Mammals, GRO-JUM

Mammals are distinguished by their ability to produce milk. The class Mammalia boasts tremendous diversity in form and habit, and different types of mammals can be wildly different from one another in physical appearance. Living kinds of mammals range in size from a bat weighing less than a gram to the largest animal that has ever lived, the blue whale, which reaches a length or more than 30 metres (100 feet) and a weight of 180 metric tons (nearly 200 short [U.S.] tons).
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Mammals Encyclopedia Articles By Title

groundhog
groundhog, (Marmota monax), one of 14 species of marmots (Marmota), considered basically a giant North American......
guanaco
guanaco, (Lama guanicoe), South American member of the camel family (Camelidae, order Artiodactyla) that is closely......
guenon
guenon, (genus Cercopithecus), any of 26 species of widely distributed African monkeys characterized by bold markings......
guereza
guereza, any of several species of colobus monkeys distinguished by their black and white pelts, especially Colobus......
Guernsey
Guernsey, breed of dairy cattle originating on Guernsey, one of the Channel Islands. Like the Jersey, this breed......
guide dog
guide dog, dog that is professionally trained to guide, protect, or aid its master. Systematic training of guide......
guinea pig
guinea pig, (Cavia porcellus), a domesticated species of South American rodent belonging to the cavy family (Caviidae).......
gundi
gundi, (family Ctenodactylidae), any of five North African species of rodents distinguished by its comblike rows......
gymnure
gymnure, (subfamily Galericinae), any of eight species of hedgehoglike mammals having a long muzzle with a protruding......
Hackney
Hackney, stylish carriage horse breed, now used primarily as a show horse. It was developed in the 18th century......
Hackney pony
Hackney pony, heavy harness pony breed derived from the cross of a Hackney horse and a Welsh pony, used almost......
hamadryas
hamadryas, (Papio hamadryas), large, powerful monkey of the plains and open-rock areas of the Red Sea coast, both......
Hampshire
Hampshire, breed of pig developed in the United States from the Wessex Saddleback and other varieties first imported......
Hampshire
Hampshire, breed of medium-wool, dark-faced, hornless sheep originating in Hampshire, England. It is large and......
hamster
hamster, (subfamily Cricetinae), any of 18 Eurasian species of rodents possessing internal cheek pouches. The golden......
harbour seal
harbour seal, (Phoca vitulina), nonmigratory, earless seal (family Phocidae) found throughout the Northern Hemisphere.......
hare
hare, (genus Lepus), any of about 30 species of mammals related to rabbits and belonging to the same family (Leporidae).......
harp seal
harp seal, (Pagophilus, or Phoca, groenlandica), medium-sized, grayish earless seal possessing a black harp-shaped......
hartebeest
hartebeest, (Alcelaphus buselaphus), large African antelope (family Bovidae) with an elongated head, unusual bracket-shaped......
harvest mouse
harvest mouse, either of two genera of small mice: the American harvest mouse (Reithrodontomys) or the Old World......
hedgehog
hedgehog, (subfamily Erinaceinae), any of 15 Old World species of insectivores possessing several thousand short,......
Heidelberg jaw
Heidelberg jaw, enigmatic human mandible, thought to be about 500,000 years old, found in 1907 in the great sandpit......
heifer
heifer, any young, female, domestic bovine that has not produced offspring. At birth, a female calf is often termed......
Hell in a Handbag
An earlier version of this article was published on the Britannica blog Advocacy for Animals. Thorstein Veblen,......
herding dog
herding dog, any of several breeds of dogs that herd livestock. They also typically make fine family pets or obedience......
Hereford
Hereford, popular breed of beef cattle, the product of generations of breeding work on the part of landed proprietors......
Himalayan
Himalayan, breed of domestic cat with the colouring of the Siamese and the build and coat of the longhair, or Persian.......
hippopotamus
hippopotamus, (Hippopotamus amphibius), amphibious African ungulate mammal. Often considered to be the second largest......
Hipposiderinae
Hipposiderinae, subfamily of insect-eating bats, suborder Microchiroptera, family Rhinolophidae, with 9 genera......
hoary bat
hoary bat, (Lasiurus cinereus), migratory North American bat found in wooded areas from Canada to Mexico. It is......
hog
hog, Heavy, fat-producing domesticated pig developed in the U.S. in the late 19th and early 20th century. As the......
Holstein-Friesian
Holstein-Friesian, breed of large piebald dairy cattle originating in northern Holland and Friesland and highly......
Hominidae
Hominidae, in zoology, one of the two living families of the ape superfamily Hominoidea, the other being the Hylobatidae......
hominin
hominin, any member of the zoological “tribe” Hominini (family Hominidae, order Primates), of which only one species......
Homo
Homo, genus of the family Hominidae (order Primates) characterized by a relatively large cranial capacity, limb......
Homo erectus
Homo erectus, extinct species of the human genus (Homo), perhaps an ancestor of modern humans (Homo sapiens). H.......
Homo floresiensis
Homo floresiensis, taxonomic name given to an extinct hominin (member of the human lineage) that is presumed to......
Homo habilis
Homo habilis, extinct species of human, the most ancient representative of the human genus, Homo. Homo habilis......
Homo heidelbergensis
Homo heidelbergensis, extinct species of archaic human (genus Homo) known from fossils dating from 600,000 to 200,000......
Homo naledi
Homo naledi, extinct species of human, initially thought to have evolved about the same time as the emergence of......
Homo sapiens
Homo sapiens, the species to which all modern human beings belong. Homo sapiens is one of several species grouped......
Homo sapiens sapiens
Homo sapiens sapiens, in anthropology and paleontology, the subspecies of Homo sapiens that consists of the only......
hooded seal
hooded seal, (Cystophora cristata), large grayish seal with dark spots that is found in open waters of the North......
horse
horse, (Equus caballus), a hoofed herbivorous mammal of the family Equidae. It comprises a single species, Equus......
horse breeds
Horses were among the last species of livestock to be domesticated. Their domestication took place at least as......
horseshoe bat
horseshoe bat, (genus Rhinolophus), any of more than 100 species of large-eared insect-eating bats that make up......
Horsing Around: 7 of the Weirdest Racehorse Names in History
The naming of racehorses is governed in the U.S. by the Jockey Club. They have the difficult task of deciding which......
hound
hound, Classification of hunting dogs that is more general than setter, retriever, pointer, or other sporting dog......
house mouse
house mouse, (Mus musculus), rodent native to Eurasia but introduced worldwide through association with humans.......
How Big Was a Saber-Toothed Tiger?
The saber-toothed tiger, the popular name for a genus of extinct prehistoric cats known as Smilodon, was about......
How Big Was the Woolly Mammoth?
The woolly mammoth (Mammuthus primigenius) was a massive creature, standing about 3 to 3.7 meters (about 10 to......
How Big Were Saber-Toothed Cats Compared to Tigers?
Saber-toothed cats in the genus Smilodon were comparable in length and height to Siberian tigers (Panthera tigris......
How Did the Sperm Whale Get Its Name?
Sperm whales (Physeter catodon), or cachalots, are the largest of the toothed whales, with males up to 19 meters......
How Do Horses Sleep?
Horses sleep both standing up and lying down. Most of their sleeping time is spent standing, which is crucial for......
How Do Monkeys and Apes Trim Their Fingernails?
Have you ever seen a monkey getting a manicure? Though that line sounds like the beginning of a bad joke, it actually......
How Fast Are Cheetahs?
Cheetahs are capable of reaching speeds of up to 114 km (71 miles) per hour, making them the fastest land animals.......
How Fast Can Bears Run?
Bears, despite their at times lumbering appearance, can move at impressive speeds in pursuit of prey. The fastest......
How Intelligent Are Dolphins?
Dolphins are highly intelligent animals, and this intelligence appears in many aspects of their lives. One well-documented......
How Long Can Whales Hold Their Breath?
Whales can hold their breath for varying durations depending on the species, with some capable of staying submerged......
How Long Do Elephants Live?
Elephants have varied lifespans depending on whether they live in the wild or in captivity. The lifespan of wild......
How Long Do Tigers Live?
Tigers typically live for 10–15 years in the wild but longer in captivity, sometimes reaching 20 years or more.......
How Many Stomachs Does a Cow Have?
Cows do not have four stomachs, as is sometimes thought. They have one stomach divided into four compartments—the......
How Much Does a Hippopotamus Weigh?
A hippopotamus typically weighs up to 3,200 kg (3.5 tons). As the second-largest land mammal after the elephant,......
How Much Does an Elephant Weigh?
The short answer? A lot. The African bush elephant (Loxodonta africana), also known as the African savanna elephant,......
How Tall Are Giraffes?
Giraffes are the tallest land animals. Males (bulls) may exceed 5.5 meters (18 feet) in height, and females (cows)......
howler monkey
howler monkey, (genus Alouatta), any of several tropical American monkeys noted for their roaring cries. Several......
Human Ancestors
Modern human beings—that is, the species Homo sapiens—emerged relatively recently, only about 315,000 to 150,000......
humpback whale
humpback whale, (Megaptera novaeangliae), a baleen whale known for its elaborate courtship songs and displays.......
hutia
hutia, (family Capromyidae), any of 26 living and recently extinct species of Caribbean rodents. The surviving......
Hyaenodon
Hyaenodon, extinct genus of carnivorous mammals that first appeared in the fossil record about 42 million years......
hyena
hyena, (family Hyaenidae), any of three species of coarse-furred, doglike carnivores found in Asia and Africa and......
hyrax
hyrax, (order Hyracoidea), any of six species of small hoofed mammals (ungulates) native to Africa and extreme......
Iberian lynx
Iberian lynx, (species Lynx pardinus), medium-sized wild cat endemic to the Iberian Peninsula in southwestern Europe.......
ibex
ibex, any of several sure-footed, sturdy wild goats of the genus Capra in the family Bovidae (order Artiodactyla)......
impala
impala, (Aepyceros melampus), swift-running antelope, the most abundant ruminant in the savannas of eastern and......
incubation
incubation, the maintenance of uniform conditions of temperature and humidity to ensure the development of eggs......
Indian rhinoceros
Indian rhinoceros, (Rhinoceros unicornis), the largest of the three Asian rhinoceroses. The Indian rhinoceros weighs......
indri
indri, (Indri indri), slender, long-limbed primate found in the forests of Madagascar. The largest of the lemurs,......
Indricotherium
Indricotherium, genus of giant browsing perissodactyls found as fossils in Asian deposits of the Late Oligocene......
Indridae
Indridae, family of arboreal Madagascan primates. See avahi; indri;...
insectivore
insectivore, the common name applied to any of 450 or so species of mammals—comprising hedgehogs, golden moles,......
Irish elk
Irish elk, (Megaloceros giganteus), extinct species of deer, characterized by immense body size and wide antlers,......
Irish Setter
Irish Setter, breed of sporting dog renowned for its elegant build, graceful gait, and bright mahogany-colored......
Irish terrier
Irish terrier, dog developed in Ireland, one of the oldest breeds of terriers. Nicknamed the “daredevil,” it has......
Irish water spaniel
Irish water spaniel, breed of sporting dog developed in Ireland in the 1830s for retrieving game; its ancestors......
Irish wolfhound
Irish wolfhound, tallest of all dog breeds, a keen-sighted hound used in Ireland for many years to hunt wolves......
Is It True That Squirrels Forget Where They Bury About Half of Their Food?
The verdict is out on whether squirrels forget about half of the nuts they bury: surely some squirrels do. Forgotten......
Is It Wrong to Own a Flat-Faced Dog?
Are flat-faced dogs ugly or cute? It all depends on whom you ask. Although many of us have a hard time understanding......
Jack Russell Terrier
Jack Russell Terrier, breed of terrier developed in England in the 19th century for hunting foxes both above- and......
jackal
jackal, any of several species of wolflike carnivores of the dog genus, Canis, family Canidae, sharing with the......
jackrabbit
jackrabbit, any of several North American species of hare (genus...
jaguar
jaguar, (Panthera onca), largest New World member of the cat family (Felidae), found from northern Mexico southward......
jaguarundi
jaguarundi, (Puma yagouaroundi), small, unspotted New World cat (family Felidae), also known as the otter-cat because......
Jamaican fruit bat
Jamaican fruit bat, (Artibeus jamaicensis), a common and widespread bat of Central and South America with a fleshy......
Japanese spaniel
Japanese spaniel, breed of toy dog that originated in China and was introduced to Japan, where it was kept by royalty.......
Java man
Java man, extinct hominin (member of the human lineage) known from fossil remains found on the island of Java,......
Javan rhinoceros
Javan rhinoceros, (Rhinoceros sondaicus), one of three Asian species of rhinoceroses, found only on the island......
jerboa
jerboa, any of 33 species of long-tailed leaping rodents well adapted to the deserts and steppes of eastern Europe,......
Jersey
Jersey, breed of small short-horned dairy cattle originating on Jersey, one of the Channel Islands; it is believed......
jumping mouse
jumping mouse, (subfamily Zapodinae), any of five species of small leaping rodents found in North America and China.......

Mammals Encyclopedia Articles By Title