Giraffe possess a long neck that serves various essential roles and functions:
Neck Structure: Remarkably, despite its exceptionally long neck, a giraffe has the same number of vertebrae in its neck as humans and other mammals – seven cervical vertebrae. However, each vertebra can be around 25 centimeters long, providing giraffe with their distinctive long necks.
Feeding: Equipped with its long neck, a giraffe can effortlessly reach high foliage, fruits, and flowers in Vachellia or Senegalia trees (previously known as Acacia) and other sought-after species. This unique adaptation enables giraffe to exploit a range of vegetation that is beyond the reach of most terrestrial browsers, except for elephant. Their 45-centimeter-long tongue, combined with a specialized atlas-axis joint that permits the head to extend vertically, further enhances this height advantage. Giraffe feed primarily on broad-leaved deciduous foliage during the rainy season and evergreen species during other seasons.
Necking: Bull giraffe, and occasionally cows, engage in an intricate, often ritualized fight known as “necking” to establish dominance. They repeatedly swing their long necks, delivering powerful headbutts to their rivals’ bodies and underbellies. The reinforced skull usually absorbs the force of these blows, but such encounters can also result in unconsciousness or in rare instances even death.
Lookout Function: The giraffe’s height transforms it into a tall “sentinel” providing it with an elevated vantage point to survey the vast expanse of the African savannah, keeping a watchful eye for potential predators.
Blood Supply System: The giraffe’s heart, which can weigh up to 11 kilograms, must generate nearly double the normal blood pressure of other mammals to maintain blood flow to the brain against the force of gravity. In the upper neck, an intricate pressure-regulation system known as the “rete mirabile” prevents excessive blood flow to the brain when the giraffe lowers its head to drink. Conversely, the blood vessels in the lower legs experience significant pressure due to the weight of fluid pressing down on them. In most animals, this pressure would result in blood seeping out through the capillary walls. However, giraffe have a tightly fitted sheath of thick skin over their lower limbs, similar to a pilot’s G-suit. This unique adaptation helps maintain high extravascular pressure, preventing fluid leakage.