Stefan Christmann / Emperor penguin (Aptenodytes forsteri) pair in courtship, on sea ice. Atka Bay, Antarctica. May.

Jack Dykinga / Burrowing owl (Athene cunicularia), two huddled together. Marana, Pima County, Arizona, USA.

Anup Shah / Southern plains grey langur / Hanuman langur (Semnopithecus dussumieri) females hugging to reinforce rank. Jodhpur, Rajasthan, India. March.

Fiona Rogers / Southern plains grey langur / Hanuman langur (Semnopithecus dussumieri) infant aged a few weeks. Jodhpur, Rajasthan, India. March.

Edwin Giesbers / Brown headed spider monkey (Ateles fusciceps) mother and baby, captive occurs in Central and South America.

Edwin Giesbers / Brown headed spider monkey (Ateles fusciceps) group resting together, captive occurs in Central and South America.

Klein & Hubert / Tabby and white mother and kitten (age 7 weeks) in garden. France.

Anup Shah / Eastern chimpanzee (Pan troglodytes schweinfurtheii) young baby of adolescent female 'Golden' suckling. Gombe National Park, Tanzania.

Pascal Pittorino / Mediterranean tree frogs (Hyla meridionalis) mating on a branch of Quince tree (Cydonia oblonga) Var, Provence, France, April.

Yukihiro Fukuda / Japanese macaque (Macaca fuscata fuscata) mother with rare white furred male baby, Jigokudani Valley, Nagano Prefecture, Japan. June.

Aflo / Japanese macaque (Macaca fuscata) mother cuddling baby, Yamanouchi, Shimotakai District, Nagano Prefecture, Japan. June.

Suzi Eszterhas / Koala (Phascolarctos cinereus) mother with joey aged eight months, Queensland, Australia, captive.

Will Burrard-Lucas / Meerkat (Suricata suricatta) adult with babies, Makgadikgadi Pans, Botswana.

Anup Shah / Olive baboon (Papio cynocephalus anubis) juvenile cuddling an infant aged 9-12 months, Masai Mara National Reserve, Kenya, August

Anup Shah / Bornean Orangutan (Pongo pygmaeus wurmbii) female 'Unyuk' cuddling her daughter 'Ursula', age 4 years. Camp Leakey, Tanjung Puting National Park, Central Kalimantan, Borneo, Indonesia. June 2010. Reha...

Anup Shah / Bornean Orangutan (Pongo pygmaeus wurmbii) female 'Unyuk' cuddling her daughter 'Ursula' aged 4 - portrait. Camp Leakey, Tanjung Puting National Park, Central Kalimantan, Borneo, Indonesia. June 2010....

Florian Möllers / Golden snub-nosed monkeys (Rhinopithecus roxellana qinlingensis) family group / harem resting / sleeping / cuddling, Zhouzhi Nature Reserve, Qinling mountains, Shaanxi, China, April 2006

Yukihiro Fukuda / Japanese macaque / Snow monkey {Macaca fuscata} two monkeys huddle together to keep warm, Jigokudani, Nagano, Japan

Jean-Pierre Zwaenepoel / Southern plains grey / Hanuman langur {Semnopithecus dussumieri} adult females embracing, Thar desert, Rajasthan, India

Anup Shah / Cheetah cub cuddling up to mother {Acinonyx jubatus} Masai Mara, Kenya

Anup Shah / Female Chimpanzee 'Fanni' with offspring 'Fundi' (male, 17-months-old) and Fudge (male, 4-years-10-months-old) {Pan troglodytes schweinfurtheii}, Kasekela community, Gombe NP, Tanzania. 2002

Ingo Arndt / European River Otter (Lutra lutra) sisters resting, Europe

Ingo Arndt / European River Otter (Lutra lutra) sisters resting, Europe

Suzi Eszterhas / Koala (Phascolarctos cinereus) mother and joey, Kangaroo Island, Australia

Cyril Ruoso / Verreaux's Sifaka (Propithecus verreauxi) trio huddling, vulnerable, Berenty Private Reserve, Madagascar

Matthias Breiter / Polar Bear (Ursus maritimus) female with twelve week old cub, Canada

Matthias Breiter / Polar Bear (Ursus maritimus) mother with cub, Churchill, Manitoba, Canada

Suzi Eszterhas / Sea Otter (Enhydra lutris) mother with three day old newborn pup, Monterey Bay, California

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

Fiona Rogers / Southern Plains Gray Langur (Semnopithecus dussumieri) newborn with mother, Jodhpur, Rajasthan, India

Sean Crane / Mountain Gorilla (Gorilla gorilla beringei) mother and young, Bwindi Impenetrable National Park, Uganda

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

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

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 mother cuddling her seven-month-old joey, Queensland, Australia

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

Vincent Grafhorst / Black-faced Vervet Monkey (Cercopithecus aethiops) baby clinging to mother, Moremi Game Reserve, Okavango Delta, Botswana

Gerry Ellis / Koala (Phascolarctos cinereus) mother and three month old joey in tree, Australia

Gerry Ellis / Koala (Phascolarctos cinereus) mother and joey, three month old, Australia

Gerry Ellis / Koala (Phascolarctos cinereus) mother and joey, three month old, Australia

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

Michio Hoshino / Polar Bear (Ursus maritimus) mother and two cubs, Churchill, Manitoba, Canada

Cyril Ruoso / Red fox (Vulpes vulpes), two cubs huddled together near den. Yonne France. May.

Cyril Ruoso / Red fox (Vulpes vulpes), three cubs huddled together outside den. Yonne France. May.

Guy Edwardes / Common dwarf mongoose (Helogale parvula), three on tree trunk. Savuti, Chobe National Park, Botswana.

Suzi Eszterhas / Spotted hyena (Crocuta crocuta) female and cub. Mashatu Game Reserve, Botswana.