GIRAFFE
The Giraffe (Giraffa camelopardalis meaning ‘fast
walking camel leopard) is an African even-toed ungulate mammal, the tallest of
all land-living animal species.
The
giraffe is related to deer and cattle, however, it is placed in a separate
family, the Giraffidae, consisting only of the giraffe and its closest
relative, the okapi.
The
giraffes range extends from Chad to South Africa. Although the Okapi is much
shorter than the giraffe, it also has a long neck and eats leaves and both
animals have long tongues and skin-covered horns. The giraffes ancestors first
appeared in central Asia about 15 million years ago, however, the earliest
fossil records of the giraffe itself, from Israel and Africa, date back about
1.5 million years.
Males
giraffe are called bulls; female giraffe are called cows; baby giraffe are
called claves.
The
giraffe is the tallest living animal which is instantly recognizable by its
exceptionally long neck. Adult males stand 15 – 19 feet (4.6 – 6.0 metres)
tall, whereas females are shorter at 13 – 16 feet (4 – 4.8 metres) tall. Adult
males weigh between 1,764 – 4,255 pounds (800 – 930 kilograms), while females
weigh only 1,213 – 2,601 pounds (550 – 1,180 kilograms). The giraffe has the
longest tail of any land mammal. Their tail can grow to be 8 feet (2.4 metres)
long, including the tuft on the end.
In
addition to its great height, the giraffe is also one of the heaviest land
animals. Exceptionally large males may weigh up to 1,900 kilograms (about 4,200
pounds). Female giraffes are smaller, rarely reaching half that weight.
Compared to other hoofed mammals the giraffe has a relatively short body,
however, its legs are disproportionately long.
A
giraffes front legs are about 10% longer than their hind legs, a feature that
contributes to the animals steeply sloping back. Mature giraffes have large
hooves about the size of dinner plates, around 12 inches wide.
Giraffes
can inhabit savannas, grasslands or open woodlands. Giraffes prefer areas
enriched with acacia growth (a genus of shrubs and trees). Most giraffes live
either in East Africa or in Angola and Zambia in southwestern Africa. Until the
middle of the 20th century giraffes were also commonly found in West Africa,
south of the Sahara. But populations there have fallen sharply and become
increasingly fragmented.
Giraffes
live in habitats where the available food varies throughout the year. During
the dry season, giraffes eat evergreen leaves, however, once the rainy season
begins, they switch to new leaves and stems that sprout on deciduous trees.
Also, twigs and branches are pulled into the mouth of the giraffe with their
long and dextrous tongues. In the wild giraffes can eat up to 66 kilograms of
food daily.
When
there is a choice, male and female giraffes feed in different ways. Males
concentrate on leaves from the highest branches, while the females arch their
necks to eat closer to the ground. Because of this characteristic behaviour, a
giraffe can be identified as either male or female from a long distance away
simply by its stance while eating. Male giraffes are also more inclined to
wander into dense woodland, a habitat that females generally avoid.
Giraffes
drink large quantities of water and as a result, they can spend long periods of
time in dry, arid areas. When searching for more food they will venture into
areas with denser foliage. The giraffe has tough lips to ensure there is no
damage to their mouths when chewing at trees and twigs such as thorns.
Giraffes
in captivity are generally fed on alfalfa hay and pellets, apples, carrots,
bananas and browse (elm and alder are favourites).
Female
giraffes associate in groups of a dozen or so members, occasionally including a
few younger males. Male giraffes tend to live in bachelor herds, with older
males often leading solitary lives. A individual giraffe can join or leave the
herd at any time and for no particular reason.
Because
giraffes are so widely scattered, it may seem that they do not keep in contact
with each other, however, this is not true. A giraffes keen eyesight means they
can keep an eye on their neighbours even at a distance.
Female
giraffes spend just over half a 24 hour day browsing, male giraffes spend less
time doing this – about 43% of the time that the female does. Night is mostly
spent lying down ruminating, especially in the hours after dark and before
dawn. Male giraffes spend about 22% of the 24 hours walking, compared to 13%
for female giraffes. The rest of the time male giraffes are searching for a
female giraffe to mate with. Giraffe herds do not have a leader and individual
giraffes show no particular preferences for others in the herd. Young giraffes
are never left alone, however, they are looked after in a kind of nursery group
where the females help look after each others calves (baby giraffes).
Giraffes
spend up to half their time feeding and most of the remainder is taken up
either by searching for food or slowly digesting what they have eaten.
Sometimes giraffes sleep during the daytime, often while standing. Giraffes
normally lie down only at night, tucking their feet under the body and usually
keeping the head upright. However, when a giraffe is sleeping, something it
does only for just a few minutes at a time, it curves its neck around and rests
its head on or near its behind.
One
of the most fascinating elements of giraffe behaviour is the duel between males
fighting for mating partners. Giraffe duels are among the most extraordinary in
the animal kingdom. Duels begin when two males approach each other and engage
in rubbing and intertwining their necks. This behaviour is known as ‘necking’.
It allows the opponents to assess each others size and strength.
Often,
necking alone is enough to establish dominance. If not, the rivals begin to
exchange blows with their heads, using their short horns to tackle each other.
Each
giraffe braces its front legs and swings its head upward and over its shoulder.
If a blow lands solidly, the giraffe may stagger under the impact and in rare
cases may even collapse onto the ground. More often the contest breaks off
after a few minutes and the loser simply walks away.
The
Giraffe breeding season can occur at any time during the year. However, births
in the wild usually happen during the dry season and births in captivity can
happen all year round., however, in the wild, males do not usually breed until
they are 6 – 7 years old. In contrast to the male breeding age, females must be
physically larger to carry offspring.
When
male giraffes are ready to breed, they begin the ritual combat over mates.
Giraffes are non- territorial and a successful male giraffe will mate with
receptive female giraffes whenever and wherever it finds them. Gestation period
is usually 13 – 15 months and when a pregnant female giraffe is ready to give
birth, she makes her way to a calving area that she will use throughout her
life. The moment of birth is dramatic, with the mother giraffe standing on all
fours and the calf tumbling onto the ground. Remarkably, the calf is rarely
injured by its fall.
Newborn
giraffes are often on their feet within 20 minutes and are soon feeding on
their mothers milk. Calves can walk about an hour after birth and can run
within 24 hours of birth. Giraffe calves are about 2 metres (6 feet) tall at
birth and weigh 104 – 154 pounds. Giraffe calves grow about 3 centimetres tall
each day during the first week and double their height in their first year.
By
the age of one year giraffe calves can measure 10 feet tall. Giraffe calves are
weaned at one year and become fully independent by 15 months of age. Female
giraffe calves are fully grown by age five and male giraffe calves by the age
of seven.
Young
giraffes may suckle for up to a year, however, they start to sample plants just
a few weeks after birth. Giraffe calves are ready to leave the protection of
their mother after 15 – 18 months of development.
Adult
giraffes generally have no predators other than lions and humans, as their huge
hooves are very effective in defending against predators. Giraffes are more
vulnerable when they are lying down or drinking, because this gives lions the
opportunity to leap up and seize them by the nose or throat. Newly born calves
are at much greater risk. Despite their mothers best efforts to protect them,
over 50 percent of all giraffe newborns are killed by hyenas and big cats
such as lions and
leopards during the first month of their life.In captivity, giraffes have lived
over the age of 30 years, however, their maximum life span in the wild is about
25 years.
Giraffes
have two ways of moving, a loping walk and a gallop. When they walk, the
giraffes move both feet on one side of their body in unison, followed by both
feet on the other side. When they run, giraffes move the front feet together,
then the back feet, swinging the hind feet up and planting them in front of the
forefeet. While running, the neck of a giraffe moves backward and forward to
keep the animal balanced. Giraffes have a top speed of about 56 kilometres per
hour (35 miles per hour), however, because its legs are so long a galloping
giraffe does not appear to be going very fast.
Giraffes
are not great travelers, despite their long legs. Giraffes cannot walk over
swampy ground because their hooves quickly sink and they very rarely wade
across rivers. Giraffes on opposite banks of a river may never come into
contact, unless the water levels drop.
For
giraffes, bending down is a daily challenge. To reach ground level for example,
when drinking a giraffe has to splay its front legs at an angle of almost 45
degrees. A giraffes circulatory system is also specially modified, because the
high pressure needed to pump blood up to its head could cause brain damage when
the head is lowered. To deal with this problem, giraffes have elastic blood
vessels that relieve some of the excess pressure.
Giraffes
also have a series of valves in their neck veins that ensure that blood always
flows from the head back towards the heart, even when this means going against
gravity. When giraffes do bend down to drink at water holes, it is commonly
done in pairs. This is so that one giraffe can drink, whilst the other keeps an
eye open for predators.
Giraffes
are usually silent although they can bellow, grunt or snort when alarmed, as
when confronted by lions, and can also moo in distress.
Hold
your mouse over the giraffe photo and you may be able to hear a giraffe grunt.
(ie only)
Calves
(young giraffes) bleat and make a mewing call, cows (female giraffes) seeking
lost calves will bellow and courting bulls (male giraffes) may emit a raucous
cough. Giraffes also give alarm snorts, whereby moaning, snoring, hissing and
flute like sounds have been reported. Giraffes also give out a grunting sound
that sounds like a pig.
Giraffes
have amazing adaptions that help them with their lifestyle in the wild. Because
giraffes grow to a very tall height, it gives them access to a level of foliage
beyond reach of all other large browsing animals all except possibly, the
elephant. Along with their height, giraffes have an incredible array of
adaptations. For example, their skin colouring provides excellent camouflage,
as it has many different patches of variable size and colour.
Giraffes
skin is very thick, so it provides ample protection and insulation. Also, the
giraffe’s long eyelids keep out ants and sense thorns on the branches of the
trees from which they browse. The valves in veins of the neck control a huge
rush of blood to the head when leaning over; this prevents unconsciousness.
There is also a network of capillaries in the brain called the ‘wonder-net’. It
acts rather like a shock absorber and is another part of the system that
prevents unconsciousness. (Also see ‘Anatomy‘
for more facts about the giraffes neck).
A
giraffes tongue is over 18 inches (46 centimetres) long, and the roof of the
mouth is grooved to easily strip leaves off branches. Since giraffes are
extremely efficient at processing nutrients and liquids from food, they can
survive without water for long periods of time. Giraffes ruminate day or night,
with periods of sleep in between.
Giraffes
also rest with their eyes open, standing or lying for three to five minutes at
a time. Throughout the night, a giraffe may deeply sleep for five to 10 minutes
lying down, yet they rarely sleep more than 20 minutes total per day.
Like
many of Africas large mammals, giraffes have declined in numbers and in range
over the last century. At one time, herds of over 100 animals were common in savanna
regions across the continent, however, today concentrations like these exist
only in East Africa particularly Tanzania Serengeti National Park.
The
decline of giraffe populations has largely been due to hunting. In Africa, the
giraffe is a traditional source of hide and hair and also of tough but
nutritious meat. Hunting of giraffes has not yet had a catastrophic effect, as
it has on some of Africas big-game animals, but it is a cause for concern. The
natural habitat of the giraffe is also being impacted more and more by human
activities, reducing the animals range.
The
giraffe is currently a protected species throughout most of its range and is classed
as conservation-dependent by the World Conservation Union (IUCN). The giraffes
prospects for survival are good for those living in national parks and game
reserves, but for animals living outside these areas the future is less secure.
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