American lion
Encyclopedia
The American lion — also known as the North American lion, Naegele’s giant jaguar or American cave lion
Cave lion
Panthera leo spelaea also known as the European or Eurasian cave lion, is an extinct subspecies of lion known from fossils and many examples of prehistoric art.-Physical characteristics:This subspecies was one of the largest lions...

— is an extinct lion
Lion
The lion is one of the four big cats in the genus Panthera, and a member of the family Felidae. With some males exceeding 250 kg in weight, it is the second-largest living cat after the tiger...

 of the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Felidae
Felidae
Felidae is the biological family of the cats; a member of this family is called a felid. Felids are the strictest carnivores of the thirteen terrestrial families in the order Carnivora, although the three families of marine mammals comprising the superfamily pinnipedia are as carnivorous as the...

, endemic to North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

 during the Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....

 epoch (0.34 mya to 11,000 years ago), existing for approximately . It has been shown by genetic analysis to be a sister lineage to the Eurasian cave lion (Panthera leo spelaea).

The American lion was one of the largest types of cat ever to have existed, slightly larger than the Early Middle Pleistocene primitive cave lion, P. leo fossilis
Panthera leo fossilis
Panthera leo fossilis, also known as the Early Middle Pleistocene European cave lion, is an extinct feline of the Pleistocene epoch. It is generally considered to be an early subspecies of the lion ....

and about twenty-five percent larger than the modern African lion.

Description

The American lion is an extinct animal which originated in North America and went on to colonize part of South America as part of the Great American Interchange
Great American Interchange
The Great American Interchange was an important paleozoogeographic event in which land and freshwater fauna migrated from North America via Central America to South America and vice versa, as the volcanic Isthmus of Panama rose up from the sea floor and bridged the formerly separated continents...

. The head-body length of the American lion is estimated to have been 1.6 metre and it would have stood 1.2 metres (4 ft) at the shoulder. Thus it was smaller than its contemporary competitor for prey, the giant short-faced bear, which was the largest carnivora
Carnivora
The diverse order Carnivora |Latin]] carō "flesh", + vorāre "to devour") includes over 260 species of placental mammals. Its members are formally referred to as carnivorans, while the word "carnivore" can refer to any meat-eating animal...

n of North America at the time. The American lion was not as heavily built as the saber-toothed cat Smilodon populator, which may have weighed up to 360–470 kg (793.7–1,036.2 lb). Sorkin (2008) estimated it to weigh roughly 420 kilograms (925.9 lb), but new estimations show a top weight of 351 kg (774lbs.) for the largest specimen and an average weight for males of 255.65 kg (563lbs.).

Approximately one hundred specimens of American lions have been recovered from the La Brea Tar Pits
La Brea Tar Pits
The La Brea Tar Pits are a cluster of tar pits around which Hancock Park was formed, in the urban heart of Los Angeles. Asphaltum or tar has seeped up from the ground in this area for tens of thousands of years. The tar is often covered with water...

, in Los Angeles
Los Ángeles
Los Ángeles is the capital of the province of Biobío, in the commune of the same name, in Region VIII , in the center-south of Chile. It is located between the Laja and Biobío rivers. The population is 123,445 inhabitants...

, so their body structure is well known. The features and teeth of the extinct American lion strongly resemble modern lions, but they were considerably larger. The American lion was once believed to be the largest subspecies of lion.

Range

South of Alaska, the American lion first appeared during the Sangamonian Stage
Sangamonian Stage
The Sangamonian Stage, also known as the Sangamon interglacial, is the name used by Quaternary geologists to designate the last interglacial period in North America from 125,000—75,000 years ago, a period of...

 (the last interglacial
Interglacial
An Interglacial period is a geological interval of warmer global average temperature lasting thousands of years that separates consecutive glacial periods within an ice age...

). After that it was widespread in the western Americas from Alaska to Peru. It was absent from most of eastern North America and peninsular Florida, although it may have been present in the Lake Michigan
Lake Michigan
Lake Michigan is one of the five Great Lakes of North America and the only one located entirely within the United States. It is the second largest of the Great Lakes by volume and the third largest by surface area, after Lake Superior and Lake Huron...

 area. Like many other large mammals, it went extinct at the end of the Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....

, about 10,000 years ago. By then the American lion was one of the abundant Pleistocene megafauna
Pleistocene megafauna
Pleistocene megafauna is the set of species of large animals — mammals, birds and reptiles — that lived on Earth during the Pleistocene epoch and became extinct in a Quaternary extinction event. These species appear to have died off as humans expanded out of Africa and southern Asia,...

, a wide variety of very large mammals who lived during the Pleistocene. Remains are most common in the Yukon
Yukon
Yukon is the westernmost and smallest of Canada's three federal territories. It was named after the Yukon River. The word Yukon means "Great River" in Gwich’in....

 and from the La Brea Tar Pits
La Brea Tar Pits
The La Brea Tar Pits are a cluster of tar pits around which Hancock Park was formed, in the urban heart of Los Angeles. Asphaltum or tar has seeped up from the ground in this area for tens of thousands of years. The tar is often covered with water...

.

Environment

In some areas of its range, the American lion lived under cold climatic conditions. They probably used cave
Cave
A cave or cavern is a natural underground space large enough for a human to enter. The term applies to natural cavities some part of which is in total darkness. The word cave also includes smaller spaces like rock shelters, sea caves, and grottos.Speleology is the science of exploration and study...

s or fissures for shelter from the cold weather. They may have lined their dens with grass or leaves, as the Siberian tiger does, another great cat that currently lives in the north.

There are fewer American lions in the La Brea tar pits than other predators such as saber-toothed cat
Saber-toothed cat
Saber-toothed cat or Sabre-toothed cat refers to the extinct subfamilies of Machairodontinae , Barbourofelidae , and Nimravidae as well as two families related to marsupials that were found worldwide from the Eocene Epoch to the end of the Pleistocene Epoch ,...

s (Smilodon fatalis) or dire wolves
Dire Wolf
The Dire Wolf, Canis dirus, is an extinct carnivorous mammal of the genus Canis, and was most common in North America and South America from the Irvingtonian stage to the Rancholabrean stage of the Pleistocene epoch living 1.80 Ma – 10,000 years ago, existing for approximately .- Relationships...

 (Canis dirus), which suggests they may have been smart enough to avoid the hazard. American lions likely preyed on deer
Deer
Deer are the ruminant mammals forming the family Cervidae. Species in the Cervidae family include white-tailed deer, elk, moose, red deer, reindeer, fallow deer, roe deer and chital. Male deer of all species and female reindeer grow and shed new antlers each year...

, North American horses (now extinct), North American camels
Camelops
Camelops is an extinct genus of camels that once roamed western North America, where it disappeared at the end of the Pleistocene about 10,000 years ago. Its name is derived from the Greek κάμελος + , thus "camel-face."-Background:...

, North American tapirs
California tapirs
The California tapir is a term that is applied to either of two species of tapirs that concurrently inhabited the North American continent during the Pleistocene era – Tapirus californicus and Tapirus merriami. Both species went extinct approximately 13,000 to 11,000 B.C...

, American bison
American Bison
The American bison , also commonly known as the American buffalo, is a North American species of bison that once roamed the grasslands of North America in massive herds...

, mammoth
Mammoth
A mammoth is any species of the extinct genus Mammuthus. These proboscideans are members of Elephantidae, the family of elephants and mammoths, and close relatives of modern elephants. They were often equipped with long curved tusks and, in northern species, a covering of long hair...

s, and other large, herbivorous animals.

This species disappeared about the same time as other species during the Holocene extinction event
Holocene extinction event
The Holocene extinction refers to the extinction of species during the present Holocene epoch . The large number of extinctions span numerous families of plants and animals including mammals, birds, amphibians, reptiles and arthropods; a sizeable fraction of these extinctions are occurring in the...

, which wiped out likely prey of megafauna
Megafauna
In terrestrial zoology, megafauna are "giant", "very large" or "large" animals. The most common thresholds used are or...

. Bones of the lion have been found in the trash heaps of Paleolithic
Paleolithic
The Paleolithic Age, Era or Period, is a prehistoric period of human history distinguished by the development of the most primitive stone tools discovered , and covers roughly 99% of human technological prehistory...

 American Indians
Indigenous peoples of the Americas
The indigenous peoples of the Americas are the pre-Columbian inhabitants of North and South America, their descendants and other ethnic groups who are identified with those peoples. Indigenous peoples are known in Canada as Aboriginal peoples, and in the United States as Native Americans...

, so human predation may have contributed to their extinction.

A replica of the jaw of the first specimen of American lion discovered can be seen in the hand of a statue of paleontologist Joseph Leidy
Joseph Leidy
Joseph Leidy was an American paleontologist.Leidy was professor of anatomy at the University of Pennsylvania, and later was a professor of natural history at Swarthmore College. His book Extinct Fauna of Dakota and Nebraska contained many species not previously described and many previously...

, which is currently standing outside the Academy of Natural Sciences
Academy of Natural Sciences
The Academy of Natural Sciences of Drexel University, formerly Academy of Natural Sciences of Philadelphia, is the oldest natural science research institution and museum in the New World...

 in Philadelphia.

Classification

The American lion was initially considered a distinct species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of Pantherinae
Pantherinae
Pantherinae is the subfamily of the family Felidae, which includes the genera Panthera, Uncia and Neofelis.The divergence of Pantherinae from Felinae has been ranked between six and ten million years ago. DNA analysis suggests that the snow leopard Uncia uncia is basal to the entire Pantherinae and...

, with the scientific name Panthera atrox (icon), which means "cruel" or "fearsome panther" in Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...

). Overall the skull of the extinct cat was most like that of the jaguar (P. onca). Some later authors accepted this view, but other experts considered P. l. atrox most closely related to the African lion (P. leo) and its extinct Eurasian relative, the cave lion (P. l. spelaea). Later paleontologists assigned the extinct American cat as a subspecies of P. leo, ("P. leo atrox") rather than as a separate species. At least one authority considers the American lion (along with its closest relative, P. l. spelaea), to be more closely related to the tiger
Tiger
The tiger is the largest cat species, reaching a total body length of up to and weighing up to . Their most recognizable feature is a pattern of dark vertical stripes on reddish-orange fur with lighter underparts...

, P. tigris, citing a comparison of skull
Skull
The skull is a bony structure in the head of many animals that supports the structures of the face and forms a cavity for the brain.The skull is composed of two parts: the cranium and the mandible. A skull without a mandible is only a cranium. Animals that have skulls are called craniates...

 shapes; The braincase, in particular, appears to be especially similar to the braincase of a tiger.
Cladistic studies using morphological characteristics have been unable to resolve the phylogenetic position of the American lion. In the first study, the American lion was grouped with a clade consisting of the extant lion
Lion
The lion is one of the four big cats in the genus Panthera, and a member of the family Felidae. With some males exceeding 250 kg in weight, it is the second-largest living cat after the tiger...

 and the leopard
Leopard
The leopard , Panthera pardus, is a member of the Felidae family and the smallest of the four "big cats" in the genus Panthera, the other three being the tiger, lion, and jaguar. The leopard was once distributed across eastern and southern Asia and Africa, from Siberia to South Africa, but its...

. This result was contradicted by the second study that compared the skull, jaw, and teeth of P. l. atrox with other pantherines and concluded it was not a lion and was distinct from all extant species. The authors suggested that P. l. atrox may have arisen from pantherines that migrated into North America in the mid-Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....

 epoch and also gave rise to jaguars.

However, mitochondrial DNA
Mitochondrial DNA
Mitochondrial DNA is the DNA located in organelles called mitochondria, structures within eukaryotic cells that convert the chemical energy from food into a form that cells can use, adenosine triphosphate...

 sequence data from remains of P. l. atrox from Wyoming
Wyoming
Wyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High...

 and Alberta
Alberta
Alberta is a province of Canada. It had an estimated population of 3.7 million in 2010 making it the most populous of Canada's three prairie provinces...

 shows that the American lion is a sister lineage to P. l. spelaea, and likely arose when an early P. l. spelaea population became isolated south of the North American continental ice sheet
Cordilleran Ice Sheet
The Cordilleran ice sheet was a major ice sheet that covered, during glacial periods of the Quaternary, a large area of North America. This included the following areas:*Western Montana*The Idaho Panhandle...

 about 340 000 years ago. (In the same study, Eurasian and Beringian cave lions were found to be genetically indistinguishable.)

See also

  • Panthera leo vereshchagini
    Panthera leo vereshchagini
    Panthera leo vereshchagini, known as the East Siberian- or Beringian cave lion is an extinct prehistoric lion that inhabited Yakutia , Alaska , and the Yukon Territory during the Pleistocene epoch. Analysis of skulls and mandibles of this lion suggest that it is a new subspecies different from the...

    , the East Siberian or Beringian cave lion.

External links

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