Written by: Ben Coley, head trainer at Bushwise
There is something so enchanting about the iconic giraffe. It is almost impossible not to lose oneself in its unusual rhythm, which has a hypnotic effect that causes most onlookers to develop a dumb expression of pleasure. How it manages to drift across the savanna with an almost regal elegance is rather baffling as it is in fact quite gangly and ungainly – not to mention grossly disproportionate from head to feet. Yet somehow, thanks to the miracle that is nature, the giraffe is a symbol of grace and fluidity.
The biomechanics necessary for such an animal to function efficiently are almost endless. Perhaps no other animal houses so much unique engineering beneath its mosaic-like pelt. Gravity is a giraffe’s biggest enemy. How do you pump sufficient blood up such a long neck and how do you avoid all the blood flowing into the feet way below? The answer to first conundrum lies in the heart. Whilst the giraffe’s heart is not much bigger than one would expect for an animal of this size, it is significantly heavier. This is due to the fact that the muscular walls of the left ventricle are up to 7cm thick and this is the engine that drives the giraffe’s circulatory system, producing an average blood pressure of 300/200 to maintain sufficient blood supply to the brain! The skin enveloping the legs is also incredibly thick and functions like giant compression socks to prevent the blood from pooling. In fact, fighter pilots’ G-Suits were modelled on this principle as it is so effective!
But perhaps the most fascinating of a giraffe’s physiology is the flexibility of its iconic neck. Despite housing the same seven bones as found in humans, the cervical vertebrae are hugely elongated, with each one being nearly 30cm long. Powerful muscles and a highly elastic nuchal ligament hold this incredible structure in place, and these adaptations, along with a heavy, club-like skull and dense ossicones (horns), provide the giraffe with a very effective weapon. Sexual selection was probably the driving force behind this bizarre arrangement and males will engage in bouts of ‘necking’ to determine dominance, and in turn, mating rights.
Do not be fooled however by its calming and charming exterior. The force generated by a giraffe swinging its neck is immense. The momentum and inertia are powerful enough to knock out an opponent, break bones and even cause death if the fights are serious enough! Despite its violent streak, the giraffe still manages to fight in perhaps the most beautiful display of aggression in the animal kingdom. To watch this veritable dance is akin to watching a performance of the Bolshoi Ballet Company. The necks flow in great arcs as the massive muscles generate enough power to deliver thudding blows that echo out across the plains. But it is their evasive skills that are the true highlight. They bob and weave like boxers, twisting their necks in seemingly impossible angles and directions as blows rain down. So basically imagine Mohammed Ali performing ballet and you will have a closer idea of what I am getting at!
Not all fights are this brutal, however, and young males will often spar for dominance in their social hierarchies. These ‘disagreements’ are not normally so violent but can still cause superficial injury. At birth, the ossicones atop the skull are made from cartilage, but over the years will ossify to become bone, and thus a more effective weapon. During their first few years, an exuberant fight may mean that one or both ossicones may be bent out of shape by the force of the impact and this will remain with them for life once the cartilage has hardened. Strangely, after a skirmish, male giraffes are often recorded mounting their rivals in what looks like a homosexual display. However, this is not that unusual in the animal kingdom, and is probably nothing more than a physical display of dominance from the winner to his defeated foe.
The students at Bushwise were privileged to watch such a fascinating scuffle between two young males, against the backdrop of the imperious Drakensberg Mountains, which culminated in this unusual behaviour. And it is their interpretation of iconic moments like this that they must master should they continue along their path to becoming highly qualified field guides.