Placental Mammals, LAG-NOR

Placental mammal, (infraclass Eutheria), any member of the mammalian group characterized by the presence of a placenta, which facilitates exchange of nutrients and wastes between the blood of the mother and that of the fetus. The placentals include all living mammals except marsupials and monotremes. Although some authorities consider the marsupials (cohort Marsupialia) to be placental mammals, these animals have a less-developed, less-efficient type of placenta that limits the gestation period. The true placenta of the placentals allows for a longer developmental period within the protection of the womb, a factor considered to have contributed to the evolutionary success of the group. Fossil evidence shows that the first placental mammals evolved between about 163 million and 157 million years ago during the Jurassic Period (201.3 million to about 145 million years ago).
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Placental Mammals Encyclopedia Articles By Title

lagomorph
lagomorph, (order Lagomorpha), any member of the mammalian order made up of the relatively well-known rabbits and......
Lakeland terrier
Lakeland terrier, breed of dog originally used to hunt and kill foxes in the Lake District of England. Formerly......
LaMancha
LaMancha, American breed of dairy goat known for its much-reduced external ears. The lineage of LaManchas is uncertain;......
lamb
lamb, live sheep before the age of one year and the flesh of such an animal. Mutton refers to the flesh of the......
langur
langur, general name given to numerous species of Asian monkeys belonging to the subfamily Colobinae. The term......
Lantian man
Lantian man, fossils of hominins (members of the human lineage) found in 1963 and 1964 by Chinese archaeologists......
large mouse-eared bat
large mouse-eared bat, species of brown bat...
laughing hyena
laughing hyena, African species of hyena...
leaf-nosed bat
leaf-nosed bat, any of almost 250 species of New World and Old World bats belonging to the families Phyllostomidae......
lechwe
lechwe, (genus Kobus), antelope species of the genus Kobus. The lechwe, a member of the waterbuck and kob tribe......
lemming
lemming, any of 20 species of small rodents, some of which undertake large, swarming migrations. Lemmings are found......
lemur
lemur, (suborder Strepsirrhini), generally, any primitive primate except the tarsier; more specifically, any of......
leopard
leopard, (Panthera pardus), large cat closely related to the lion, tiger, and jaguar. The name leopard was originally......
leopard cat
leopard cat, (Prionailurus bengalensis), forest-dwelling cat, of the family Felidae, found across India, Southeast......
leopard seal
leopard seal, (Hydrurga leptonyx), generally solitary, earless seal (family Phocidae) that inhabits Antarctic and......
Lhasa Apso
Lhasa Apso, breed of small sturdy dog from Tibet, where it is called abso seng kye (variously translated as “bark......
liger
liger, offspring of a male lion and a female tiger. The liger is a zoo-bred hybrid, as is the tigon, which is the......
linsang
linsang, any of three species of long-tailed, catlike mammals belonging to the civet family (Viverridae). The African......
lion
lion, (Panthera leo), large, powerfully built cat (family Felidae) that is second in size only to the tiger; it......
Lipizzaner
Lipizzaner, breed of horse that derived its name from the Austrian imperial stud at Lipizza, near Trieste, formerly......
litoptern
litoptern, (order Litopterna), any of various extinct hoofed mammals that first appeared in the Paleocene Epoch......
llama
llama, (Lama glama), domesticated livestock species, descendant of the guanaco (Lama guanicoe), and one of the......
Llanocetus denticrenatus
Llanocetus denticrenatus, one of the earliest known baleen whales, sole member of the family Llanocetidae, suborder......
long-eared bat
long-eared bat, any of 19 species of small, usually colony-dwelling vesper bats (family Vespertilionidae). Long-eared......
longhair
longhair, breed of domestic cat noted for its long, soft, flowing coat. Long-haired cats were originally known......
Longhair Cat Breeds
Longhair cats are defined by their luxurious coats. Here’s a sampling of 11 longhair breeds. list, cats, pets,......
loris
loris, (subfamily Lorisinae), any of about 14 species of tail-less or short-tailed South and Southeast Asian forest......
Lucy
Lucy, nickname for a remarkably complete (40 percent intact) hominin skeleton found by American paleoanthropologist......
lynx
lynx, (genus Lynx), any of four species of short-tailed cats (family Felidae) found in the forests of Europe, Asia,......
Maba cranium
Maba cranium, fossil fragments of an ancient human skull found in 1958 near the village of Maba (Ma-pa), Guangdong......
macaque
macaque, (genus Macaca), any of more than 20 species of gregarious Old World monkeys, all of which are Asian except......
Maine coon cat
Maine coon cat, North America’s only native breed of longhaired domestic cat. Though its origins are unknown, it......
Malayan lar
Malayan lar, species of gibbon...
Maltese
Maltese, breed of toy dog named for the island of Malta, where it may have originated more than 2,500 years ago.......
mammoth
mammoth, (genus Mammuthus), any member of an extinct group of elephants found as fossils in Pleistocene deposits......
manatee
manatee, (genus Trichechus), any of three species of large slow aquatic mammals found along tropical and subtropical......
Manchester terrier
Manchester terrier, breed of dog developed in England from the whippet, a racing dog, and the black-and-tan terrier,......
mandrill
mandrill, (Mandrillus sphinx), colourful and primarily ground-dwelling monkey that inhabits the rainforests of......
maned rat
maned rat, (Lophiomys imhausi), a long-haired and bushy-tailed East African rodent that resembles a porcupine and......
maned wolf
maned wolf, (Chrysocyon brachyurus), rare large-eared member of the dog family (Canidae) found in remote plains......
mangabey
mangabey, any of nine species of slender, rather long-limbed monkeys of the genera Cercocebus and Lophocebus, found......
Manx
Manx, breed of tailless domestic cat of unknown origin but presumed by tradition to have come from the Isle of......
mara
mara, either of two South American rodents in the genus Dolichotis of the cavy family, the Patagonian mara (D.......
marbled cat
marbled cat, (species Felis marmorata), rare Southeast Asian cat, family Felidae, often referred to as a miniature......
margay
margay, (Leopardus wiedii), small cat (family Felidae) that ranges from South through Central America and, rarely,......
markhor
markhor, (Capra falconeri), large wild goat of the family Bovidae (order Artiodactyla), formerly found throughout......
marmoset
marmoset, (family Callitrichidae), any of numerous species of small long-tailed South American monkeys. Similar......
marmot
marmot, (genus Marmota), any of 14 species of giant ground squirrels found primarily in North America and Eurasia.......
marten
marten, (genus Martes), any of eight species of weasel-like carnivores of the genus Martes (family Mustelidae),......
Mastiff
Mastiff, breed of large working dog used as a guard and fighting dog in England for more than 2,000 years. Dogs......
mastiff bat
mastiff bat, any of various species of free-tailed bats (family Molossidae) named for their doglike faces. The......
mastodon
mastodon, (genus Mammut), any of several extinct elephantine mammals (family Mammutidae, genus Mammut ) that first......
meadow vole
meadow vole, (Microtus pennsylvanicus), one of the most common and prolific small mammals in North America. Weighing......
Measuring the Reign of Homo naledi
The first remains of Homo naledi were found by cavers in September 2013 in a remote alcove (the Dinaledi Chamber)......
meerkat
meerkat, (Suricata suricatta), burrowing member of the mongoose family (Herpestidae), found in southwestern Africa,......
Megatherium
Megatherium, largest of the ground sloths, an extinct group of mammals belonging to a group containing sloths,......
Merino
Merino, breed of fine-wool sheep originating in Spain; it was known as early as the 12th century and may have been......
Merychippus
Merychippus, extinct genus of early horses, found as fossils in deposits from the Middle and Late Miocene Epoch......
Mesohippus
Mesohippus, genus of extinct early and middle Oligocene horses (the Oligocene Epoch occurred from 33.9 to 23 million......
Mexican hairless
Mexican hairless, breed of dog that is probably descended from hairless Chinese or African dogs that were taken......
Miacis
Miacis, genus of extinct carnivores found as fossils in deposits of the late Paleocene Epoch (65.5–55.8 million......
miner’s cat
miner’s cat, carnivorous mammal, a species of cacomistle...
Miniature Pinscher
Miniature Pinscher, breed of toy dog originating in Germany, perhaps as early as the 1600s. The dog may have been......
mink
mink, either of two species of the weasel family (Mustelidae) native to the Northern Hemisphere. The European mink......
Miohippus
Miohippus, genus of extinct horses that originated in North America during the Late Eocene Epoch (37.2–33.9 million......
Missouri fox-trotting horse
Missouri fox-trotting horse, breed of horse that originated in Missouri and the Ozark Mountains region and is characterized......
Moeritherium
Moeritherium, extinct genus of primitive mammals that represent a very early stage in the evolution of elephants.......
mole
mole, (family Talpidae), any of 42 species of insectivores, most of which are adapted for aggressive burrowing......
mona monkey
mona monkey, (Cercopithecus mona), common West African primate found in tropical rainforests; it was introduced......
mongoose
mongoose, any of nearly three dozen species of small bold predatory carnivores found mainly in Africa but also......
monk seal
monk seal, any of three little-known tropical or subtropical seals of the genus Monachus, family Phocidae. Characterized......
monkey
monkey, in general, any of nearly 200 species of tailed primate, with the exception of lemurs, tarsiers, and lorises.......
moonrat
moonrat, (Echinosorex gymnura), a large Southeast Asian insectivore that is essentially a primitive tropical hedgehog......
moose
moose, (Alces alces), largest member of the deer family Cervidae (order Artiodactyla). Moose are striking in appearance......
Morgan
Morgan, breed of horse that was once the most famous and widely disseminated in the United States. The Morgan declined......
Moropus
Moropus, extinct genus of the chalicotheres, a group of very unusual perissodactyls (“odd-toed” ungulates) related......
mouflon
mouflon, (Ovis aries), small feral sheep (family Bovidae, order Artiodactyla) of Corsica and Sardinia (O. a. musimon)......
mountain beaver
mountain beaver, (Aplodontia rufa), a muskrat-sized burrowing rodent found only in the Pacific Northwest of North......
mountain goat
mountain goat, (Oreamnos americanus), a stocky North American ruminant of the family Bovidae (order Artiodactyla).......
mouse
mouse, (genus Mus), the common name generally but imprecisely applied to rodents found throughout the world with......
mule
mule, the hybrid offspring of a male ass (jackass, or jack) and a female horse (mare). The less-frequent cross......
mule deer
mule deer, (Odocoileus hemionus), a medium-sized, gregarious deer of western North America that derives its name......
muntjac
muntjac, any of about seven species of small- to medium-sized Asiatic deer that make up the genus Muntiacus in......
Muridae
Muridae, (family Muridae), largest extant rodent family, indeed the largest of all mammalian families, encompassing......
Murray Grey
Murray Grey, breed of Australian beef cattle first bred in 1905 in the Murray River valley on the border between......
musk deer
musk deer, (Moschus moschiferus), small compact deer, family Moschidae (order Artiodactyla). A solitary shy animal,......
musk ox
musk ox, (Ovibos moschatus), shaggy-haired Arctic ruminant of the family Bovidae (order Artiodactyla). Musk oxen......
muskrat
muskrat, (Ondatra zibethicus), a large amphibious rodent indigenous to North America but found also in Europe,......
mustelid
mustelid, (family Mustelidae), any of about 62 species of ferrets, polecats, badgers, martens, otters, the wolverine,......
Mylodon
Mylodon, extinct genus of ground sloth found as fossils in South American deposits of the Pleistocene Epoch (2.6......
naked mole rat
naked mole rat, (Heterocephalus glaber), burrowing member of the rodent family Bathyergidae, named for its wrinkled......
narwhal
narwhal, (Monodon monoceros), a small toothed whale found along coasts and in rivers throughout the Arctic. Males......
Neanderthal
Neanderthal, (Homo neanderthalensis, Homo sapiens neanderthalensis), member of a group of archaic humans who emerged......
New Zealand short-tailed bat
New Zealand short-tailed bat, (genus Mystacina), either of two species (M. robusta and M. tuberculata) of small......
Newfoundland
Newfoundland, large breed of working dog developed on Newfoundland island, possibly from crosses between native......
nilgai
nilgai, (Boselaphus tragocamelus), the largest Asian antelope (family Bovidae). The nilgai is indigenous to the......
noctule
noctule, (genus Nyctalus), any of about six species of vesper bats (family Vespertilionidae) found in Europe and......
northern white rhinoceros
northern white rhinoceros, (Ceratotherium simum cottoni), critically endangered subspecies of the white rhinoceros......
Norwegian elkhound
Norwegian elkhound, breed of dog that originated thousands of years ago in western Norway, where it was used as......
Norwegian Forest Cat
Norwegian Forest Cat, a breed of long-haired domestic cat known for its large size, strong, muscular body, and......

Placental Mammals Encyclopedia Articles By Title