Lion

The lion (Panthera leo) is one of the four big cats in the genus Panthera, and a member of the family Felidae. With some males exceeding 250 kg (550 lb) in weight, it is the second-largest living cat after the tiger. Wild lions currently exist in sub-Saharan Africa and in Asia, with an endangered remnant population in Gir Forest National Park in India, having disappeared from North Africa and Southwest Asia in historic times. Until the late Pleistocene, about 10,000 years ago, the lion was the most widespread large land mammal after humans. They were found in most of Africa, across Eurasia from western Europe to India, and in the Americas from the Yukon to Peru. The lion is a vulnerable species, having seen a major population decline of 30–50% over the past two decades[date missing] in its African range. Lion populations are untenable outside designated reserves and national parks. Although the cause of the decline is not fully understood, habitat loss and conflicts with humans are currently the greatest causes of concern. Within Africa, the West African lion population is particularly endangered.

Lions live for 10–14 years in the wild, while in captivity they can live longer than 20 years. In the wild, males seldom live longer than 10 years, as injuries sustained from continual fighting with rival males greatly reduce their longevity. They typically inhabit savanna and grassland, although they may take to bush and forest. Lions are unusually social compared to other cats. A pride of lions consists of related females and offspring and a small number of adult males. Groups of female lions typically hunt together, preying mostly on large ungulates. Lions are apex and keystone predators, although they scavenge as opportunity allows. While lions do not typically hunt humans, some have been known to do so. Sleeping mainly during the day, lions are primarily nocturnal, although bordering on crepuscular in nature.

Highly distinctive, the male lion is easily recognised by its mane, and its face is one of the most widely recognised animal symbols in human culture. Depictions have existed from the Upper Paleolithic period, with carvings and paintings from the Lascaux and Chauvet Caves, through virtually all ancient and medieval cultures where they once occurred. It has been extensively depicted in sculptures, in paintings, on national flags, and in contemporary films and literature. Lions have been kept in menageries since the time of the Roman Empire, and have been a key species sought for exhibition in zoos over the world since the late 18th century. Zoos are cooperating worldwide in breeding programs for the endangered Asiatic subspecies.

Etymology
The lion's name, similar in many Romance languages, is derived from the Latin leo; and the Ancient Greek λέων (leon). The Hebrew word לָבִיא (lavi) may also be related. It was one of the many species originally described by Linnaeus, who gave it the name Felis leo, in his 18th-century work, Systema Naturae.

Taxonomy and evolution
The lion's closest relatives are the other species of the genus Panthera: the tiger, the jaguar, and the leopard. P. leo evolved in Africa between 1 million and 800,000 years ago, before spreading throughout the Holarctic region. It appeared in the fossil record in Europe for the first time 700,000 years ago with the subspecies Panthera leo fossilis at Isernia in Italy. From this lion derived the later cave lion (Panthera leo spelaea), which appeared about 300,000 years ago. Lions died out in northern Eurasia at the end of the last glaciation, about 10,000 years ago; this may have been secondary to the extinction of Pleistocene megafauna.

Subspecies


Traditionally, 12 recent subspecies of lion were recognised, distinguished by mane appearance, size, and distribution. Because these characteristics are very insignificant and show a high individual variability, most of these forms were probably not true subspecies, especially as they were often based upon zoo material of unknown origin that may have had "striking, but abnormal" morphological characteristics. Today, only eight subspecies are usually accepted, although one of these, the Cape lion, formerly described as Panthera leo melanochaita, probably is invalid. Even the remaining seven subspecies might be too many. While the status of the Asiatic lion (P. l. persica) as a subspecies is generally accepted, the systematic relationships among African lions are still not completely resolved. Mitochondrial variation in living African lions seemed to be modest according to some newer studies, therefore all sub-Saharan lions sometimes have been considered a single subspecies. However, a recent study revealed lions from western and central Africa differ genetically from lions of southern or eastern Africa. According to this study, Western African lions are more closely related to Asian lions than to South or East African lions. These findings might be explained by a late Pleistocene extinction event of lions in western and central Africa and a subsequent recolonisation of these parts from Asia. Previous studies, which were focused mainly on lions from eastern and southern parts of Africa, already showed these can be possibly divided in two main clades: one to the west of the Great Rift Valley and the other to the east. Lions from Tsavo in eastern Kenya are much closer genetically to lions in Transvaal (South Africa), than to those in the Aberdare Range in western Kenya. Another study revealed there are three major types of lions, one North African–Asian, one southern African and one middle African. Conversely, Per Christiansen found that using skull morphology allowed him to identify the subspecies krugeri, nubica, persica, and senegalensis, while there was overlap between bleyenberghi with senegalensis and krugeri. The Asiatic lion persica was the most distinctive, and the Cape lion had characteristics allying it more with P. l. persica than the other sub-Saharan lions. He had analysed 58 lion skulls in three European museums.[21] By far most lions, which are kept in zoos are hybrids of different subspecies. About 77% of the captive lions registered by the International Species Information System are of unknown origin. Nonetheless, they might carry genes, which are extinct in the wild and might be therefore important to maintain overall genetic variability of the lion. It is believed, that those lions, which were imported to Europe until the middle of the 19th century, were mainly Barbary lions from North Africa or lions from the Cape.

Characteristics


A skeletal mount of an African Lion attacking a Common Eland on display at The Museum of Osteology, Oklahoma City, Oklahoma The lion is the tallest (at the shoulder) of all living cats, averaging about 14 cm (5.5 in) taller than the tiger. Behind only the tiger, the lion is the second largest living felid in length and weight. Its skull is very similar to that of the tiger, although the frontal region is usually more depressed and flattened, with a slightly shorter postorbital region. The lion's skull has broader nasal openings than the tiger. However, due to the amount of skull variation in the two species, usually, only the structure of the lower jaw can be used as a reliable indicator of species. Lion coloration varies from light buff to yellowish, reddish, or dark ochraceous brown. The underparts are generally lighter and the tail tuft is black. Lion cubs are born with brown rosettes (spots) on their body, rather like those of a leopard. Although these fade as lions reach adulthood, faint spots often may still be seen on the legs and underparts, particularly on lionesses.

Lions are the only members of the cat family to display obvious sexual dimorphism—that is, males and females look distinctly different. They also have specialised roles that each gender plays in the pride. For instance, the lioness, the hunter, lacks the male's thick mane. The colour of the male's mane varies from blond to black, generally becoming darker as the lion grows older.

During confrontations with others, the mane makes the lion look larger. Weights for adult lions range between 150–250 kg (330–550 lb) for males and 120–182 kg (264–400 lb) for females. Nowell and Jackson report average weights of 181 kg (400 lb) for males and 126 kg (280 lb) for females. Lions tend to vary in size depending on their environment and area, resulting in a wide spread in recorded weights. For instance, lions in southern Africa tend to be about 5 percent heavier than those in East Africa, in general.

Head and body length is 170–250 cm (5 ft 7 in – 8 ft 2 in) in males and 140–175 cm (4 ft 7 in – 5 ft 9 in) in females; shoulder height is up to 123 cm (4 ft) in males and as low as 91 cm (3 ft) in females. The tail length is 90–105 cm (2 ft 11 in - 3 ft 5 in) in males and 70–100 cm in females (2 ft 4 in – 3 ft 3 in).[4] The longest known lion, at nearly 3.6 m (12 ft) in total length, was a black-maned male shot near Mucsso, southern Angola in October 1973; the heaviest lion known in the wild was a man-eater shot in 1936 just outside Hectorspruit in eastern Transvaal, South Africa and weighed 313 kg (690 lb). Another notably outsized male lion, which was shot near Mount Kenya, weighed in at 272 kg (600 lb). Lions in captivity tend to be larger than lions in the wild—the heaviest lion on record is a male at Colchester Zoo in England named Simba in 1970, which weighed 375 kg (826 lb).[48] However, the frequently cited maximum head and body length of 250 cm (8 ft 2 in) fits rather to extinct Pleistocene forms, like the American lion, with even large modern lions measuring several centimeters less in length.

The most distinctive characteristic shared by both females and males is that the tail ends in a hairy tuft. In some lions, the tuft conceals a hard "spine" or "spur", approximately 5 mm long, formed of the final sections of tail bone fused together. The lion is the only felid to have a tufted tail—the function of the tuft and spine are unknown. Absent at birth, the tuft develops around 5½ months of age and is readily identifiable at 7 months.