Giraffe (Giraffa camelopardalis)
The Giraffe is an even-toed ungulate mammal, the tallest of all land-living animal species. Males can be 4.8 to 5.5 metres (16 to 18 feet) tall and weigh up to 900 kilograms (2000 pounds). Females are generally slightly shorter and weigh less.
Native to Africa, the Giraffe is related to deer and cattle, but is placed in a separate family, the Giraffidae, consisting only of the giraffe and its closest relative, the Okapi.
The species name camelopardalis (camelopard) is derived from its early Roman name, where it was described as having characteristics of both a camel and a leopard (and perhaps being a hybrid of the two).
There are nine generally accepted subspecies, differentiated by color and pattern variations and range. One of them the South African Giraffe — rounded or blotched spots, some with star-like extensions on a light tan background, running down to the hooves.
Giraffes are well known for long necks that allow them to browse on the leaves of trees. The bony structure of the neck is essentially unchanged from that of other horse. The giraffe has seven greatly enlarged neck vertebrae (the same number as horses and humans). A giraffe's heart, which can weigh up to 10 kg, has to generate around double the normal blood pressure for a large mammal in order to maintain blood flow to the brain against gravity. In the upper neck, a complex pressure-regulation system called the rete mirabile prevents excess blood flow to the brain when the Giraffe lowers its head to drink. Conversely, the blood vessels in the lower legs are under great pressure (because of the weight of fluid pressing down on them). In other animals such pressure would force the blood out through the capillary walls: Giraffes, however, have a very tight sheath of thick skin over their lower limbs which maintains high extravascular pressure in exactly the same way as a pilot's g-suit.
The pace of the Giraffe is an amble, though when pursued it can run extremely fast. Its leg length compels an unusual gait with the left legs moving together followed by right (similar to pacing) at low speed, and the back legs crossing outside the front at high speed. The small size of its lungs prevents it from supporting a lengthened chase.
The Giraffe defends itself against threats by kicking with great force. A single well-placed kick of an adult giraffe can shatter a lion's skull or break its spine.
The Giraffe has one of the shortest sleep requirement of any mammal, which is reckoned to be between 20 minutes and two hours in a 24 hour period.
A Giraffe will clean off any bugs that appear on its face (usually while eating) with its extremely long tongue (about 18 inches). The tongue is unusually tough on account of the giraffe's diet, which often consists of thorns from the tree it is making a meal of.
Giraffes are thought to be mute. However, recent research has shown evidence that the animal communicates at an infrasound level with a surprising level of complexity.
Plains and woodlands.
Reproduction and social life:
Giraffe gestation lasts between 14 and 15 months after which a single calf is born. The mother gives birth standing up. Newborn giraffes are about 1.8 metres tall. Within a few hours of being born, calves can run around and are indistinguishable from a calf that may be a week old already.
Last edited by gwendolen on Sun Oct 01, 2006 9:27 am, edited 1 time in total.