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mammal
Table of Contents
References & Edit History Quick Facts & Related Topics
Images & Videos
polar bear and cubs okapi faunal realms goat herding Steller's sea cow bottlenose dolphins journey of a fertilized egg embryonic development leopard Yellowstone wolf pack
For Students
polar bear and cubs
mammal summary
Quizzes
Dromedary camels (Camelus dromedarius). Animals, mammals.
Ultimate Animals 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
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
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
Related Questions
Read Next
animal. Amphibian. Frog. Anura. Ranidae. Frog in grass.
Abundant Animals: The Most Numerous Organisms in the World
cat. orange and white persian cat with long hair, snarl, growl, teeth
7 Questions About Mammals Answered
sea turtle (reptile). Green turtle (Chelonia mydas) (C. mydas) off the Hawaii Islands, Pacific Islands. Green sea turtle, chelonian. Homepage blog 2011, science and technology, animal
5 Vertebrate Groups
Platypus (Ornithorhynchus anatinus) swimming on the surface of a creek. Water Australia mammal monotreme
Why Is the Platypus a Mammal?
Ruminant. Deer. Red deer. Cervus elaphus. Buck. Stag. Antlers.
9 of the World’s Deadliest Mammals
Discover
Calendar showing the month of February
Why Are There Only 28 Days in February?
Aphrodite. Greek mythology. Sculpture. Aphrodite is the Greek goddess of love and beauty.
12 Greek Gods and Goddesses
Amendments 1-10 to the Constitution of the United States constitute what is known as the Bill of Rights on an American flag.
What Is the Emoluments Clause?
Bar graph of the United States Death Toll during major events. Infogram chart.
U.S. Death Toll During Major Events
Groups of depositors in front of the closed American Union Bank, New York City. April 26, 1932. Great Depression run on bank crowd
Causes of the Great Depression
Common, or southern, cassowary (Casuarius casuarius).
8 Birds That Can’t Fly
Ruminant. Deer. Red deer. Cervus elaphus. Buck. Stag. Antlers.
9 of the World’s Deadliest Mammals

mammal: Facts & Related Content

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News •

Researchers uncover key biological mechanism that prevents sperm-egg fusion • Mar. 3, 2025, 9:54 PM ET (News-Medical)

Facts

Also Known As Mammalia

Photos and Videos

polar bear and cubs
okapi
faunal realms
goat herding
Steller's sea cow
bottlenose dolphins
journey of a fertilized egg
embryonic development
leopard
Yellowstone wolf pack
The video thumbnail shows a small squirrel peeking out of a snowy bank, with a blue circle surrounding it.
Which mammals have the shortest and longest gestations
See All Videos and Images →

Related Topics and References

Topics
Dig Deeper: More Articles That Discuss This Topic

Key People

Steen Willadsen
Danish embryologist
Karl Ernst, Ritter von Baer
Karl Ernst von Baer
Prussian-Estonian embryologist
George Gaylord Simpson
American paleontologist
Purkinje, Jan Evangelista
Jan Evangelista Purkinje
Czech physiologist
Voit, Carl von
Carl von Voit
German physiologist
Baird, Spencer Fullerton
Spencer Fullerton Baird
American naturalist
Geoffrey Bourne
American anatomist
William Diller Matthew
William Diller Matthew
Canadian-American paleontologist
Flower, 1883
Sir William Henry Flower
British zoologist
Reinier de Graaf, engraving by an unknown artist
Reinier de Graaf
Dutch physician
Reginald Innes Pocock
English zoologist
John Bachman
American naturalist and minister

Related Quizzes and Features

Quiz
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
vulture. An adult bearded vulture at a raptor recovery center. The Gypaetus barbatus also known as the Lammergeier or Lammergeyer, is a bird of prey and considered an Old World vulture.
Animal Factoids
Dromedary camels (Camelus dromedarius). Animals, mammals.
Ultimate Animals Quiz
Lion (panthera leo)
Deadliest Animals 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
Nine-Banded Armadillo.
A Is for Animal Quiz
Giraffe standing in grass, Kenya.
Know Your Mammals Quiz
Mute swan with cygnet. (birds)
Match the Baby Animal to Its Mama Quiz
Lion (panthera leo)
Deadliest Animals Quiz
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
Young chimpanzee dressed in a shirt and sweater vest, scratching his head thinking. (primates)
Wild Words from the Animal Kingdom Vocabulary Quiz
List
Ruminant. Deer. Red deer. Cervus elaphus. Buck. Stag. Antlers.
9 of the World’s Deadliest Mammals
sea turtle (reptile). Green turtle (Chelonia mydas) (C. mydas) off the Hawaii Islands, Pacific Islands. Green sea turtle, chelonian. Homepage blog 2011, science and technology, animal
5 Vertebrate Groups
cat. orange and white persian cat with long hair, snarl, growl, teeth
7 Questions About Mammals Answered
animal. Amphibian. Frog. Anura. Ranidae. Frog in grass.
Abundant Animals: The Most Numerous Organisms in the World