Animal: Quick Facts

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The Information Architects of Encyclopaedia Britannica

Last updated

Oct. 17, 2026

Facts

Also Known As	Animalia

Photos and Videos

Group of fallow deer (Dama dama) stags with large, palmate antlers standing alert in a green summer field.

freshwater jellyfish

gray whale (Eschrichtius robustus)

Side-by-side labeled diagrams of a typical animal cell and a plant cell, showing internal structures such as nucleus, mitochondrion, endoplasmic reticulum, and unique features like chloroplasts and cell wall in the plant cell.

Illustration of various early sea animals on an ocean floor, including jellyfish, ammonites, crinoids, sponges, trilobites, brachiopods, sea scorpions, and a sea snail, with each species labeled.

freshwater sponge (Spongilla)

lobed comb jelly

Gila monster (Heloderma suspectum)

A Caribbean reef squid with a reddish body and white spots swims in clear blue water above a coral reef.

Survival struggles in a meerkat colony

The video thumbnail image shows an illustration of an animal cell next to a photo of a whale swimming in the oean.

Study a jellyfish's muscular contractions and learn how the carnivore uses its tentacles to catch prey

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Topics

Animal social behavior reptile service animal Eumetazoa Parazoa coelomate aquatic animal megafauna fish Animal behaviour plant fungus protist Moneran Bacteria Biology virus taxonomy endangered species Archaea

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Key People

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Charles Elton

English biologist

Akeley, Carl E.

Carl E. Akeley

American naturalist and explorer

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Karl P. Schmidt

American zoologist

Baird, Spencer Fullerton

Spencer Fullerton Baird

American naturalist

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Ross Granville Harrison

American zoologist

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Victor Ernest Shelford

American zoologist

William Harvey

William Harvey

English physician

Georges Cuvier

Georges Cuvier

French zoologist

John James Audubon

John James Audubon

ornithologist, artist, and naturalist

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Warder Clyde Allee

American zoologist

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Sir Gavin de Beer

British zoologist

Theodor Schwann

Theodor Schwann

German physiologist

Donald Redfield Griffin

Donald Redfield Griffin

American biophysicist

Forbes, Edward

Edward Forbes

British naturalist

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Maria Martin

American artist

Jacques Loeb

Jacques Loeb

German biologist

Sewall Wright, 1965

Sewall Wright

American geneticist

Fibiger

Johannes Fibiger

Danish pathologist

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Charles Manning Child

American zoologist

Pallas, engraved portrait

Peter Simon Pallas

German naturalist

Lion (panthera leo)

Deadliest Animals Quiz

Young chimpanzee dressed in a shirt and sweater vest, scratching his head thinking. (primates)

Wild Words from the Animal Kingdom Vocabulary Quiz

Lion (panthera leo)

Deadliest Animals Quiz

The bearded vulture (Gypaetus barbatus) is seen in Switzerland on December 2024

Animal Factoids

The cheetah is the fastest land animal over short distances. It has become an endangered species in Africa, and is almost extinct in Asia. Cheetah mother with young. Cheetah cubs

Moms of the Animal Kingdom Quiz

Mute swan with cygnet. (birds)

Match the Baby Animal to Its Mama Quiz

Mating snails. Extreme close-up

Animal Mating Behavior

Bongo antelopes, Striped antelope called bongos live in the thick rain forests in the southern part of the Central African Republic.

What Kind of Animal?

Band of horses in the saltmarsh at Assateague Island National Seashore, Maryland, Virginia, NPS. Assateague's wild horses are actually feral animals, descendants of domestic animals that have reverted to a wild state.

All About Animals

Nine-Banded Armadillo (Dasypus novemcinctus).

A Is for Animal Quiz

Sea otter (Enhydra lutris), also called great sea otter, rare, completely marine otter of the northern Pacific, usually found in kelp beds. Floats on back. Looks like sea otter laughing. saltwater otters

Animal Group Names

Dromedary camels (Camelus dromedarius). Animals, mammals.

Ultimate Animals Quiz