The giraffe is an African even-toed ungulate mammal, the tallest living terrestrial animal and the largest ruminant. The giraffe is also noted for its extremely long neck and legs and prominent horns. It stands 5–6 m tall and has an average weight of 1,200 kg for males and 830 kg for females.
Similar species: Even-toed Ungulates
By aardvarkzw
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Uploaded Jun 9, 2014. Captured in Mosi-Oa-Tunya, Zambezi National Park, Zimbabwe.
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Posted 11 years ago"Happy World Giraffe Day! As the world’s tallest animal, giraffes can easily browse heights that other herbivores cannot reach. Within seconds, a giraffe can raise its head from ground level to the tree canopy, some 5.5 meters high (18 feet), and never get a head rush! Pretty cool, but having a super long neck creates many challenges for blood circulation as it creates an awfully long journey for blood to flow from the heart to the head. Why don't giraffes faint or end up with brain damage every time they bend over to get a drink? Giraffes have several unique features to deal with these challenges.
First, they have very tight skin on their necks and legs, which acts like natural compression socks to keep blood moving. In addition, they have a super cool safety net at the base of their brain, called a rete mirabile. When a giraffe bends down, the rete mirabile acts like a sponge/net by collecting any extra blood that travels to the head. This lowers blood pressure, thus controlling blood flow to the brain. When the giraffe raises its head back up, the rete mirabile pushes out the blood that it was holding so the giraffe doesn't pass out on its way back up. Next, giraffes have very large, powerful hearts. Your human heart is about the size of your fist. A giraffe's heart is about 60 cm (2 ft) long and weighs more than 11 kg (25 lbs)! Its heart can pump 16 gallons of blood per minute! Incredible! Giraffes also have special valves in the major veins of the neck, which automatically close when a giraffe bends down and then open when it lifts its head back up. This significantly helps to reduce the pressure in its head and counteracts the influence of gravity. Extra thickness and elasticity keep the blood vessels from rupturing under all the pressure.
It takes ALL of these features to work together just for a giraffe to bend down to get a drink of water and then raise its head back up! If the giraffe's heart wasn't strong enough, blood would never reach its brain, and it would die. If the valves in the neck didn't open and close, too much blood would rush to its brain, and it would die. If it didn't have the rete mirabile, its brain would be severely damaged, and it would die. Giraffes are truly remarkable animals! {Northern Giraffe (Giraffa camelopardalis) spotted in Zimbabwe by JungleDragon user, aardvarkzw}" Posted 7 years ago
Today is unusual ‘creature features’ Day 3! #JungleDragon
To see more wildlife with unique features:
RETE MIRABILE
Within seconds, a giraffe can raise its head from ground level up to the tree canopy, some 5.5 meters high (18 ft)! Why don't they faint or end up with brain damage every time they bend over to get a drink? Part of the reason is that they have a structure in their brains called a rete mirabile. When a giraffe bends down, the rete mirabile acts like a sponge and soaks up any extra blood that is traveling to the head. This lowers blood pressure, thus controlling blood flow to the brain. Then, when a giraffe raises its head back up, the rete mirabile pushes out the blood that it was holding so the giraffe doesn't pass out on its way back up. The rete mirabile, in conjunction with a large, powerful heart, ‘compression sock’ skin, and valves in its neck, keep giraffes alive. Without all these parts working in conjunction, giraffes would be dead. {Northern Giraffe (Giraffa camelopardalis) spotted in Zimbabwe by aardvarkzw} #Giraffe #ReteMirabile #Giraffacamelopardalis
https://www.facebook.com/jungledragonwildlife Posted 4 years ago