Friday 05 October
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Kingdom | Animalia |
Phylum | Chordata |
Class | Mammalia |
Order | Cetartiodactyla |
Family | Giraffidae |
Genus | Giraffa (1) |
Spectacularly tall, the giraffe (Giraffa camelopardalis) has a very long neck with a short, upstanding mane, and high shoulders that slope steeply to the hindquarters. The legs are also long. The giraffe’s neck is made up of the same number of neck bones (vertebrae) as most mammals, including humans, but they are much larger and linked by ball and socket joints for improved flexibility (5). The specific name of the giraffe comes from the Latin ‘camelopardalis’, meaning ‘camel marked like a leopard’, owing to their buff background with brown blotches, which helps to camouflage them in the dappled light and shade patterns created by the trees they feed on (7).
The various subspecies of giraffe differ slightly in colouration and patterning. The reticulated giraffe of northeastern Kenya (Giraffa camelopardalis reticulata) has large, chestnut-coloured patches outlined by thin white lines. Rothschild’s giraffe of western Kenya and eastern Uganda (Giraffa camelopardalis rothschildi) has broader dividing white lines than the reticulated giraffe, and no spotting beneath the knees. The Masai giraffe of Tanzania and southern Kenya (Giraffa camelopardalis tippelskirchi) has irregular star-shaped light to dark brown spots. Giraffes have two horn-like structures about 13 centimetres long made of skin-covered bone; they are thin and tufted in females and thick and bald on top in males, as a result of wearing during fights with other males (3). Males can develop calcium depositions on their heads in addition to their horns as they age. These help to deliver heavier blows during fights with other males (3).
The giraffe is non-territorial and sociable, forming loose herds with no permanent members in very variable home ranges of between 5 and 650 square kilometres (3). Females tend to associate most with one another when they have young, as the calves tend to play together in crèches (3). Males leave their mothers at around three years, and sometimes form roaming bachelor herds that look for females (cows) in heat (3). Males spar with each other at all ages, standing side by side and swinging their necks to thump their head into the other male’s body. These fights can be quite gentle, or quite fierce, sometimes resulting in knocked-out giraffes (2). Mating occurs year-round, peaking in the rainy season, and results in pregnancies lasting 15 months. Females will usually become pregnant for the first time in their fourth year (3). The single calf begins life with a two metre drop, as females give birth standing up (8). The newborn calf is able to stand within 20 minutes and will grow about 2.1 metres in its first year. At a year old, young giraffes have been weaned but remain close to the female until at least 22 months old, often remaining nearby for life (3). Despite the females’ attempts to stand over their calves during attacks by lions, spotted hyenas, leopards and African wild dogs (4), many calves are killed in their first few months (3). Sexual maturity occurs at three to four years in both males and females, but males rarely have the opportunity to mate before seven years old (3). Life expectancy in the wild is 20 years (4).
Using its 45 centimetre prehensile, black tongue, the giraffe rips the thorny leaves from Acacia and Combretum trees and may eat as many as 100 other plant species (3). Reaching higher than any other mammal, the giraffe can eat up to 134 kilograms of leaves a day, and can ruminate whilst walking (3). These enormous animals do not migrate as they can obtain most of the moisture they need from their diet, but they will drink every two to three days when water is available. It is possible to distinguish the sexes from a distance as males more often extend their heads in line with their necks to reach branches higher than those the females are feeding from, with bent necks (5).
With strong eyesight from an elevated position and a good sense of smell, giraffes are often accompanied by zebra and wildebeest which may benefit from the giraffe as an ‘early warning system’ (6). Whilst it was thought that giraffes did not make any sounds, this is now known to be untrue, as giraffes bellow, snort, hiss and make flute-like sounds, as well as low pitch noises beyond the range of human hearing (3).
The giraffe is classified as Vulnerable (VU) on the IUCN Red List (1). Subspecies: Niger giraffe Giraffa camelopardalis peralta and Rothschild’s giraffe Giraffa camelopardalis rothschildi are classified as Endangered on the IUCN Red List (1).
Giraffes are protected where they occur in National Parks and private game parks, and whilst they are also protected by hunting laws, poaching still occurs (5). The giraffe is involved in a Species Survival Program for captive individuals in American zoos, which includes the education of the public in conservation matters as well as cooperation with other conservation agencies (10).
Learn more about the giraffe and its conservation:
Authenticated by Professor Anne Innis Dagg, University of Waterloo, Canada.
Image credit
© Thomas Dressler / www.ardea.com
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