The only extant (living) species in the Order Proboscidae are the elephants. The order, however, includes a number of other now extinct species. The earliest record of a member in this group was a small pig-like creature called Moertherium. It lived in a swamp area in what is now modern day Egypt some 50 million years ago. There were a number of other species like it who in turn evolved into the Woolly Mammoths and Imperial Mammoths.

Recently, there has been much debate over the status of the Forest elephant, which is found in West and Central Africa. Originally classed as a sub-species of the African elephant, new research has indicated that the two may in fact be separate species, and has been give the provisional name Loxodonta cyclotis. The African elephant and Forest elephant are morphologically different and exhibit different social behaviourisms but these differences were previously ascribed to a physical adaptation to different habitats.

Genetic research has indicated that the differences at the cellular level between the two sub-species may be significant enough to recognise two distinct species. The debate is yet to be resolved, but as at October 2004 this race of elephant has not been given individual species status.

The scientific name for the species, Loxodonta africana is derived from ‘loxos’ which means lozenge, and ‘donta’ meaning tooth. This a reference to the lozenge shaped ridges of the animal’s molar teeth.

Description

The African Elephant is the largest land mammal, with mature bulls reaching a record weight of 7 tons (15 400 lbs.). Elephant cows average two and a half metres tall and three tons. Both sexes have tusks. Sexing elephants is not easy, but a few differences other than size may be apparent. During periods of heightened sexuality males may exhibit a large wet area on the side of their heads from a large gland. Females seem to have a more convex rounded forehead than the males.

The height of elephants can be roughly calculated from their footprints, as twice the circumference of their front foot gives their approximate shoulder height in normal habitat, this is however, not a hard and fast rule. Elephant are also known as pachyderms, this word is derived from the Greek pachy = thick and dermis = skin, due to the fact that it may be more than 3cm (1 in.) thick in places, specifically their legs and rump.

Statistics

Food and Eating

Elephants are both browsers and grazers, utilising a very wide range of plants. Ecologists now classify them as mixed feeders, a term also applicable to impala and eland. Grasses are most often taken just after a rainy season, with trees and browse (leaves) making up the majority of their diet.

Over 90 different tree species are utilised by elephant, although the Mopane tree (Colophospermum mopane) seems to be highly favoured. When eating off a tree, the leaves as well as bark and occasionally the roots are taken. This often has a real detrimental effect on the tree, especially when a whole tree may be pushed over just to reach the choice new growth in the canopy. Thus when elephant populations exceed their ecological carrying capacity large areas of woodland may be severely damaged.

Eventually this will impact on their numbers, but the destruction is first felt by lesser browsing species such as antelope. However, in areas where severe bush encroachment has taken place, especially by Mopane, the elephant are quite beneficial, improving the habitat by opening up dense woodland for other species.

Elephant are not very efficient feeders, not only in their physical taking of vegetation, but also digestively. In fact elephants only digest some 40 % of what they eat, and being of such immense size, they require at least 170 Kg (470 lb.) of plant matter daily. Elephants are also highly dependent on a stable water supply, drinking up to 160 litres (42 gallons) of water per day.

Social Behaviour

Elephants are organised into a number of social groups. The first and most common are large herds led by a matriarch. This consists of a related group of females incorporating mothers, their young, grown daughters and their offspring. Herd size may range between two and twenty four , but typically 9 – 11. However these figures may not be accurate for all elephant herds. Reliable accounts have recorded elephant herds numbering up to 200 individuals and more. These unusually high numbers may be accounted for due to habitat degradation or limited resources.

The members of this family group keep together, rarely venturing 50 metres from their nearest neighbour. Activity, direction and rate of movement are all set by the matriarch, who is usually recognised as the largest cow in the herd. When the herd is disturbed, they all cluster around and turn to the matriarch for leadership. Due to the fact that leadership and experience play such a crucial role in the lives of elephant herds, the females’ lifespan extends far beyond their age of reproduction. Long term postreproductive survival is also true of man, but otherwise quite rare in the animal kingdom. When matriarchs become between 50 and 60 years old, they either leave or are abandoned by the herd, and the next oldest cow assumes leadership.

Male elephants leave the maternal herds at adolescence around 12 to 19 years. Separation is a gradual process, and the adolescent bulls may become peripheral, following the maternal herd at a distance. They don’t necessarily leave voluntarily, but are pushed out by the older females or their mothers due to an intolerance of the boisterous and sexual precociousness of pubescent males. After becoming independent, they either wander alone, or more commonly join bachelor herds. These herds typically number between 2 and 14, but may grow up to 144 individuals in some sort of temporary arrangement.

Elephant communication has been well studied, and includes tactile, olfactory, vocal and posturing communication. Their very wide array of signals and gestures include greeting, caressing, slapping, checking reproductive condition, rumbling, trumpeting, squealing, screaming and over 30 postures and movements. These cover dominance, threat, defence, submission and fighting displays of various degrees. These are all readily observed and seemingly understood by us, but recent ongoing research is exploring the elephant’s ability to communicate using ultra sound in what scientists are now calling Infrasound. These are sounds outside of our range of hearing, but are capable of travelling tens of kilometres.

Check out the macho elephant behaviour in our article “Elephant Roadblock in the Kruger Park” with an accompanying video.

Breeding

The period when bulls seek cows for mating is called the musth (pronounced must), at which time mature bulls leave their bachelor herds (should they have congregated in one) and wander alone in search of receptive cows. When bulls are in musth they are very noticeable by a combination of the following characteristics: (a) their temporal glands are functional and discharge a copious, strong smelling, watery secretion that runs down the sides of their faces (b) they may be constantly dribbling urine (c) their penis may take on a greenish tinge (d) increased aggression and (e) increased association with female herds.

Due to the fact that musth is correlated with a period of increased sexual activity and aggressiveness, an elephant bull encountered in this condition should be left well alone. Few of those elephants that come into musth will get the opportunity to mate, and therefore there will certainly be a number of very frustrated animals about, each quite capable of overturning your vehicle – keep a safe distance. Among males 25 – 35 years of age, musth may only last several days or weeks.

In older animals musth may continue for up to 5 months. During this period males often wander over great distances in search of a receptive female in oestrus. Musth may also be an accurate indicator of the health of elephants. It has been found that animals in poor condition do not come into musth and animals that become ill or are wounded while in this condition drop out of it. This is another mechanism of natural selection to ensure that only the stronger genetic material is passed on.

After the longest gestation period of any animal, some 22 months, a single calf is born. Cows give birth standing, in the midst of the herd, and the new calf may weigh 129 Kg (284 lbs.) and stand 90 cm (36 in.) at the shoulder. The calf can stand and walk within a few hours, and suckles with its mouth, not trunk from two mammae between the mother’s front legs. The calf will suckle for two years, or until its tiny protruding tusks begin to irritate its mother. The calf starts to experiment on vegetation at six months. They will basically be fully independent in ten years, the second longest period of adolescent dependency after humans.

Trunk and Tusks

There are many striking features belonging to the elephant. One is naturally the trunk. This is essentially an extended nose. This is a very powerful organ, which is highly flexible and dexterous. The tip of the trunk ends in two almost finger-like prehensile projections, capable of some very precise co-ordination. The organ is used in drinking by sucking water up it, and then squirting it into the animal’s mouth. It is also used in eating, with the prehensile tips picking food from the ground or directly from a tree and directing it into the mouth. The trunk is also obviously used for smelling.

The second striking feature is also the feature that has almost resulted in the animal’s extinction, its tusks. Although both sexes may posses them, they are far larger in the males. In the cows if they grow tusks at all, they cease growing when the cows are fully mature at 20 to 30 years. However tusk growth in males begins almost exponentially from the time they mature to the time they die. Not only do they grow longer, but they thicken substantially. Their two pillars of ivory are basically elongated upper incisor teeth that protrude from the mouth.

Ivory has been much sought after for millennia. It has been used in a multitude of ways from carved figurines to knife handles. It has been ground up for traditional medicines and manufactured as cue balls and piano keys. For these reasons the elephant has been ruthlessly hunted to the point of near extinction. The Kruger National Park’s greatest Tusker of all time was an animal called Mandleve. At his death (of old age), he was ± 56 years old, and carried 142 Kg (± 315lbs.) of ivory.

Currently the IUCN lists the animal as vulnerable, and CITES has imposed a world-wide ban on the trade of all elephant products. South Africa does not agree with this at all, as we have so many surplus elephant, however the yearly culling of between 300 and 600 animals in our largest reserve has been halted since the mid 1990′s. This reserve, the Kruger National Park, is also sitting on a stockpile of ivory valued at around 25 million rand ($3 900 000), with the stockpile growing annually. As of October 2004, this policy is under review and the culling is expected to resume in 2005.

[Source: Wildlife Campus].