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Journalism of Courage
We invented the wheel but Mother Nature evolved legs. No living creature evolved wheels because for all of them (excepting us) legs were perfect for the purpose for which they were designed and better than any 4WD system we might have designed.
Elephants may weigh up to five or six tons yet can charge at you at 40 kmph, faster than you can run! Their legs are straight, solid, column-like structures and they are said to have 4-leg-drive in that both their fore and hind legs provide thrust – and braking. Most other animals have only ‘rear leg-drive’ , the rear legs providing thrust and the front ones braking. Elephants can move in near silence (no 4WD can) because their feet have in-built shock absorbers.
Most of their weight is borne and cushioned by the tips of their toes, and the fibrous fatty pads under their heels. For additional grip, the sides of their feet are pitted and ridged enabling them to be very good climbers over rough terrain – and each elephant is thought to have its own custom design of ridges – rather like our fingerprints. African elephants have five toes with four toenails on their front feet and three on the rear. Asian elephants have five in the front and four at the rear. In addition to locomotion, elephants use their legs to dig for water and to pick up seismic signals from the ground – the far-away thump of other animals’ especially, elephants’ footsteps.
That other heavyweight, the rhino (weighing over 3.5 tons) , has by contrast much thinner legs than the elephant yet can move with all the delicacy of a very big ballerina and they can swivel on a dime. Their feet are more like those of horses and, amazingly, their weight is distributed in such a way that their three ridged toes only feel a peak pressure of 75 pounds per square inch (psi), not much different from ours. The pads on their feet splay out as they land. We are still trying to figure out how rhinos manage to move with the grace and speed they do, in spite of their clumsy bulk.
Depending on your point of view (researchers seem divided over this) kangaroos may have either three or five legs – but never four! There are of course the two massively powerful hind legs with which they hop – at more than 48 kph, and the tail, which some count as the third leg because it is used for propulsion when the kangaroo grazes, as well as the two small front legs (which some consider to be ‘hands’) on which it rests while feeding, while pushing itself forward by its tail. The massive hind legs, which serve as launch pads are also used in kick-boxing and a swipe from that muscle-packed tail can cause serious damage. A kangaroo may also thump its hind legs on the ground to indicate the presence of a predator.
Ibex, bharal, big-horn sheep and their ilk who spend their lives on near vertical, rugged mountain slopes are the envy of any climber – and no 4WD vehicle can come anywhere close to them. They are ‘cloven-hoofed’ which enables them to get their tenacious grip on near vertical slopes. Antelope, buffalo, impala and gazelle have four toes on each foot, but stand tiptoe on the two central toes – their hooves – which gives them speed and the ability to stand taller, the easier to spot predators. A hoof is really just a hard protective covering (like a nail) for the animal’s toes.
Springbok antelopes often do consecutive pogo-stick take-offs of up to two meters, an exercise called ‘prinking’, with their backs arched and heads lowered. We haven’t figured out exactly why but can only imagine the kind of energy (and maybe joie-de-vivre!) it takes to pull this off!
Horses are mainly ‘rear-leg’ drive with the hind legs providing power and thrust and the front legs braking and bearing the weight of the animal. They have what is called a ‘suspensory apparatus’ which bears the weight, prevents over-extension of the joints and absorbs shock, as well as a ‘stay’ apparatus which locks the major joints in the limbs enabling horses to stand for hours on end and even sleep standing.
The cheetah – with a 110 kph top speed and quicker acceleration than a Ferrari – is the fastest land mammal and is built for speed. Small, streamlined, lightweight, its long legs, feet and spine are flexible, the legs containing spring-like ligaments. Like a horse, the cheetah can race with all four feet off the ground – either stretched ahead and behind it or crossed under it, as it races after prey, and in full flight is for the most part airborne.
It has quick response ‘twitch’ muscle fibers to provide it with the instant burst of power it needs (20 per cent more than those of greyhounds or racehorses) but these exhaust quickly and the burst is all but over in 300 meters. The cheetah has semi-retractable claws, which provide grip like those of spiked shoes and the ridges on its pads act like the grooves in a tire.
Our wheels may speed us over specialized smooth surfaces (we call them roads!) but over natural, especially rugged terrain, most animals will beat our vehicles hands down. Even in a Formula 1 race, tires are frantically changed as the track conditions change during the course of a race. You will never see an animal stop to change its hooves, if say it suddenly starts raining and becomes muddy! There are many other species, with specialised legs and feet, some of which we shall meet in the next column. So far, it’s Legs 1, Wheels 0!
