Giraffe (Giraffa camelopardalis)

Genus: Giraffa
Species: G. camelopardalis
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla
Family: Giraffidae

The giraffe (Giraffa camelopardalis) is an African even-toed ungulate mammal, the tallest of all land-living animal species. Males can be 4.8 to 5.5 meters (16 to 18 feet) tall and weigh up to 900 kilograms (2000 pounds). Females are generally slightly shorter and weigh less.

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).

The instinct of some other African animals is to stay close to the giraffe, for the giraffe's high vantage point can see predators from far away.

Characteristics

Giraffes have spots covering their entire bodies, except their underbellies, with each giraffe having a unique pattern of spots. They have long, prehensile tongues that are distinctly blue. Giraffes have long necks, which they use to browse the leaves of trees. They also have slightly elongated forelegs, about 10% longer than their hind legs. Like nearly all mammals, a giraffe has seven neck vertebrae, which are extremely elongated. These bones produce bud-like horns called ossicorns.

Modifications to the giraffe's structure have evolved, particularly to the circulatory system. A giraffe's heart, which can weigh up to 10 kg (24 lb), 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 maintain high extra vascular pressure in exactly the same way as a pilot's g-suit.

Male giraffes determine female fertility by tasting the female's urine to detect estrus in a multi-step process known as the flehmen response.

Giraffe gestation lasts between 14 and 15 months, after which a single calf is born. The mother gives birth standing up and the embryonic sack actually bursts when the baby falls to the ground. Newborn giraffes are about 1.8 meters tall. Within a few hours of being born, calves can run around and are indistinguishable from a week-old calf; however, for the first two weeks, they spend most of their time lying down, guarded by the mother. While adult giraffes are too large to be attacked by most predators, the young can fall prey to lions, leopards, hyenas, and African Wild Dogs. It has been speculated that their characteristic spotted pattern provides a certain degree of camouflage. Only 25 to 50% of giraffe calves reach adulthood; the life expectancy is between 20 and 25 years in the wild and 28 years in captivity (Encyclopedia of Animals).

The giraffe browses on the twigs of trees, preferring plants of the Mimosa genus; but it appears that it can live without inconvenience on other vegetable food. A giraffe can eat 63 kg (140 lb) of leaves and twigs daily.

The pace of the giraffe is an amble, though when pursued it can run extremely fast. It can not sustain a lengthened chase. 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 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 requirements of any mammal, which is between 20 minutes and two hours in a 24-hour period.

A giraffe will clean off any bugs that appear on its face with its extremely long tongue (about 18 inches). The tongue is tough on account of the giraffe's diet, which includes thorns from the tree it is making a meal of. In Southern Africa, giraffes are partial to all acacias — especially Acacia erioloba — and possess a specially-adapted tongue and lips that appear to be immune to the vicious thorns.

Giraffes are thought to be mute. However, recent research has shown evidence that the animal communicates at an infrasound level.

The English word camelopard first appeared in the 14th century, and survived in common usage well into the 19th century. A number of European languages retain it. The Arabic word ÇáÒÑÇÝÉ ziraafa or zurapha, meaning "assemblage" (of animals), possibly of African origin, was used in English from the sixteenth century on, often in the Italianate form giraffa.