The Giraffe

Mozambique Company - Scott #175 (1937)
Mozambique Company – Scott #175 (1937)

Riding the local version of a bus (called a songtesaw, meaning “three seats”) to work today, I decided I wanted to write a “random stamp day” article about giraffes. I felt it would be an “easy” topic compared with the recent marathons involved putting together the articles on Jamestown (more than 11,000 words) and Air Mail/Inverted Jenny (almost 6200 words). I need to do a few short articles over the next few days so I’m well-rested for Sunday’s Lindbergh anniversary (my current plan is for a background-to-takeoff article on the 20th and a Paris-to-aftermath article on the 21st). Either way, Lindbergh will be another lengthy undertaking. It turns out that I have already featured a giraffe on a previous ASAD article, the issuer profile on Ethiopia; however, my description of the tallest living terrestrial animal back in late November 2016 was only an introduction. Here is the rest of the story…

The name “giraffe” has its earliest known origins in the Arabic word zarāfah (زرافة), perhaps borrowed from the animal’s Somali name geri. The Arab name is translated as “fast-walker”. There were several Middle English spellings, such as jarraf, ziraph, and gerfauntz. The Italian form giraffa arose in the 1590s. The modern English form developed around 1600 from the French giraffe. “Camelopard” is an archaic English name for the giraffe deriving from the Ancient Greek for camel and leopard, referring to its camel-like shape and its leopard-like coloring.

Living giraffes were originally classified as one species by Carl Linnaeus in 1758. He gave it the binomial name Cervus camelopardalis. Morten Thrane Brünnich classified the genus Giraffa in 1772. The species name camelopardalis is from Latin. Taxonomic classifications of one to eight extant giraffe species have been described, based upon research into the mitochondrial and nuclear DNA, as well as morphological measurements of Giraffa, but the International Union for Conservation of Nature (IUCN) currently recognizes only one species with nine subspecies.  Seven other species are extinct, prehistoric species known from fossils.

Geographic distribution of the giraffe (Giraffa camelopardalis).
Geographic distribution of the giraffe (Giraffa camelopardalis).

The giraffe is one of only two living genera of the family Giraffidae in the order Artiodactyla, the other being the okapi. The family was once much more extensive, with over 10 fossil genera described. Their closest known relatives are the extinct deer-like climacocerids. They, together with the family Antilocapridae (whose only extant species is the pronghorn), belong to the superfamily Giraffoidea. These animals may have evolved from the extinct family Palaeomerycidae which might also have been the ancestor of deer.

The elongation of the neck appears to have started early in the giraffe lineage. Comparisons between giraffes and their ancient relatives suggest that vertebrae close to the skull lengthened earlier, followed by lengthening of vertebrae further down. One early giraffid ancestor was Canthumeryx which has been dated variously to have lived 25–20 million years ago, 17–15 million years ago or 18–14.3 million years ago and whose deposits have been found in Libya. This animal was medium-sized, slender and antelope-like. Giraffokeryx appeared 15 million years ago in the Indian subcontinent and resembled an okapi or a small giraffe, and had a longer neck and similar ossicones. Giraffokeryx may have shared a clade with more massively built giraffids like Sivatherium and Bramatherium.

Bohlinia, which first appeared in southeastern Europe and lived 9–7 million years ago was likely a direct ancestor of the giraffe. Bohlinia closely resembled modern giraffes, having a long neck and legs and similar ossicones and dentition. Bohlinia entered China and northern India in response to climate change. From there, the genus Giraffa evolved and, around 7 million years ago, entered Africa. Further climate changes caused the extinction of the Asian giraffes, while the African giraffes survived and radiated into several new species. Living giraffes appear to have arisen around 1 million years ago in eastern Africa during the Pleistocene.

The extinct giraffid Samotherium (middle) in comparison with the okapi (below) and giraffe. The anatomy of Samotherium appears to have shown a transition to a giraffe-like neck.
The extinct giraffid Samotherium (middle) in comparison with the okapi (below) and giraffe. The anatomy of Samotherium appears to have shown a transition to a giraffe-like neck.

In the early 19th century, Jean-Baptiste Lamarck believed the giraffe’s long neck was an “acquired characteristic”, developed as generations of ancestral giraffes strove to reach the leaves of tall trees. This theory was eventually rejected, and scientists now believe the giraffe’s neck arose through Darwinian natural selection—that ancestral giraffes with long necks thereby had a competitive feeding advantage (competing browsers hypothesis) that better enabled them to survive and reproduce to pass on their genes.

The giraffe genome is around 2.9 billion base pairs in length compared to the 3.3 billion base pairs of the okapi. Of the proteins in giraffe and okapi genes, 19.4% are identical. The two species are equally distantly related to cattle, suggesting the giraffe’s unique characteristics are not because of faster evolution. The divergence of giraffe and okapi lineages dates to around 11.5 million years ago. A small group of regulatory genes in the giraffe appear to be responsible for the animal’s stature and associated circulatory adaptations.

The IUCN currently recognizes only one species of giraffe with nine subspecies. In 2001, a two-species taxonomy was proposed. A 2007 study on the genetics of Giraffa, suggested they were six species: the West African, Rothschild’s, reticulated, Masai, Angolan, and South African giraffe. The study deduced from genetic differences in nuclear and mitochondrial DNA (mtDNA) that giraffes from these populations are reproductively isolated and rarely interbreed, though no natural obstacles block their mutual access. This includes adjacent populations of Rothschild’s, reticulated, and Masai giraffes. The Masai giraffe was also suggested to consist of possibly two species separated by the Rift Valley.

Reticulated and Masai giraffes have the highest mtDNA diversity, which is consistent with giraffes originating in eastern Africa. Populations further north are more closely related to the former, while those to the south are more related to the latter. Giraffes appear to select mates of the same coat type, which are imprinted on them as calves. The implications of these findings for the conservation of giraffes were summarized by David Brown, lead author of the study, who told BBC News: “Lumping all giraffes into one species obscures the reality that some kinds of giraffe are on the brink. Some of these populations number only a few hundred individuals and need immediate protection.”

“Approximate geographic ranges, fur patterns, and phylogenetic relationships between some giraffe subspecies based on mitochondrial DNA sequences. Colored dots on the map represent sampling localities. The phylogenetic tree is a maximum-likelihood phylogram based on samples from 266 giraffes. Asterisks along branches correspond to node values of more than 90% bootstrap support. Stars at branch tips identify paraphyletic haplotypes found in Maasai and reticulated giraffes”.

A 2011 study using detailed analyses of the morphology of giraffes, and application of the phylogenetic species concept, described eight species of living giraffes. The eight species are: G. angolensis, G.antiquorum, G. camelopardalis, G. giraffa, G. peralta, G. reticulata, G. thornicrofti, and G. tippelskirchi.

A 2016 study also concluded that living giraffes consist of multiple species. The researchers suggested the existence of four species, which have not exchanged genetic information between each other for 1 million to 2 million years. Those four species are the northern giraffe (G. camelopardalis), southern giraffe (G. giraffa), reticulated giraffe (G. reticulata), and Masai giraffe (G. tippelskirchi). Since then, a response to this publication has been published, highlighting seven problems in data interpretation, and concludes “the conclusions should not be accepted unconditionally”.

There are an estimated 90,000 individuals of Giraffa in the wild, with 1,144 currently in captivity.

An adult female Masai giraffe in the Masaai Mara National Park, Kenya. Photo taken on August 22, 2012.
An adult female Masai giraffe in the Masaai Mara National Park, Kenya. Photo taken on August 22, 2012.

Fully grown giraffes stand 14.1 tp 18.7 feet (4.3–5.7 m) tall, with males taller than females. The tallest recorded male was 19.3 feet  (5.88 m) and the tallest recorded female was 17 feet  (5.17 m) tall. The average weight is 2,628 pounds (1,192 kg) for an adult male and 1,825 pounds (828 kg) for an adult female] with maximum weights of 4,250 pounds (1,930 kg) and 2,600 pounds (1,180 kg) having been recorded for males and females, respectively. Despite its long neck and legs, the giraffe’s body is relatively short. Located at both sides of the head, the giraffe’s large, bulging eyes give it good all-round vision from its great height. Giraffes see in color and their senses of hearing and smell are also sharp. The animal can close its muscular nostrils to protect against sandstorms and ants.

The giraffe’s prehensile tongue is about 18 inches (45 cm) long. It is purplish-black in color, perhaps to protect against sunburn, and is useful for grasping foliage, as well as for grooming and cleaning the animal’s nose. The upper lip of the giraffe is also prehensile and useful when foraging and is covered in hair to protect against thorns. The tongue, and inside of the mouth are covered in papillae.

The coat has dark blotches or patches (which can be orange, chestnut, brown, or nearly black in color) separated by light hair (usually white or cream in color). Male giraffes become darker as they age. The coat pattern has been claimed to serve as camouflage in the light and shade patterns of savannah woodlands. While adult giraffes standing among trees and bushes are hard to see at even a few feet distance, they actively move into the open to gain the best view of an approaching predator, obviating any benefit that camouflage might bring. Instead, the adults rely on their size and ability to defend themselves. However, camouflage appears to be important for calves, which spend a large part of the day in hiding, away from their mothers; further, over half of all calves die within a year, so predation is certainly important. It appears, therefore, that the spotted coat of the giraffe functions as camouflage for the young, while adults simply inherit this coloration as a by-product. The skin underneath the dark areas may serve as windows for thermoregulation, being sites for complex blood vessel systems and large sweat glands. Each individual giraffe has a unique coat pattern.

Closeup of the head of a giraffe (Giraffa camelopardalis), at the Melbourne Zoo, Australia.
Closeup of the head of a giraffe (Giraffa camelopardalis), at the Melbourne Zoo, Australia.

The skin of a giraffe is mostly gray. Its thickness allows the animal to run through thorn bush without being punctured. The fur may serve as a chemical defense, as its parasite repellents give the animal a characteristic scent. At least 11 main aromatic chemicals are in the fur, although indole and 3-methylindole are responsible for most of the smell. Because the males have a stronger odor than the females, the odor may also have sexual function. Along the animal’s neck is a mane made of short, erect hairs. The 3.3-foot (one meter) tail ends in a long, dark tuft of hair and is used as a defense against insects.

Both sexes have prominent horn-like structures called ossicones, which are formed from ossified cartilage, covered in skin and fused to the skull at the parietal bones. Being vascularized, the ossicones may have a role in thermoregulation, and are also used in combat between males. Appearance is a reliable guide to the sex or age of a giraffe: the ossicones of females and young are thin and display tufts of hair on top, whereas those of adult males end in knobs and tend to be bald on top. Also, a median lump, which is more prominent in males, emerges at the front of the skull. Males develop calcium deposits that form bumps on their skulls as they age. A giraffe’s skull is lightened by multiple sinuses. However, as males age, their skulls become heavier and more club-like, helping them become more dominant in combat. The upper jaw has a grooved palate and lacks front teeth. The giraffe’s molars have a rough surface.

The front and back legs of a giraffe are about the same length. The radius and ulna of the front legs are articulated by the carpus, which, while structurally equivalent to the human wrist, functions as a knee. It appears that a suspensory ligament allows the lanky legs to support the animal’s great weight. The foot of the giraffe reaches a diameter of 12 inches (30 cm), and the hoof is 5.9 inches (15 cm) high in males and 3.9 inches (10 cm) in females. The rear of each hoof is low and the fetlock is close to the ground, allowing the foot to provide additional support to the animal’s weight. Giraffes lack dewclaws and interdigital glands. The giraffe’s pelvis, though relatively short, has an ilium that is outspread at the upper ends.

Reticulated giraffe bending down to drink, at dusk at Ol Pejeta Ranch in Kenya. The circulatory system is adapted to deal with blood flow rushing down its neck. Photo taken on July 10, 2010.
Reticulated giraffe bending down to drink, at dusk at Ol Pejeta Ranch in Kenya. The circulatory system is adapted to deal with blood flow rushing down its neck. Photo taken on July 10, 2010.

A giraffe has only two gaits: walking and galloping. Walking is done by moving the legs on one side of the body at the same time, then doing the same on the other side. When galloping, the hind legs move around the front legs before the latter move forward, and the tail will curl up. The animal relies on the forward and backward motions of its head and neck to maintain balance and the counter momentum while galloping. The giraffe can reach a sprint speed of up to 37 miles per hour (60 km/h), and can sustain 31 miles per hour (50 km/h) for several miles.

A giraffe rests by lying with its body on top of its folded legs. To lie down, the animal kneels on its front legs and then lowers the rest of its body. To get back up, it first gets on its knees and spreads its hind legs to raise its hindquarters. It then straightens its front legs. With each step, the animal swings its head. In captivity, the giraffe sleeps intermittently around 4.6 hours per day, mostly at night. It usually sleeps lying down, however, standing sleeps have been recorded, particularly in older individuals. Intermittent short “deep sleep” phases while lying are characterized by the giraffe bending its neck backwards and resting its head on the hip or thigh, a position believed to indicate paradoxical sleep. If the giraffe wants to bend down to drink, it either spreads its front legs or bends its knees. Giraffes would probably not be competent swimmers as their long legs would be highly cumbersome in the water, although they could possibly float. When swimming, the thorax would be weighed down by the front legs, making it difficult for the animal to move its neck and legs in harmony or keep its head above the surface.

The giraffe has an extremely elongated neck, which can be up to 6.6 to 7.9 feet (2–2.4 mt) in length, accounting for much of the animal’s vertical height. The long neck results from a disproportionate lengthening of the cervical vertebrae, not from the addition of more vertebrae. Each cervical vertebra is over 11 inches (28 cm) long. They comprise 52–54 per cent of the length of the giraffe’s vertebral column, compared with the 27–33 percent typical of similar large ungulates, including the giraffe’s closest living relative, the okapi. This elongation largely takes place after birth, perhaps because giraffe mothers would have a difficult time giving birth to young with the same neck proportions as adults. The giraffe’s head and neck are held up by large muscles and a strengthened nuchal ligament, which are anchored by long dorsal spines on the anterior thoracic vertebrae, giving the animal a hump.

Adult male reticulated giraffe feeding high up on an acacia, in Samburu Park, Kenya. Photo taken on July 8, 2010.
Adult male reticulated giraffe feeding high up on an acacia, in Samburu Park, Kenya. Photo taken on July 8, 2010.

The circulatory system of the giraffe has several adaptations for its great height. Its heart, which can weigh more than 25 pounds (11 kg) and measures about 2 feet (60 cm) long, must generate approximately double the blood pressure required for a human to maintain blood flow to the brain. As such, the wall of the heart can be as thick as 3 inches (7.5 cm). Giraffes have unusually high heart rates for their size, at 150 beats per minute. When the animal lowers its head the blood rushes down fairly unopposed and a rete mirabile in the upper neck, with its large cross sectional area, prevents excess blood flow to the brain. When it raises again, the blood vessels constrict and direct blood into the brain so the animal does not faint. The jugular veins contain several (most commonly seven) valves to prevent blood flowing back into the head from the inferior vena cava and right atrium while the head is lowered. Conversely, the blood vessels in the lower legs are under great pressure because of the weight of fluid pressing down on them. To solve this problem, the skin of the lower legs is thick and tight; preventing too much blood from pouring into them.

Giraffes have oesophageal muscles that are unusually strong to allow regurgitation of food from the stomach up the neck and into the mouth for rumination. They have four chambered stomachs, as in all ruminants, and the first chamber has adapted to their specialized diet. The intestines of an adult giraffe measure more than 230 feet (70 m) in length and have a relatively small ratio of small to large intestine. The liver of the giraffe is small and compact. A gallbladder is generally present during fetal life, but it may disappear before birth.

Humans have interacted with giraffes for millennia. The San people of southern Africa have medicine dances named after some animals; the giraffe dance is performed to treat head ailments. How the giraffe got its height has been the subject of various African folktales, including one from eastern Africa which explains that the giraffe grew tall from eating too many magic herbs. Giraffes were depicted in art throughout the African continent, including that of the Kiffians, Egyptians and Meroë Nubians. The Kiffians were responsible for a life-size rock engraving of two giraffes that has been called the “world’s largest rock art petroglyph”. The Egyptians gave the giraffe its own hieroglyph, named ‘sr‘ in Old Egyptian and ‘mmy‘ in later periods. They also kept giraffes as pets and shipped them around the Mediterranean.

Painting of a giraffe imported to China during the Ming dynasty. Ink and color on silk; mounted as a hanging scroll - 1414, 9th month of the 12th year of the Yongle reign, Ming dynasty. Currently in the collections of the Philadelphia Museum of Art
Painting of a giraffe imported to China during the Ming dynasty. Ink and color on silk; mounted as a hanging scroll – 1414, 9th month of the 12th year of the Yongle reign, Ming dynasty. Currently in the collections of the Philadelphia Museum of Art

The giraffe was also known to the Greeks and Romans, who believed that it was an unnatural hybrid of a camel and a leopard and called it camelopardalis. The giraffe was among the many animals collected and displayed by the Romans. The first one in Rome was brought in by Julius Caesar in 46 BC and exhibited to the public. With the fall of the Western Roman Empire, the housing of giraffes in Europe declined. During the Middle Ages, giraffes were known to Europeans through contact with the Arabs, who revered the giraffe for its peculiar appearance.

Individual captive giraffes were given celebrity status throughout history. In 1414, a giraffe was shipped from Malindi to Bengal. It was then taken to China by explorer Zheng He and placed in a Ming dynasty zoo. The animal was a source of fascination for the Chinese people, who associated it with the mythical Qilin. The Medici giraffe was a giraffe presented to Lorenzo de’ Medici in 1486. It caused a great stir on its arrival in Florence. Zarafa, another famous giraffe, was brought from Egypt to Paris in the early 19th century as a gift from Muhammad Ali of Egypt to Charles X of France. A sensation, the giraffe was the subject of numerous memorabilia or “giraffanalia”.

Giraffes continue to have a presence in modern culture. Salvador Dalí depicted them with burning manes in some of his surrealist paintings. Dali considered the giraffe to be a symbol of masculinity, and a flaming giraffe was meant to be a “masculine cosmic apocalyptic monster”. Several children’s books feature the giraffe, including David A. Ufer’s The Giraffe Who Was Afraid of Heights, Giles Andreae’s Giraffes Can’t Dance and Roald Dahl’s The Giraffe and the Pelly and Me. Giraffes have appeared in animated films, as minor characters in Disney’s The Lion King and Dumbo, and in more prominent roles in The Wild and in the Madagascar films. Sophie the Giraffe has been a popular teether since 1961. Another famous fictional giraffe is the Toys “R” Us mascot Geoffrey the Giraffe.

Fighting giraffes in Ithala Game Reserve, northern KwaZulu-Natal, South Africa. Photo taken on July 6, 2004.
Fighting giraffes in Ithala Game Reserve, northern KwaZulu-Natal, South Africa. Photo taken on July 6, 2004.

On May 16, 1937, the Mozambique Company (Companhia de Moçambique) issued what would turn out to be its last set of definitive stamps (Scott #173-193). The 17 beautiful pictorial stamps depicted a wide range of locally relevant subjects. This royal company operating in Portuguese Mozambique (also known as Portuguese East Africa — África Oriental Portuguesa) administered the provinces of Manica and Sofala in the present-day Republic of Mozambique. This amounted to 51,881 square miles of territory. Part of the charter of the Mozambique Company was the right to issue stamps, which it did from 1892 until 1942.

Scott #175 was the lowest denomination of the 1937 pictorial set. The 1-centavo yellow green and violet stamp was issued with a perforation gauge of 12½, the only stamp of this particular entity to portray a giraffe. It is the third stamp ASAD has featured from the Mozambique Company — the first accompanied the issuer profile — and the second from this particular set (the zebra stamp, Scott #179).

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