There are nine subspecies of giraffe. The West African giraffe is very endangered, with only 220 remaining in the wild. The Thronicroft giraffe, not pictured on the map below, has leaf-shaped spots extending to the lower leg and there are no more than 1,500 remaining in the wild. Fewer than 700 of the Rothschild's giraffes are thought to remain in the wild. The Kordofan giraffe, not pictured below, has small irregular patches that do not extend to the lower legs and has no more than 3,000 members remaining in the wild. The Nubian Giraffe, also not found below, has large, four-sided patches with no spots on the inner sides of the legs or below the hocks. There are less than 250 of these Nubian giraffes left in the wild.
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| As you can see, I am most likely to see the South African Giraffe while I am at Kruger! |
A fully grown giraffe is normally between 16 and 20 feet tall. Males usually weigh around 2600 pounds and the females around 1800 pounds. Each giraffe has a unique coat pattern serving as camouflage that blends in the savanna woodlands. These unique patches may also serve as windows for thermoregulation, acting as sites for complex blood vessel systems and large sweat glands. Their fur is full of parasite repellents that give the animal a characteristic smell. In fact, there are at least eleven smelly chemicals in the fur. The tail has a tuft of long, red hair that is used to swat flies away. Its large eyes are located on both sides of the head and bulge outward, and give the giraffe good all-around vision from its rather high vantage point. They are capable of seeing in color, and they can open and close their nostrils in order to protect them against sandstorms and against the ants that inhabit the trees it feeds on. A 20 inch tongue is purplish in color, and useful to protect against sunburn and to clean the animal's nose.
Both males and females have prominent horns formed from ossified cartilage that are covered in skina and fused to the skull at the parietal bones. The horns of females have tufts of hair on top, and those of males are larger and tend to be bald on top. There is also a median horn at the front of the skull, which is more developed in males.
Like hyenas, the front legs of a giraffe are longer than its hind legs. When it comes to locomotion, the giraffe has only two speeds: walking and galloping. Walking involves moving the legs on one side of the body at the same time, and then the legs on the other side. When galloping, the giraffe's front and hind legs work in pairs. As unlikely as it may seems, the giraffe can actually get up to 37 mph. With each step, the giraffe swings its head. And if you've ever wondered if a giraffe can swim, it's your lucky day. It is assumed that giraffes are unable to swim because their legs don't work in that nice rotational manner that is involved with successful swimming. No one has ever really seen a giraffe swim, so no one knows for sure. Quite frankly, it's not a useful skill for the giraffe anyways because it is likely to be taller than the depths of the streams and rivers it encounters.
The neck of the giraffe by itself can be up to 6 feet 7 inches long. This long neck results from the lengthening of the cervical vertebrae. This means that the giraffe DOES NOT have additional vertebrae to make its neck so long...it just has bigger bones! The reason why the giraffe has a hump on its back is because the head and neck are held up by large muscles and ligaments that are anchored to large dorsal spines under that hump. The older the giraffe, the heavier the skull tends to be.
The giraffe has to have a special circulatory system in order to manage its great height. Its heart can weigh more than 25 pounds and measures up to 2 feet long, and must generate approximately double the blood pressure required for a human to get blood to the brain. Its jugular veins contain several valves to prevent blood from flowing back into the head when the head is lowered. Its legs have a layer of thick tight skin that prevents too much blood from flowing into them.
Giraffes like to live in savannas, grasslands, and open woodlands, although the Angolan giraffe is known to inhabit desert environments. They browse on the twigs of trees, taking a particular interest in Acacia trees, Commiphora trees, and Terminalia trees. A giraffe likes to eat about 65 pounds of leaves and twigs daily, but can survive on only 15 pounds. It is a ruminant, so it first chews its food, then swallows it for processing and then passes the half-digested cud up the neck to chew again. Giraffes are natural gardeners, delaying the growth of young trees and giving an hourglass shape to taller trees.
Giraffes are usually found in fluid groups and have few strong social bonds. Adult males tend to be solitary, but calves and subadults are rarely on their own. Giraffes are able to walk and run within a few hours of birth. A newborn giraffe is already about 6 feet tall. Mothers with calves gather in herds consisting of two or more infants and juveniles and their mothers. These nursery herds are maintained by the bonds formed between the calves, and adult males play almost no role in raising the young. In males, necking is used to establish dominance and can occur at low or high intensity. In low intensity necking, the combatants gently rub their heads and necks together and lean against each other. The male that can hold itself more erect wins the bout. High intensity necking involves combatants spreading their front legs and swinging their necks at each other while attempting to land blows with their horns. The heavier the skull, the more powerful the blow.
Healthy adult giraffes pretty much are safe from predation because they can defend themselves with powerful kicks. However, in Kruger National Park (!!!), lions have been known to prey on adult giraffes. On the other hand, calves can fall victim to lions, leopards, spotted hyenas and wild dogs.
CHEETAH TIME!!!
Cheetahs are the only cats that, while sprinting, can turn in midair to follow their prey. (Found on Sand Diego's Zoo site). It the picture below, the prey isn't really prey, but an unlucky sibling.
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