Reticulated giraffe

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Reticulated giraffe
Reticulated giraffe in the Karlsruhe Zoo

Reticulated giraffe in the Karlsruhe Zoo

Systematics
Order : Artiodactyla (Artiodactyla)
Subordination : Ruminants (ruminantia)
without rank: Forehead weapon bearer (Pecora)
Family : Giraffes (Giraffidae)
Genre : Giraffes ( giraffa )
Type : Reticulated giraffe
Scientific name
Giraffa reticulata
de Winton , 1899

The reticulated giraffe ( Giraffa reticulata ) is, according to the latest findings, an independent species within the genus of giraffes ( Giraffa ) and the giraffe-like family (Giraffidae).

features

anatomy

Reticulated giraffes can reach a height of up to 560 cm, a shoulder height of up to 330 cm and a weight of up to 900 kg. Despite their extremely long neck, giraffes - like almost all other mammals, including humans - only have seven cervical vertebrae . The neck is held at an angle of about 55 ° by a single, very strong tendon . The tendon runs from the back of the giraffe's head to the rump and is responsible for the "hump" between the neck and the body. At rest, this tendon keeps the neck and head in an upright position; to move the head down, e.g. B. to drink, the giraffe has to work hard. The neck has a standing mane along its entire length. There is a tuft of dark hair on the upper edge of the frontal bone cones. The nostrils are slit-shaped and can be closed. The tail tassel consists of strong black hair up to 0.5 m in length.

The front legs are longer than the rear legs so that the back line slopes down significantly towards the back. The extremely long bluish tongue with which giraffes scrape their food from branches is just as striking . It can reach a length of over 40 cm.

The small "horns" on the head of the giraffes are also striking. These are bone pegs that are covered with skin . Male giraffes use these horns in intra-species combat, which is why the upper edge of these bone cones is usually rubbed bare. In the female giraffes, however, dark tufts of hair can be recognized by these horns. In addition to the horns, male giraffes can also be distinguished from females due to their larger stature and their heavily ossified skull. In order to pump blood to the brain in sufficient quantities, the heart of reticulated giraffes is enormous at 12 kg. The heart can pump sixty liters of blood around the body per minute. The blood pressure is also significantly higher than in animals of comparable size.

Fur drawing

With the reticulated and Maasai giraffes , each individual has its own characteristic coat pattern, which distinguishes it from all other conspecifics. The fur is cream to ocher in color and has irregular speckled patterns that are separated from one another by thin white joints. This is where the name reticulated giraffe comes from. The color of the spots ranges from dark brown to black. The ventral side is lighter and not stained. The color of the fur pattern becomes darker with age.

particularities

The voice of the giraffes is rarely heard, it is described as bleating or grunting. The mother animal lures its young by squeaking. Giraffes communicate in the infrasound range, which is inaudible to humans, with frequencies below 20 Hz .

nutrition

Reticulated giraffes in the Samburu sanctuary in Kenya

The animals feed on acacias , myrrh, buds, young shoots, leaves and, in rare cases, grass. The giraffe grasps a branch or similar with its long, blue-colored tongue and strips off the food. A reticulated giraffe needs between 50 and 60 kg of food per day, depending on its size, in order to cope with this, herds roam large areas in search of food. Males spend around 43% of the day eating, females around 55%. All giraffes are ruminants . When ruminating, the food pulp from the reticulum must be transported back to a height of over 3 m into the mouth. This is achieved with the help of the muscular esophagus , which pushes the food portion upwards in a wave of contraction. This ever-increasing expansion and contraction of the neck can be observed well in ruminating giraffes. The fluid requirement is largely met from food, so that giraffes can go for weeks without drinking. If they do drink, they have to spread their front legs wide enough to lower their heads enough; they do the same when they take up food from the ground, which they do only under very unfavorable circumstances.

distribution

Savannas with umbrella acacias, thorn-bush steppes and light gallery forests are where the giraffes stay. They avoid dense forests, wetlands and terrain with steep slopes. However, most giraffes are found south of the Sahara , especially in the grass steppes of East and South Africa, in northern Kenya , southern Ethiopia and Somalia , and in protected areas . The populations north of the Sahara were eradicated early by humans and the increasing aridity .

Social behavior

Giraffes live either as solitary animals or in loose associations of adult cows, calves and young bulls. Adult bull giraffes are solitary animals that only approach the herds during the mating season . The bulls 'neck swinging' can be observed during mating and the associated battles of rank. The bulls swing their necks like clubs, with such force that a bull weighing around 1500 kg can lose its balance. The bulls' heads are protected by a double layer of bone.

Reproduction

Female giraffes can become pregnant for the first time around the age of five. After a gestation period of around fifteen months, they usually give birth to a single standing cub. Twin births are very rare. Since the females are ready to mate again two to three months after birth, they are able to give birth to a young about every one and a half years if the conditions are favorable. With a life expectancy of around twenty-five years, each female could theoretically give birth to twelve to fourteen young. On average, however, it should only be about half of this in the wild. The calf, which weighs an average of 70 kg at birth and is around 180 cm tall, has to endure a fall from a height of around 2.5 m before it is suckled by its mother for the next 9 to 12 months. Despite the protection of the mother, only 25 to 50% of the young reach adulthood.

Locomotion

Giraffes are passers-by , as indicated by the lack of a tension skin between the trunk and limbs. Giraffes can gallop in danger . In this gait, the front legs are thrown forward while the neck moves backward to maintain balance. When the front legs are set up, the rear limbs reach far forward beyond the front legs. In this way, giraffes can reach speeds of over 50 km / h. Due to the balance movements and the swinging of the legs, the giraffes gallop is a strangely swaying gait. The climbing ability of the giraffes is low. Relatively low embankments are an insurmountable obstacle for them. Giraffes don't like to go into the water. When lying down, the giraffes fold their legs, which are bent at the wrists and heels, under their torso. In this position, one hind leg is always slightly spread apart. On the run or when excited, giraffes turn their tail on its side so that it rests on the thigh.

Enemies

The most important hunter is the lion , while the danger from a cheetah or Nile crocodile is proportionally very low. Young animals, on the other hand, are also threatened by hyenas , leopards and African wild dogs . However, any predator runs the risk of losing their life if they attack a giraffe, because their size and the long, strong legs that giraffes use to kick and stomp can certainly keep a pride of lions in check and drive them away. Another dangerous enemy of the giraffe is undoubtedly the hunter. In the long term, the rapidly growing African population will displace the giraffes more and more from their traditional habitats.

Zoo keeping

The reticulated giraffe is the giraffe most frequently shown in German zoos (13 positions in 2017).

Individual evidence

  1. ↑ Julian Fennessy, Tobias Bidon, Friederike Reuss, Vikas Kumar, Paul Elkan, Maria A. Nilsson, Melita Vamberger, Uwe Fritz and Axel Janke, (2016): Multi-locus Analyzes Reveal Four Giraffe Species Instead of One in Current Biology, accessed on September 8, 2016
  2. ↑ Animal Documentary Reticulated Giraffe , Features, Retrieved January 23, 2013
  3. ↑ a b c d e f Wilfried Westheide, Reinhard Rieger (Ed.): Special Zoology . Part 2 edition. Gustav Fischer, Jena 1996, p. 625 .
  4. ↑ a b c d e f Anne Innis Dagg: Giraffa camelopardalis . Mammalian Species, No. 5, pp. 1-8 edition. The American Society of Mammalogists, 1971.
  5. ↑ a b Namibia-Jagdfarm  ( page no longer available , search in web archives )  Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice. , Retrieved January 23, 2013@1@ 2Template: Dead Link / www.namibia-jagdfarm.com  
  6. ↑ a b world of animals , Retrieved January 23, 2013
  7. ↑ Animal Documentary Giraffe , accessed January 23, 2013
  8. ↑ Animal Lexicon Switzerland ( Memento of the original from October 20, 2013 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. , Web giraffe profile, accessed on January 23, 2013 @1@ 2Template: Webachiv / IABot / www.tierlexikon.ch
  9. ↑ Markus Kappeler- Netzgiraffe Markus Kapeller, 1999, Netzgiraffe, published in the WWF Numisbrief Collection, accessed on January 23, 2013
  10. ↑ Reticulated giraffe in the zoo animal list, accessed on October 1, 2017.

Web links

Commons : Reticulated Giraffe  - Collection of images, videos, and audio files