Physical characteristics
The lion is the tallest (at the shoulder) of the felines, and also is the second-heaviest feline after the tiger. With powerful legs, a strong jaw, and 8 cm (3.1 in) long canine teeth, the lion can bring down and kill large prey. The skull of the lion is very similar to that of the tiger, though 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.[38] 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 specialized roles that each gender plays in the pride. For instance, the lioness, the hunter, lacks the male's thick cumbersome mane. It seems to impede the male's ability to be camouflaged when stalking the prey and create overheating in chases. The color of the male's mane varies from blond to black, generally becoming darker as the lion grows older.
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 for males and 126 kg for females; one male shot near Mount Kenya was weighed at 272 kg (600 lb). 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 about 123 cm (4 ft) in males and 107 cm (3 ft 6 in) 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). The longest known lion was a black-maned male shot near Mucsso, southern Angola in October 1973; the heaviest known lion was a man-eater shot in 1936 just outside Hectorspruit in eastern Transvaal, South Africa and weighed 313 kg (690 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).
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.
Mane
The mane of the adult male lion, unique among cats, is one of the most distinctive characteristics of the species. It makes the lion appear larger, providing an excellent intimidation display; this aids the lion during confrontations with other lions and with the species' chief competitor in Africa, the spotted hyena. The presence, absence, color, and size of the mane is associated with genetic precondition, sexual maturity, climate, and testosterone production; the rule of thumb is the darker and fuller the mane, the healthier the lion. Sexual selection of mates by lionesses favors males with the densest, darkest mane. Research in Tanzania also suggests mane length signals fighting success in male-male relationships. Darker-maned individuals may have longer reproductive lives and higher offspring survival, although they suffer in the hottest months of the year.[45] In prides including a coalition of two or three males, it is possible that lionesses solicit mating more actively with the males who are more heavily maned.
Scientists once believed that the distinct status of some subspecies could be justified by morphology, including the size of the mane. Morphology was used to identify subspecies such as the Barbary Lion and Cape Lion. Research has suggested, however, that environmental factors influence the color and size of a lion's mane, such as the ambient temperature. The cooler ambient temperature in European and North American zoos, for example, may result in a heavier mane. Thus the mane is not an appropriate marker for identifying subspecies. The males of the Asiatic subspecies, however, are characterized by sparser manes than average African lions.
Maneless male lions have been reported in Senegal and Tsavo East National Park in Kenya, and the original male white lion from Timbavati also was maneless. Castrated lions have minimal manes. The lack of a mane sometimes is found in inbred lion populations; inbreeding also results in poor fertility.