The Fast Walking Camel Leopard Of Africa.

    The formal name for the giraffe is Giraffe cameleopardalis. The term Giraffe may have been stollen from the Arab word, zarāfah, meaning fast-walker. The famed taxonomist Linnaeus gave the giraffe its second name, meaning the “camel-leopard”, in 1758 because he thought they looked like a strange hybrid of the two animals with its long neck and spotted appearance. For many decades the giraffe has been recognized as a single species with many sub-species, isolated groups that have distinctive features such as pigmentation, behavior, or size. But recently, a group of researchers as set off a flurry of excitement following claims that these isolated populations represent distinct species, not just one unified species living in different places. There is not room within a blog post to address whether there is one, four, or 100 species of giraffe. This is best left to the scientists. But, because of all this recent attention many people are likely thinking about giraffes more than ever before. Below I briefly explore the natural history of giraffes below so that our readers can gain a deeper appreciation of their biology and natural history.

     Giraffes are distantly related to cows, pigs, sheep, goats, and other “even toed”

okapi_giraffe_neck
Both giraffe and okapi have seven cervical vertebrae in spite of their obvious differences in neck length.

mammals within the family Artiodactyla. Giraffes also chew a “cud,” (see a video here) which also places them within the family Ruminantia. This distinctive behavior helps them extract the maximum nutrient value out of their plant-rich diet. The giraffe is the largest living ruminant. Although the giraffe’s most distinctive feature is its size and long neck, its closest living relative is the short-necked, horses -sized okapi (appropriately nick-named the “forest-giraffe”). But even in spite of this striking difference in neck length, the okapi and giraffe have the same number of cervical (i.e., neck) vertebrae.

As I stated above, giraffe’s are spread across Africa as a series of distinct populations. They occur in the open savannah where they use their long necks to feed on the high leaves of acacia trees. Because of the distance and lack of suitable habitat between populations it is unlikely that these different populations ever come into contact with one another. Although the study I mentioned above used genetics to further support this idea, the only discernible difference between these populations are differences in their pigment patterns. Some populations have perfectly outlined, geometric patterns while others look like messy ink spots coving the hide of the animal. It has been also suggested that the giraffe’s spots are just like snow flakes, everyone is distinct.

genetic_subdivision_in_the_giraffe_based_on_mitochondrial_dna_sequences-brown-2007
Geographic distribution and variation in pigment pattern of giraffe (sub)-species. Reproduced from Brown et al. 2007.

Within the United States giraffes are found in many zoos, including the Jacksonville Zoo in Jacksonville FL where the above picture at the top of the page was taken. They tend to be gentle animals that interact well with humans. (I’ve lost track of the number of times my six- and two-year-old sons have fed giraffes now. A visit to the giraffe enclosure is always a top attraction for us.) In captivity a giraffe can live over 30 years, compared to 15-25 years in the wild. The largest difference in lifespan is likely due to the lack of predators roaming the zoo enclosures. Even in the wild giraffes are often found in relatively large groups so maintaining multiple individuals in a single enclosure is not likely detrimental to the animals as long as their is enough space to move and food to eat. In the wild a group of giraffes, called a tower, may reach up to 44 individuals! Giraffes may even hum to one another at night to help maintain cohesiveness of the group, although the precise meaning of the hums between individuals is not yet known. But don’t sneak into the zoo at night hoping the hear giraffes! Their sounds are barely detectable to the human ear.

Whether there is one species of giraffe or four does not impede our ability to be impressed by the mighty fast, savannah walking camel leopards of Africa. The next time you visit the Brookfield Zoo of Chicago or many other zoos around the world be sure to stop and observe these gentle animals.

 

 

 

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