A giraffe is a large, hoofed mammal belonging to the genus Giraffa. This genus includes a single living species, Giraffa camelopardalis. Traditionally, the term ‘giraffe’ refers to this species, which is divided into nine subspecies. As of 2018, the IUCN also recognizes giraffes as a single species. However, many researchers suggest that giraffes should be classified as four distinct species, though a consensus has yet to be reached.
Scientific Classification
Animalia
Chordata
Mammalia
Artiodactyla
Giraffidae
Giraffa
Scientific Classification
Animalia
Chordata
Mammalia
Artiodactyla
Giraffidae
Giraffa
Giraffes are native to sub-Saharan Africa, where they typically occupy savannahs and woodlands. They are characterized by extremely long necks and a body coat marked with distinctive dark blotches. In fact, they are the tallest of all terrestrial animals and the largest ruminant on this planet.
Primarily browsers, giraffes typically feed on leaves, especially from the higher branches of acacia trees. To be able to reach these branches, they are also equipped with a long, prehensile tongue, about 18 in (45 cm) long.Although the giraffe is fairly common in many national parks and game reserves, it is locally extinct in many parts of its former range. The IUCN Red List of Threatened Species lists this animal under the Vulnerable (VU) category.
Types of Giraffes
Subspecies
Traditionally, the giraffe (Giraffa camelopardalis) has 9 subspecies.
Body and Coloration: These mammals have a notably long neck, measuring up to 7.9 ft (2.4 m) in length, lined by a mane made of short, erect hair. The elongation of the neck is a result of the lengthening of the cervical vertebrae and not from the addition of more vertebrae. It is believed that this elongation helps these animals reach the highest tree branches, which their herbivorous competitors occupying the same habitat cannot.
Giraffe
Their heads bear a pair of prominent horn-like structures called ossicones, which may measure over 5 in (12.7 cm). These structures are highly vascularized, composed of ossified cartilage, and are covered in skin. During fights, the males attempt to strike each other using these ossicones, and these structures also likely play a role in thermoregulation.
The head and neck of giraffes are supported by large muscles and a nuchal ligament, which, in turn, are anchored by spines on the thoracic vertebrae. These spines appear as a raised hump when viewed from the side.
With age, male giraffes gradually develop a large lump in the middle of their skull, which is nothing but a deposition of calcium that functions as a weapon during combats.
Their front legs are longer than the hind legs, an adaptation that helps support the long and heavy neck and head. In males, the front legs are particularly long, helping them maintain balance while swinging their necks during combat. The hooves of large males measure 12.2 in × 9.1 in (31 cm × 23 cm) in diameter.
The body coat bears dark blotches or patches, ranging from orange to near-black in color, depending on the subspecies. These patches help the animals camouflage themselves in the dappled light of savannahs and woodlands. Each giraffe features a unique coat pattern.
The skin beneath the blotches bears complex blood vessels and large sweat glands, likely playing a role in thermoregulation.
Distribution
They extend across sub-Saharan Africa, from Chad in the north to South Africa in the south, and Niger in the west to Somalia in the east.
Habitat
Giraffes typically inhabit savannahs and open woodlands, though the Angolan giraffe lives in arid and semi-arid regions.
They prefer living in areas replete with trees belonging to the tribe Acacieae (acacias), as well as those in the genera Commiphora, Combretum, and Terminalia.
Giraffe Habitat
Giraffe Tongue
Diet
They are grazing herbivores that typically feed on leaves, flowers, fruits, and pods from trees and shrubs. Their preferred choice is the leaves of acacias.
During dry periods, when leaves are scarce, giraffes may feed on grass, though they are not experts at grazing. They may also chew on large branches, stripping their bark for roughage and minerals. On average, a giraffe consumes around 75 lb (35 kg) of plant matter daily. Occasionally, they also chew old bones for their mineral content.
In arid regions of Namibia, giraffes have been observed going for weeks or even months without drinking water, relying instead on the moisture obtained from the leaves consumed.
Giraffe Diet
Giraffe Face
Behavior
The giraffe has only two patterns of movement, walking and galloping. While walking, the legs on one side of the body move first, followed by those on the other side. When galloping, the hind legs move past the front legs before the front legs swing forward. The tail curls up, while the head and neck maintain the balance and momentum of the gallop. Typically, giraffes can move at 50 km/h (31 mph) for kilometers, often reaching 60 km/h (37 mph) in short bursts.
These animals typically sleep by lying down, their bodies resting on top of their folded legs. To lie down, they first kneel on their front legs and then lower the rest of their body. In contrast, when they need to get back up, they first get on their front knees and then raise the hind part of their bodies.
As ruminants, giraffes chew the food, swallow it for processing in their multi-chambered stomach, and then regurgitate the cud up the neck to the mouth for further physical breakdown. They typically feed during the first and last hours of the day, standing and ruminating in between.
Giraffes usually form social groups, sometimes comprising as many as 60 individuals. These groups often tend to be sex-segregated (though mixed-sex groups are also common) and may expand to larger groups or dissociate into smaller subgroups.
To assert superiority, male giraffes use their long necks to fight each other, a behavior called necking. During low-intensity necking, the males remain upright, rubbing and leaning on each other. In contrast, during high-intensity necking, they spread their front legs and swing their necks, trying to strike each other with their ossicones. However, surprisingly enough, males often try to caress and court each other after a battle.
Lifespan
They typically live between 10 and 15 years in the wild. However, some individuals have been found to survive over 30 years in captivity.
Reproduction and Life Cycle
Giraffes are polygynous, with only a few older males mating with the young, fertile females. The females are capable of mating year-round since they undergo estrus approximately every 15 days. These receptive females are often scattered in space and time, and thus, the male roams among female groups, seeking the chance to mate.
To assess a female’s sexual receptivity, the male sniffs or tastes her urine and performs a flehmen response by curling back the upper lip. Once the estrus female is detected, the male tries to court her by emitting loud coughs. He may also lick the female’s tail, lay his head on her body, and nudge her with his ossicones. During mating, the male stands on his hind legs and raises the front legs by the sides of the female, holding her tightly.
The female undergoes a gestation period of 400 to 460 days, following which she gives birth to a single calf or, rarely, twins. She typically gives birth while standing, and the calf emerges head and front legs first, falling straight on the ground. The newborn is 5 ft 7 in to 6 ft 7 in (1.7 to 2 m) tall and is capable of running around in about a week. However, it remains hidden for up to three weeks.
The females, along with their calves, often form temporary groups called nursery herds or calving pools. In these groups, several mothers and their calves stay together, browsing and moving together. Sometimes, a mother may leave her calf with a trusted female to forage at distant sites. In such circumstances, the calf may sometimes suckle the non-parental female (allo-sucking).
The calves begin to ruminate when they are about 4 to 6 months old and stop suckling when they are about 8 months old. The female calves attain sexual maturity when they are about 4 years old, while males become mature around 7 years old.
Giraffe Baby
Giraffe Images
Predators and Parasites
Owing to their large size, good eyesight, and powerful kicks, healthy adults have very few natural predators. However, the calves and weaker adults are preyed upon by lions, leopards, spotted hyenas, and wild dogs. Occasionally, when giraffes are around water bodies, they are killed by Nile crocodiles.
Several ticks, particularly those of the genera Hyalomma, Amblyomma, and Rhipicephalus, parasitize the area around the genitals in giraffes.
Adaptations
Giraffes have a large heart, about 11 kg (25 lb) in weight and 60 cm (2 ft) in length. The organ has thick walls and pumps blood with about twice the pressure of a human heart. Such an adaptation helps overcome the challenge of pumping blood up to the brain. These animals also have a fast heart rate for their size, around 150 beats per minute.
As the giraffe lowers its head for activities, such as drinking water, blood could rush down too quickly and harm the brain. To prevent this, they possess a network of blood vessels with a large cross-sectional area in the upper neck (rete mirabile), which prevents excess blood flow to the brain.
They are equipped with specialized esophageal muscles that help them regurgitate the ingested food up the neck to the mouth. Moreover, they also have four-chambered stomachs that help them break down hard-to-digest fibrous plant material.
Their eyes are positioned on the sides of the head, providing a broad visual field to scan the landscape they inhabit. Unlike many other ungulates, giraffes have a greater degree of binocular vision, relatively large eyes, and a greater retinal surface area.
The sebaceous glands in the skin of giraffes produce at least 11 primary aromatic chemicals that release a characteristic odor and help repel insects.
Interesting Facts
They have the longest left recurrent laryngeal nerve among all animals, measuring over 2 m (6 ft 7 in) in length. This nerve originates in the brainstem, descends the length of the neck via the vagus nerve, loops around the aortic arch, and ascends again to innervate the larynx.
