July 2010.

Diane McAllister / A wild newborn colt (Equus caballus) standing up being nuzzled by its mother. Foothills of Reno, Nevada, USA, May.

ZSSD / Rothschild Giraffe (Giraffa camelopardalis rothschildi) mother and calf nuzzling, native to Africa

Anup Shah / Bornean Orangutan (Pongo pygmaeus wurmbii) female 'Lady Di' with her son 'La Betty' aged 3 years portrait. Camp Rasak, Lamandau Nature Reserve, Central Kalimantan, Borneo, Indonesia. July 2010. Rehabi...

Mitsuaki Iwago / Japanese Macaque (Macaca fuscata) mother grooming young, Jigokudani, Japan

Tui De Roy / Galapagos Sea Lion (Zalophus wollebaeki) female and pup nuzzling, Galapagos Islands, Ecuador

Suzi Eszterhas / Sea Otter (Enhydra lutris) mother holding one week old pup, Monterey Bay, California