Panthera leo (Lion)

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© Photo: Lee R. Berger
Male lion.
Lion
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Family: Felidae
Genus: Panthera
Species: P. leo
Binomial name
Panthera leo
(Linnaeus, 1758)
Synonyms
Felis leo
(Linnaeus, 1758)

The lion is one of the "big cats". Although not as large as the tiger, the lion is known as "the king of beasts". The male lion, easily recognized by his mane, weighs between 150-225 kg (330-500 lb). Females range 120-150 kg (260-330 lb).[1] In the wild, lions live for around 10–14 years, while in captivity they can live over 20 years. Though they were once found throughout much of Africa, Asia and Europe, lions presently exist in the wild only in Africa and India (where they are found only in the Sasan-Gir National Park).

Population and distribution

© Photo: Lee R. Berger
Male lion, Tanzania.

In historic times the habitat of lions spanned the southern parts of Eurasia, ranging from Portugal to India, and most of Africa except the central rain forest-zone and the sahara-desert. Around the beginning of the current era they died out from Western Europe and they had become extinct in Greece by AD 100. In the Caucasus, their last European outpost, lions were found until the 10th century. Between the late 19th century and early 20th century they also became extinct from North Africa and Middle East. Now, most of the population lives in eastern and southern Africa, and their numbers are rapidly decreasing, estimated as between 16,000 and 30,000 living in the wild, down from an estimated 100,000 in the early 1990s. The population is even more in jeopardy, because the remaining populations are often geographically isolated from each other, which causes inbreeding. [1]

The Asiatic Lion (Panthera leo persica), which in historical times ranged from Turkey to India through Iran (Persia) and from Caucasus to Yemen, was eradicated from Palestine by the Middle Ages and from most of the rest of Asia after the arrival of readily available firearms in the 18th century. In Iran the last lion was shot in 1942. The subspecies now survives only in and around the Gir Forest of northwestern India. About 300 lions live in a 1412 km² (558 square miles) sanctuary in the state of Gujarat, which covers most of the forest. Their numbers remain stable.

Until the late pleistocene lions were also found in the Americas and in northern Eurasia. The most famous of these prehistoric subspecies were the European Cave Lion (Panthera leo spelaea) and the American lion (Panthera leo atrox), (not to be confused with the mountain lion or puma).

Habitat

Lions are quite adaptable and can be found in a variety of different habitats like deciduous forests and semideserts but they prefer savannas, grassy plains, open woodlands and scrub country. They are never found in tropical rain forests or true deserts without any water.

The lion is found in parts of Africa south of the Sahara desert. Lions are the most social of all the felids, and live in organized groups called prides which can hold four to forty members. The pride is made up of related lionesses and their cubs and one to six males which have fought their way into the pride. If a lion is killed by another lion trying to join the pride, the previous male's cubs will be killed to give way for the new dominate lion's offspring. When a female comes to realize her cubs are gone, she goes into estrus and mates with the new dominate male. The pride is very social, and they often lick and rub heads with each other. The males are the protectors of the pride, and the females are the hunters and take care of the cubs.

Diet and hunting

Lions usually hunt at night or dawn. Their prey consists mainly of large mammals, such as antelopes, gazelles, warthogs, wildebeest, buffalos and zebras, but smaller animals like hares and birds are also taken occasionally. Carrion is readily taken and often recovered from other predators like hyenas and wild dogs. In some areas lions specialise on rather atypical prey-species; this is the case at the Savuti river, where they constantly prey on young elephants, and at the Linyanti, where they hunt hippos (both rivers are in Chobe National Park, Botswana). It is reported that the lions, driven by extreme hunger, started taking down baby elephants, then moved on to adolescents and occasionally fully grown adults.[2]

Young lions first try hunting at three months old, but are often not successful hunters until they are two years old.

Lions can reach speeds of about 60 km/h (37 mph), but only for brief intervals of maximal effort. Sprinters rather than long-distance runners, they only attack when reasonably close to the prey. Like many cats, they use the ambush as a standard hunting style. Slowly and quietly, they steadily approach the distant victim until a range of about 30 m (98 feet) or less. Unlike some other cats, lions often hunt together in a pack. Several lions (most often lionesses) encircle the herd or a single prey animal, each approaching from a different direction. The actual attack is very fast, the lion coming on in a bounding run and a final leap. The prey is usually dispatched immediately by a bite into the nape of the neck or the undersurface of the throat.

Because lions hunt in open spaces, where they can be easily seen by their prey, teamwork increases the likelihood of a successful hunt. Teamwork also enables them to defend their prey more easily against other large predators like hyenas, often be attracted by sight of vultures circling over the kill, a sight that is visible over kilometers in the open savannas. The males do not usually participate in hunting, except in the case of large animals such as buffalo.

An adult female lion needs about 5 kg (11 lbs) meat per day, a male ca. 7 kg (15 lbs). Lions usually feed off of a large prey animal for several days.

Social behavior: the pride

© Photo: Lee R. Berger
Lions at night in Kruger National Park, South Africa.

Lions are predatory carnivores who manifest two types of social organization. Some are residents, living in groups, called prides. The pride consists of related females, their cubs of both sexes, and a group of one to four males known as a coalition who mate with the adult females. Others are nomads, ranging widely, either singly or in pairs. The lionesses of a pride keep other lionesses out, and the lions repel other males.

Smaller and lighter than males, lionesses are both faster and more agile and do the pride's hunting. The stronger males patrol the territory and protect the pride, for which they take the "lion's share" of the females' prey. Of course, the protective efforts of the male lion are really almost solely directed at other male lions trying to join the pride! When resting, lions seem to enjoy good fellowship with lots of touching, head rubbing, licking and purring. But when it comes to food, each lion looks out for itself. Squabbling and fighting are common, with adult males usually eating first, followed by the females and then the cubs.

Both males and female lions will defend the pride against intruders. Some individual lions consistently lead the defense against intruders, while other lag behind. (Heinsohn and Packer 1995). These “laggards” are not punished by leaders. Possibly laggards provide other services to the group so that leaders" forgive" them (Morrell 1995). An alternative hypothesis is that there is some reward associated with being a leader who fends off intruders (Jahn 1995).

Typically, males will not tolerate outside males, and females will not tolerate outside females. Males are expelled from the pride or leave on their own when they reach maturity.

Lions spend a lot of their time resting. They are inactive for about 20 hours per day.

Reproduction and sexuality

Lions do not have a specific time of year where they mate and the females are polyestrous.

During a mating bout, which could last several days, the couple frequently copulate (twenty to forty times a day) and are likely to forgo hunting. At times the female may couple with other males in the pride, giving rise to the possibility of different cubs in the same litter having different fathers. In captivity, lions reproduce very well and have been propagated in numbers in zoos and wildlife parks.

The gestation lasts between one hundred and one hundred twenty days, and the female gives birth to a litter of one to four cubs. The females in a pride will synchronize their reproductive cycles so that they cooperate in the raising and suckling of the young, who suckle indiscriminately from any or all of the nursing females in the pride. Cubs are weaned after six to seven months. In the wild, competition for food is fierce, and as many as 80% of the cubs will die before the age of two.

When a new male (or a coalition) takes over a pride and ousts the previous master(s), the conquerors often kill any remaining cubs. This is explained by the fact that the females would not become fertile and receptive until the cubs grow up or die. The male lions reach maturity at about 3 years of age and are capable of taking over another pride at 4-5 years old. They begin to age (and thus weaken) at around 8. This leaves a short window for their own offspring to be born and mature — the fathers have to procreate as soon as they take over the pride. Sometimes a female may defend her and the ousted male's children from the new master, but such actions are rarely successful, as he usually kills all the previous top male's cubs that are less than two years old.[3]

Physical characteristics

The male lion, easily recognized by his mane, can weigh between 150-225 kg (330-500 lb), but usually most males average around 186 kg (410 lb) and females range from 120-150 kg (260-330 lb)[4], and average around 125 kg (275 lb). Head and body length is 170 to 250 cm in males and 140 to 175 cm in females, shoulder height is about 123 cm in males and 100 cm in females. The tail length is 70 to 100 cm. [5] In the wild, lions live for around 10–14 years, while in captivity they can live over 20 years.

The coloration varies from light buff to yellowish, reddish or dark ochraceous brown. The underparts are generally brighter and the hairy tuft at the tip of the tail is black. The colour of the manes varies from blond to black.

Manes

The first lions are presumed to have been maneless. Until around 10,000 years ago, maneless forms seem to have persisted in Europe, and possibly the New World. The maned form may have appeared c. 320,000–190,000 years ago. This maned form may have had a selective advantage that enabled it to expand to replace the range of earlier maneless forms throughout Africa and western Eurasia by historic times.[6] The mane has evolved due to sexually selective pressure driving the trait to an exaggerated point where it no longer serves any other function. The trait has reached the point where cost of maintaining the mane has begun to outweigh its benefits. In fact, lions with particularly large manes often have trouble with thermoregulation. [7]

In the past scientists believed that the "distinct" subspecific status of some subspecies could be justified by their external morphology, like the size of their mane. This morphology was used to identify them, like the Barbary lion and Cape lion. However, now it is known that various extrinsic factors influence the colour and size of a lion’s mane, like the ambient temperature.[8] The cooler ambient temperature in e.g. European and North American zoos can result in heavy mane. Therefore, the heavy mane is an inappropriate marker for identifying subspecies.[9][10]

Maneless lions have been reported in Senegal and Tsavo-National Park. As well as having an inherited component, the presence, absence and degree of mane is also associated with sexual maturity and testosterone production. Castrated lions have minimal manes. The original male white lion from Timbavati was also maneless. Manelessness is also found in inbred lion populations; inbreeding also results in poor fertility. A heavy mane may provide an indicator of a lion's genetic and physical health. It may also afford him some protection in fights. In some animal species, females show a preference for males with better outward displays of fertility and vigour. It is possible that lionesses more actively solicit mating with heavily maned lions in prides led by a coalition of 2 or 3 males, though there seem to be no published studies.

Evolution

The oldest fossil record of a lion is known from Laetoli in Tanzania and is perhaps 3.5 million years old. 700,000 years ago Panthera leo appeared in europe for the first time with the subspecies Panthera leo fossilis at Isernia in Italy. From this lion derived the later Cave lion (Panthera leo spelea), which appears about 300,000 years ago. During the upper Pleistocene the lion spread to North- and South-America, and developed here into Panthera leo atrox, the American lion.[11]

Lions were common in northern Eurasia and America during the upper pleistocene, but died out there at the end of the last glaciation, about 10.000 years ago.

Taxonomy

Subspecies

The major differences between lion subspecies are location, mane appearance, size and distribution. However some of the forms listed below are debatable. Genetic evidence suggests that all modern lions derived from one common ancestor only circa 55,000 years ago. Therefore most sub-Saharan lions could be considered a single subspecies Panthera leo leo.

Most scientists today recognise subspecies (not all named here are considered valid by all scientists).[12]

  • Panthera leo azandica - North East Congo lion.
  • Panthera leo bleyenberghi - Katanga lion or Southwest African lion. Zimbabwe, Angola, Katanga (Zaire).
  • Panthera leo europaea - European lion. Status as subspecies is unconfirmed. (Probably identical with Panthera leo persica or Panthera leo spelea) Extinct around 100 due to persecution and over-exploitation, though may have been Panthera leo persica. Inhabited the Balkans, the Italian Peninsula, southern France and the Iberian Peninsula. It was a very popular object of hunting among Romans, Greeks and Macedonians.
  • Panthera leo hollisteri - Congo lion.
  • Panthera leo krugeri - South African lion or Southeast African lion. Transvaal.
  • Panthera leo leo (P. l. berberisca) - Barbary lion; extinct at least in the wild and was believed to be extinct in captivity. This was the largest of the lion subspecies, which ranged from Morocco to Egypt. The last wild Barbary lion was killed in Morocco in 1922 due to excessive hunting. Barbary lions were kept by Roman emperors to take part in the gladiator arenas. Roman notables, including Sulla, Pompey, and Julius Caesar, often ordered the mass slaughter of Barbary lions - up to 400 at a time. [2]
  • Panthera leo melanochaita - Cape lion; extinct in 1860.
  • Panthera leo massaicus - Massai lion.
  • Panthera leo nubica - East African lion.
  • Panthera leo persica - Asiatic lion or South Asian lion. 350 currently exist in and near the Gir Forest of India. Once widespread from Turkey, across the Middle East, to Pakistan, India and even Bangladesh, but large prides and daylight activity made it easier to poach than tigers or leopards.
  • Panthera leo roosevelti - Abyssinian lion.
  • Panthera leo somaliensis - Somali lion.
  • Panthera leo senegalensis - West African lion, or Senegal lion. Western Africa.
  • Panthera leo verneyi - Kalahari lion. Distinct behaviour and anatomy has been observed in this subspecies.

Besides these subspecies there are also some prehistoric ones. [13]

The Marozi, a spotted lion, is sometimes believed to be a distinct subspecies (Panthera leo maculatus) Thought to be extinct since 1931. May have been a natural leopard/lion hybrid.

Variations

A number of natural variations have been observed in the lion populations. Some of these have been encouraged by captive breeding.

White lions

Although rare, white lions are occasionally encountered in Timbavati, South Africa. Their unusual color is due to a recessive gene. A white lion has a disadvantage when it comes to hunting: it can be given away by its color, unlike the regular lion which blends in with its surroundings. White lions are born almost pure white without the normal camouflaging spots seen in lion cubs. Their colour gradually darkens to cream or ivory colour (known as blonde).

Cross-breeding lions with other big cat species

Lions have also been known to breed with tigers (most often Amur and Bengal) to create hybrids called ligers and tigons. They have also been crossed with leopards to produce leopons and jaguars to produce jaglions. The marozi is reputedly a spotted lion or a naturally occurring leopon, while the Congolese spotted lion is a complex lion/jaguar/leopard hybrid called a lijagulep. Such hybrids were once commonly bred in zoos, but this is now discouraged due to the emphasis on conserving species and subspecies. Hybrids are still bred in private menageries and in zoos in China.

The liger is a cross between a male lion and a tigress. Because the lion sire passes on a growth-promoting gene, but the corresponding growth-inhibiting gene from the female lion is absent, ligers grow larger than either parent. They share physical and behavioural qualities of both parent species (spots and stripes on a sandy background). Male ligers are sterile, but female ligers are often fertile.

The less common tigon is a cross between the lioness and the male tiger. Because the male tiger does not pass on a growth-promoting gene and the lioness passes on a growth inhibiting gene, tigons are often relatively small, only weighing up to 150 kilograms (350 lb), which is about 20% smaller than lions. Like ligers, they have physical and behavioural traits from both parental species and males are sterile.

Attacks on humans

While a hungry lion may occasionally attack a human that passes near, some (usually male) lions seem to seek out human prey. Some of the more publicized cases include the Tsavo maneaters and the Mfuwe man-eater. In both cases the hunters who killed the lions wrote books detailing the lions' "careers" as man-eaters. In folklore, man-eating lions are sometimes considered demons.

The Mfuwe and Tsavo incidents did bear some similarities. The lions in both the incidents were all larger than normal, lacked manes and seemed to suffer from tooth decay. Some have speculated that they might belong to an unclassified species of lion, or that they may have been sick and could not have easily caught prey.

There have also been recorded attacks on humans by lions in captivity; although tigers in captivity are statistically much more likely to attack humans. Wild lions are also much less likely to attack humans than wild tigers are.

Also, Professor Craig Packer of the University of Minnesota and Tanzanian scientist Dennis Ikanda authored an important paper in "Nature" in 2006 that showed man-eating behavior in rural areas of Tanzania had increased greatly from 1990 through 2005. More than 500 villagers were attacked and many eaten in this time period -- a number far exceeding the more famed "Tsavo" incidents of a century and more earlier. The problem, near Selous National Park in Rufijji Province and in Lindi Province near the Mozambican border. While some of these problems are no doubt caused by the expansion of villagers into bush country, the authors argue that conservation policy must mitigate the problem because conservation policies contribute directly to human deaths. Cases in Lindi have been documented where lions seize humans form the center of substantial villages.

Author Robert R. Frump also wrote in 2006 that Mozambican refugees crossing Kruger National Park at night in South Africa regularly are attacked and eaten by the lions there. Park officials conceded that man-eating is a problem there. Frump believes thousands may have been killed in the decades after apartheid sealed the park and forced the refugees to cross the park at night. Mozambicans had for nearly a century before the border was sealed regularly walked across the park in daytime with little harm. (See www.man-eater.info)

Packer estimates more than 200 Tanzanians are killed each year by lions, crocodiles, elephants, hippos and snakes, and that the numbers could be double that amount. Lions are thought to kill about 70 humans per year at least in Tanzania, Packer and Ikanda note. Packer and Ikanda are among the few conservations who believe western conservation efforts must take account of these matters not just because of ethical concerns about human life but for the long term success of conservation efforts and lion preservations.

The "All-Africa" record of man-eating generally is considered to be not Tsavo but the lesser known incidents in the late 1930's through the late 1940's in what was then Tanganyika (now Tanzania.) George Rushby, game warden and professional hunter, eventually dispatched the pride, which over 3 generations, is thought to have killed and eaten 1,500 to 2,000.

Tsavo and Patterson body counts vary from a pretty firm 28 up to 140. While some authors disparage the actual number, it should be kept in mind that Patterson kept firm records of skilled-labor killed by the lions, not indigenous Africans. The toll could easily have been much higher.

Footnotes

  1. BBC - Science & Nature - Wildfacts - Lion. Retrieved on 2006-10-24.
  2. Power, R. John (April 2009). Lion Predation on Elephants in the Savuti, Chobe National Park, Botswana. African Zoology. ResearchGate. Retrieved on 11 October 2013.
  3. Honolulu Zoo lion information page
  4. BBC Wildfacts – Lion.
  5. Ronald M. Nowak: Walker's Mammals of the World. Johns Hopkins University Press, 1999 ISBN 0801857899
  6. Yamaguchi, N., A. Cooper, L. Werdelin & D.W. Macdonald. 2004. Evolution of the mane and group-living in the lion (Panthera leo): a review. Journal of Zoology, 263: 329-342 Cambridge University Press
  7. Simandle, E. T. & C. R. Tracy. 2003. The main question: Untangling why lions have it. SICB Annual Meeting & Exhibition Final Program and Abstracts 2003.
  8. West P.M., Packer C. 2002. Sexual selection, temperature, and the lion’s mane. Science, 297, 1339–1343.
  9. Barnett, R., N. Yamaguchi, I. Barnes & A. Cooper. 2006. Lost populations and preserving genetic diversity in the lion Panthera leo: Implications for its ex situ conservation. Conservation Genetics. Online full-text pdf
  10. Yamaguchi, N. & Haddane, B. (2002). The North African Barbary lion and the Atlas Lion Project. International Zoo News 49: 465-481.
  11. A. Turner: The big cats and their fossil relatives. Columbia University Press, 1997.ISBN 0-231-10229-1
  12. Barnett, R., N. Yamaguchi, I. Barnes & A. Cooper. 2006. Lost populations and preserving genetic diversity in the lion Panthera leo: Implications for its ex situ conservation. Conservation Genetics. Online pdf
  13. Burger J, Rosendahl W, Loreille O, Hemmer H, Eriksson T, Götherström A, Hiller J, Collins MJ, Wess T, Alt KW. (2004). Molecular phylogeny of the extinct cave lion Panthera leo spelaea. Mol. Phylogenet. Evol., 30, 841–849. Online pdf
  14. Burger J, Rosendahl W, Loreille O, Hemmer H, Eriksson T, Götherström A, Hiller J, Collins MJ, Wess T, Alt KW. (2004). Molecular phylogeny of the extinct cave lion Panthera leo spelaea. Mol. Phylogenet. Evol., 30, 841–849. Online pdf