The reason? In 1954, Goetz and Budtz-Olsen succeeded in measuring the arterial blood pressure in a standing, unanesthetize1'2 Id giraffe.n this animal, approximately 13 feet tall, the carotid arterial mean pressure … Besides, the walls of the dense blood vessels prevent leakage and expand and shrink to adjust to blood volume. At the same time, the animal's thick skin and an unusual muscle in the jugular vein—veins don't normally have muscles—add pressure to the vein, which carries blood from the head back to the heart. They are meant specifically to reduce the blood pressure before it enters the brain. 2. When a giraffe lifts its head, blood vessels in the head direct almost all of the blood to flow to the brain, and not to other parts of the head such as their cheeks, tongue, or skin. Otherwise, the blood that is pumped towards the brain at high pressure possibly may lead to brain damage. When the beast raises its head up for a bite in the trees, the blood drains out. The heart can … Luckily for the giraffe, nature has provided them with a complex pressure-regulation system that controls blood flow. 2. Understanding of these remarkable features is still relatively limited. Blood pressure had started to increase within two to three minutes of water consumption. Also, a series of valves located in the blood vessels that lead up the neck prevent the blood from flowing back to the heart in between beats. For a head 2 m above the heart, as it often is in giraffe, the hydrostatic pressure generated by the column of blood in the carotid artery is 2000 mm×1.055 (density of blood)/13.6 (density of mercury), which is … Prof. Graham Mitchell, Centre of Wildlife Studies in Onderstepoort, South Africa The giraffe has an extremely high blood pressure (280/180 mm Hg), which is twice that found in humans. This happens to us too. Visit our corporate site. It prevents the head from swelling when it bends over. Each Monday, this LiveScience series explores an amazing aspect of the world around you. If your blood pressure drops too low, not enough blood flows to your brain, and you can pass out. The blood pressure ranged between 260/160 mm Hg when … For their heads to reach the water, they must first spread or bend their front legs. With their high blood pressure, one would think giraffes should get a head rush when they bend down to drink from a watering hole. In older normal subjects, the average increase in blood pressure was 11 millimeters of mercury. So, one can imagine the enormity of these giant beings. A fully grown giraffe can raise or lower its head by up to 5m, so it might actually pass out were it not for a dense network of fine capillaries (the ‘rete mirabile’) that cushions its brain against rapid changes in blood pressure. There was a problem. Giraffe … Luckily, their anatomy is tailored to combat this very issue. There would then be a rapid increase over the next 15 minutes, before a blood pressure reduction after about an hour. That six-foot neck requires an intricate blood vessel system to maintain proper blood pressure between the heart and brain. Future US, Inc. 11 West 42nd Street, 15th Floor, But the harder pumping to get all the blood so far uphill results in high blood pressure. But thanks to the studies done, we have the answer now. In their brain, there are blood vessels that connect to the convoluted valves or blood sponge in the large neck veins. High blood pressure. Introduction. In just a second or two, a giraffe can lift its head from ground level to the sky, some 15 feet up, and never get a head rush. How the heart maintains the blood circulation in the giraffe’s legs was a constant thorn in many a scientist’s and researcher’s minds. The giraffe, when it lowers to drink, is also exposed to another risk: the brain in fact, when the giraffe lowers towards the ground, risks being exposed to a sudden increase in blood pressure, that could cause a collapse and cause it to fall passed out on the ground. Although the question of why such long neck and legs has been unknown, how the blood circulates, have been answered. This site uses Akismet to reduce spam. Learn how your comment data is processed. That net is called the rete mirabile, which is Latin for “wonderful net,” and it is made … ), Goetz concluded that, judging by human standards, giraffe should faint when they raise their heads after drinking water (Goetz, 1955).This conclusion followed a prior study by Rushmer et al. Yet, in less than two seconds, Mr. (1948) who had shown that blood pressure … And it works in reverse as well. Live Science is part of Future US Inc, an international media group and leading digital publisher. Based on the dimensions of a giraffe … Furthermore, if the giraffe were to get cuts, this thick skin and inner fascia would prevent blood pooling and excessive bleeding. Its feet are six feet long and its tongue 21 inches long. Giraffes tower and journey the savannas, grasslands, and plains of eastern and southern Africa. The layer of tight skin on its legs not only maintains pressure but also prevents the vessels from bursting. There are a few ways that it can achieve this. Giraffes have big hearts, weighing up to 26 pounds.