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Hit enter to search or ESC to close. Close Search. When they're bent over, it is easier for a predator, like a crocodile, to grab hold of the giraffe.
So, giraffes go to a watering hole together and take turns watching for predators. If water is easily available, they can drink 10 gallons 38 liters a day. When a giraffe baby, called a calf, is born, it comes into the world front feet first , followed by the head, neck, and shoulders. Its entry is like a slow-motion swan dive! Because the umbilical cord is only about 3 feet 1 meter long, it breaks midway through the birth, allowing the newborn to drop to the ground.
The fall and the landing don't hurt the calf, but they do cause it to take a big breath. The calf can stand up and walk after about an hour, and within a week, it starts to sample vegetation. Sometimes the mother leaves the calf alone for most of the day. The youngster sits quietly until she returns.
When a calf gets older, the mother leaves her youngster together with other calves in a "nursery. In the nursery, the calves develop physical and social skills through play. Under the watchful eye of the designated babysitter, the youngsters explore their surroundings throughout the day. The young giraffes can eat leaves at the age of four months, but continue to nurse until they are six to nine months old. In many African countries, giraffe populations are slowly decreasing because of habitat loss and the overgrazing of resources by livestock.
As a result, the future of giraffes is dependent on the quality of the habitat that remains. While it has historically lived in western Kenya, Uganda, and southern Sudan, the Uganda giraffe has been almost totally eliminated from most of its former range and now survives in only a few small, isolated populations in Kenya and Uganda. The Nigerian giraffe is found in just one area of Niger, and it is considered the rarest of the giraffes. The population of reticulated giraffes G. They are no match for humans with guns; giraffes are shot or snared for their meat, hide, bone marrow, and tail hair.
Kenya is starting a giraffe conservation program for the three subspecies found there: reticulated, Uganda, and Masai giraffes G. San Diego Zoo Wildlife Alliance supports a community conservation effort in northern Kenya that is finding ways for people and wildlife to live together.
And in March , another research group reported giraffe-specific variants in genes involved in fibrosis. And the giraffe has another trick to avoid heart failure: The electrical rhythm of its heart differs from that of other mammals so that the ventricular-filling phase of the heartbeat is extended, Natterson-Horowitz found.
Neither of her studies has been published yet. This allows the heart to pump more blood with each stroke, allowing a giraffe to run hard despite its thicker heart muscle. Natterson-Horowitz is now turning her attention to another problem that giraffes seem to have solved: high blood pressure during pregnancy, a condition known as preeclampsia. In people, this can lead to severe complications that include liver damage, kidney failure and detachment of the placenta.
Yet giraffes seem to fare just fine. Natterson-Horowitz and her team are hoping to study the placentas of pregnant giraffes to see if they have unique adaptations that allow this. People who suffer from hypertension are also prone to annoying swelling in their legs and ankles because the high pressure forces water out of blood vessels and into the tissue.
But to a cardiovascular physiologist, there's even more to love. Giraffes, it turns out, have solved a problem that kills millions of people every year: high blood pressure. Their solutions, only partly understood by scientists so far, involve pressurised organs, altered heart rhythms, blood storage — and the biological equivalent of support stockings.
Giraffes have sky-high blood pressure because of their sky-high heads that, in adults, rise about 6m 19ft above the ground — a long, long way for a heart to pump blood against gravity.
It doesn't faze the giraffes, but a pressure like that would cause all sorts of problems for people, from heart failure to kidney failure to swollen ankles and legs. In people, chronic high blood pressure causes a thickening of the heart muscles. The left ventricle of the heart becomes stiffer and less able to fill again after each stroke, leading to a disease known as diastolic heart failure, characterised by fatigue, shortness of breath and reduced ability to exercise.
This type of heart failure is responsible for nearly half of the 6. Giraffes maintain extraordinarily high blood pressure, and yet it doesn't seem to cause them health problems Credit: C. When cardiologist and evolutionary biologist Barbara Natterson-Horowitz of Harvard and UCLA examined giraffes' hearts, she and her student found that their left ventricles did get thicker, but without the stiffening, or fibrosis , that would occur in people.
The researchers also found that giraffes have mutations in five genes related to fibrosis. In keeping with that find, other researchers who examined the giraffe genome in found several giraffe-specific gene variants related to cardiovascular development and maintenance of blood pressure and circulation. And in March , another research group reported giraffe-specific variants in genes involved in fibrosis.
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