Community Magazine April 2013

Unique Traits A couple of unique traits of the giraffe that are not visible on the surface involve its heart and circulatory system. Ahuge heart - as well as a very high blood pressure - is necessary in order to pump the giraffe’s blood all the way up to its head. In fact, the giraffe has the largest heart in the animal kingdom, measuring two feet long and weighing about twenty-five pounds! The giraffe’s special heart is able to produce the necessary high blood pressure for the giraffe. But there’s more to the wonder involved in this. When the giraffe drinks, its head is suddenly lowered seven feet below the level of its heart...and then, a few seconds later, it might be lifted back to nearly twenty feet into the air! These implications should be devastating. When its head is lowered that quickly, the giraffe should be stricken with a brain hemorrhage, the result of a huge rush of blood to its head. Conversely, the rapid raising of its head should drain all the blood from it, causing immediate unconsciousness. The fact that neither happens is the result of a specially designed valve which instantly and effectively controls the blood supply, to preventthedramaticfluxesinpressurefromknockingoutitsowner. In its upper neck, a complex pressure regulation system called the rete mirabile prevents excess blood flow to the brain when the giraffe lowers its head. When the blood supply begins to get full, the pressure is felt by the giraffe in time for it to right itself. Then the process works in reverse; the veins and valves partially close off, so blood doesn’t flow back down into the giraffe’s body too rapidly. Humans do not possess this special valve, as they have no need for it. The giraffe, however, could not survive without it. The degree of sophistication found in the giraffe is further testimony of the work of a Master Designer, and publicizes the greatness of Hashem and the brilliance of His creations. The Giraffe Wild World of Exploring ANIMALS the The giraffe is a gorgeous and gentle creature that stands out among animals like a skyscraper among buildings. Typically, these fascinating animals roam the open grasslands in small herds. Thanks to their towering legs and long necks, giraffes are the world’s tallest mammals. A male giraffe can grow to be eighteen feet tall. The giraffe’s height helps it keep a sharp lookout for predators across the wide expanse of the African savanna. Giraffes are so big that they do not need to hide frompredators. Besides humans, they are hunted only by lions and crocodiles, and their speed helps them escape from these predators. The long legs (six feet long) of the giraffe allow it to run as fast as 35mph. 78 COMMUNITY MAGAZINE