More on Elephants
The general term for an elephant is Aliya in Sinhala and Anai in Tamil. In Sinhala, a tusker is called an Atha and a male without tusks an Aliya. A male without tusks or tushes is also called a Pussa. Athinne is the term for a female with tushes and Alidena is a female without tushes. In Tamil, a tusker is called Komban.
Elephants are exceptionally well co-ordinated and intelligent animals. Learning and growing as family groups is a part of the elephant’s life. Most of the elephant’s habits are learnt and not instinctive.
Elephants have small eyes and their field of vision is limited. They cannot see beyond 30 metres unless the object is large and erect. Their eyes are easily dazzled in the open but their vision improves in the shade of the forest. However their senses of smell and hearing are very well developed. It is of course necessary for the elephant to be downwind to pick up any sounds or scents.
Other than their normal vocalizations like trumpeting, growls and rumblings, it is believed that elephants can communicate with each other over long distances using low frequency sounds (infra-sound), which are below the limit of human hearing.
The elephant, when alerted, points its ears forward and turns in the direction of the sound to catch the sound waves in its large ears. It has been observed very often that two or more elephants which are far apart, suddenly with no audible communication, get into action to do the same thing like cross the road or approach an intruder. Here it is evident that their communication is through infrasound.
Teeth, tusks and tushes
Tusks are an elongation of an elephant’s incisor teeth. Tushes are small tusks that protrude just beyond the lips. Only some of the males in the Asian elephant have tusks. In Sri Lanka, about 7% of the males have tusks. In the African species, both the male and female have tusks.
Almost the entirety of an elephant’s tusk is composed of ivory, though it is not completely solid. The end of the tusk has an enamel conical cap, which often wears away. Nearly all elephants are born with a pair of deciduous milk tusks or tushes, which are around two inches in length. These tushes are shed by the time the elephant is one and a half years old. In some of the males the milk tusks are replaced by the long tusks that we see.
Though tusks and tushes are not used to masticate their food, some elephants use their tushes to break off branches and twigs and, as a result, most tushes are worn, chipped or broken. Some tushes are visible whilst others are covered by the upper lip. Tusks continue to grow throughout the lifetime of the elephant.
Elephants have tusks of different sizes and shapes. The weight of a tusk in a Sri Lankan elephant is generally around 30 kg. Most elephants have a symmetrical pair of tusks. However, in some cases there are differences in the thickness or length in a pair of tusks on the same elephant. Tusks differ in colour, from ivory white to dull white and almost beige.
Some tusks are brittle and it is not unusual to see an elephant with one or both tusks broken. In quite a few instances, the tusks do not grow parallel to each other and cross at their extremities. There are also many records of single tuskers.
The only other teeth that an elephant has are its molars. These large teeth are grooved across their surfaces. The number of ridges varies with age and it is possible to estimate the age of an elephant by examining its teeth. I have given details of an elephant’s molars in my first article.
The large ear lobes of the elephant help to catch sound waves to make the hearing of the elephant more acute, especially when the animal is in downwind.
There are variations in the size of the ears of elephants that are the same age. The shape of the ears of elephants also varies. These variations can be observed among the animals within a herd or even a family unit. The ears of most wild elephants are scarred or damaged in some way. Some are torn; others have pieces taken off and some have holes.
These damages are results of fights with other elephants and may be damages during flights through thick jungles. Even though the elephant’s ears are ragged as a result, this does not affect its thermo-regulatory system as long as the muscles can continue to control the movement of the ears.
Elephants stand with their backs to the wind, so that it blows on to their outspread ears and cool the blood vessels. If there is no wind, the elephant flaps its ears. In times of drought or intense heat, I have observed elephants, both tame and in the wild, sometimes drawing water from inside their throats and splashing it on their ears.
The objective is the same - to cool itself through the blood vessels in its ear flaps. This effort at cooling itself is called thermo-regulation. Elephants have thick skins and have no pores to sweat through and cool themselves.
With the passage of time, the top of an elephant’s ear lobe, which is straight at birth, rolls over. The approximate age of an elephant can be judged by the roll of its ear lobes. By the time an elephant reaches the age of twenty five to thirty years, about 2.5 cm of the ear has rolled over in the intervening period. This rolling of the ear increases by about 1 cm over the next five years. When an elephant is about sixty years of age, the ear has turned over about 5 cm at the top.
Trunk and tail
The trunk of the elephant, which is a prehensile elongation of its upper lip and nose, with a finger-like prehensile extremity, is that part of its anatomy, which popularly characterizes the elephant. The lower lip, compared to the trunk, is much shorter. However it projects some distance forwards and downwards. The trunk is the most versatile part of an elephant’s anatomy.
It is made up of thousands of tiny muscles and has no bone or hard tissue. The trunk is dexterous and able to perform various functions because of its high degree of flexibility and manoeuvrability. The trunk is used by the elephant as a hand or arm and even as a weapon.
The tip is sensitive to both touch and taste. An elephant can even pick up a coin from the sand with its trunk and hand it to its mahout seated on its back. The trunk is used to gather food, grass leaves and branches, and to put them into its mouth.
To drink, it sucks up water and squirts it back into its mouth. The elephant uses its trunk to ward off danger or to attack enemies. The trunk is used to blow water, sand and mud onto its body. When swimming, the trunk is kept above the water like a snorkel.
On the other hand, an elephant can kill a bull with a single swipe of its trunk. During times of drought when water is difficult, elephants dig up the riverbed with their forefeet and trunks in search of water. The elephant uses its trunk to communicate. It trumpets in anger, fear and joy. The trunk is also used to touch elephants from other herds when they meet and also in courtship.
The tail of an elephant varies in length. The tail has a tuft of bristles at the end. Generally a tail reaches three-quarters of the way down to the ground, one that touches the ground being rare. The thick, hard bristles at the end of the elephant’s tail are on the anterior and posterior sides of the tail and not all round. Elephants with short tails are encountered very often.
In most of these instances, the tail has been broken off in a fight, where the tail of a retreating elephant is grasped by the other with its trunk and due to the fragility of the tail, it is broken off.
The skin of an elephant, is thickest on the hind limbs and hindquarters, thinner on the forelimbs and shoulders, and is thinnest on the inside of the ears.
Though the elephant’s skin seems to be tough, it is sensitive in certain areas and susceptible to the ravages of heat and insect pests.
The colour of the skin is dark greyish over most of the body but lighter on the head, trunk and ears. However depending on different circumstances, elephants are seen in different colours. If an elephant is just out of water that is clear, the skin is dark grey. If the water that it has been in is muddy, the skin takes on that colour.
If the elephant has powdered himself with dust or sand, the colour of the skin can vary from a rust colour to brown. If it has thrown dust from clay soils onto its body, the elephant’s skin takes on a light grey colour.
An elephant picks up sand with its trunk and dusts its body with it. Sand baths generally follow a bath in water.
Mud and sand bathing is generally followed by the elephant rubbing itself on an ant hill, rock or tree to rid itself of parasites that go off with the caked mud.
The surface area of the elephant’s skin is relatively small compared to the volume of the body. This causes a problem of heat dispersal. An elephant has no sweat glands and its body tends to get over-heated easily. Elephants cool themselves by several methods. The large ears, which have an intricate network of blood vessels beneath the skin, have a thermo-regulatory function as mentioned earlier. The constant fanning of the ears helps to lower the temperature of the blood through evaporation and loss of heat.
Limbs and locomotion
The four large columnar legs are necessary to support the massive weight of the elephant’s head and body. The limbs of an elephant are very flexible and enable the animal to run, walk fast, amble at a leisurely pace or climb up and down fairly steep slopes.
The elephant however cannot leap, trot, gallop or canter. An elephant cannot run at speed for long distances. When frightened, an elephant erects its tail and runs away. When angry it charges with its trunk in its mouth to protect this sensitive organ and the large ears are pinned against its head.
Elephants are very sure-footed in any terrain despite their bulk and clumsy appearance. They can negotiate rough slopes and walk along rocky ridges easily. Elephants generally walk in single file through thick forests making trails, which they use regularly.
They are sensitive to the contours, and as a result, many of our early engineers have constructed roads, along elephant trails. This helps to make an easy ascent along the road. A good example is the Bulutota Pass in Rakwana.
The elephant is the only mammal, which does not have a hock or joint in the hind leg where a knee should be. The Valaliya or marsh elephant, found off Manampitiya, has a broader sole to its feet to enable it to move about easily in the soggy conditions underfoot.
Three feet are always in contact with the ground to carry the weight of the body. When walking, the hind foot occupies the place just vacated by the fore foot, so that there is overlapping of fore and hind feet in a pacing elephant. On an average an elephant weighs about four tons.
The soles of its feet are compressible to take its great weight especially in uneven terrain. Pads on the sole of the elephant’s foot expand when on the ground and its weight put on it. When the weight is taken off the pads contract.
A fairly accurate way to gauge the height of an elephant is to double the circumference of the forefoot which is equal to its height at the shoulder. This, however, does not hold good for immature animals. The average height of the adult Sri Lankan elephant is 2.75 - 3 m.
The lifespan of an elephant is similar to that of man. They live to around 60 - 75 years. Early writings, however, claim that elephants have lived to over 150 years. Though Dutch records show that elephants have lived to over 100 years, such high figures may be due to the fact that, in a number of instances, elephants have been given the same name and performed the same tasks, with no record of whether it was a single elephant or more than one animal.
For instance, an elephant named Hurathalaya in the Dutch fort in Colombo is said to have lived for over 140 years. It is more likely that there was more than one elephant by the same name.
Elephants continue to grow through their lifetime. Each elephant, if observed closely, has its own features and characteristics. Its growth is not always uniform. There are significantly varied growth rates in different animals even from the same herd and family as is seen even in human families.
By Jayantha Jayawardene
May 7, 2007