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The African Savanna Elephant is the largest land mammal with
adult males achieving body weights greater than 7 tonnes.
Parker (1979), from a detailed study of ivory, showed a western
race of savanna elephants extending through Angola and northern
Namibia across as far west as Matabeleland in Zimbabwe. Namibia
is famous for its "Desert Elephant" and, although it has now
been demonstrated that these desert-dwelling animals are part
of a continuous population extending to Etosha National Park,
they possess adaptations not seen in other savanna elephants
- large body size being one characteristic. The largest elephant
recorded (from Fenykoevi in Angola in 1955) was 4 metres high
and is probably from the same race as Namibia's north-western
elephant.
The elephant is described as a 'Pachyderm' because of its
very thick skin which may reach a thickness of 3-4cm. Although
both species of African elephant have five well-formed digits
on both fore and hind feet, Loxodonta africana displays 4
nails on the fore feet and 3 on the hind, whereas L. cyclotis
has 5 and 4 respectively.
The name Loxodonta is derived from the lozenge-shaped teeth
of the genus. During its lifetime a progression of six molars
erupt from the posterior of the jaw and move along the mandibles,
wearing out as they go, until they fall out. The succession
of molars has allowed fairly accurate ageing of animals (Laws
1966, Sikes 1966, 1968).
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Figure 4 Relationship between age and tusk size adapted
from Pilgrim & Western (1986)
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The tusks are elongated upper incisors consisting of a unique
mixture of dentine and calcium salts which exhibits a diamond
pattern in section. Elephant tusks grow throughout their lifetime
(Figure 4). The largest tusks on record are from Kenya and
weighed 102.3 and 97kg. In the southern African region the
largest recorded pair are 64.3 and 64.8 kg from the Limpopo
Valley (Best & Best 1977). Namibian ivory (from the western
population) has a reputation for being hard and brittle and
broken tusks are a common feature of large adult males.
Both males and females possess glands on the temporal region
of the face which secrete copiously irrespective of age, sex
or season (Short 1972). The discovery of 'musth' in African
elephant is relatively recent (Moss 2000) and this discharge
is one of the symptoms displayed by adult males in a musth
condition. Musth is directly linked to reproductive behaviour
and occurs in males over 29 years of age mainly during the
rains and lasts for two-three months at a time.
Elephants are capable of communications over long distances
using infrasound inaudible to the human ear (14-20Hz). Much
of the communication is linked to females in oestrus but also
plays a rôle in relaying alarm messages and maintaining contact
when elephant groups are separated (Payne 1998, Charif et
al 2004).
Ansell (1974) recognised four subspecies of savanna elephant
but included the Kaokoveld elephant in the main type L.a.
africana.
| |
male |
female |
| Largest: Fenykoevi - Angola 1955 |
400 |
- |
| Namibia: from Lindeque (1991) |
>350 |
>300 |
| Namibia: Best & Best (1977) |
up to 350 |
- |
| Zimbabwe: Martin (1987) |
up to 340 |
250 |
| Africa: Macdonald (2001) |
330 |
270 |
| Southern Africa: Shortridge (1934)
|
305-320 |
- |
| Asia (Elephas) Macdonald (2001) |
250-300 |
- |
| Forest elephant: Smithers (1983) |
235 |
210 |
| Table 1: Shoulder heights for elephant |
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Martin (2005) took the body length and age data for Etosha
from Lindeque (1991) and applied the formula from Chase (et
al 2003) to derive shoulder heights for these elephants. Lindeque's
data only extends up to age classes of 30 years but, in these
classes, the indications are that both males and females are
at least 10% taller than the Kruger National Park elephants.
Applying this ratio to the oldest animals in the population
suggests that shoulder heights over 3.5 metres would be expected.
Sexing of adult elephants
Field experts and authors of books on African elephants will
advise that male elephants are taller than females; that they
have thicker tusks; that the foreheads of adult females are
pointed whereas those of males are sloping; that the back
and belly of a male elephant slopes downwards towards the
hind legs whereas in the profile of a female these features
are more horizontal; and that the shape of the prepuce in
the adult male forms an abrupt right angle with the belly
whereas the vulva of a female has a triangular profile (Figure
5).

Figure 5: Identification of adult male and female
elephants
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The presence of mammary glands is limited to females only.
Although males have vestigial nipples, they lack the pronounced
swelling between the forelegs. The mammary glands can be detected
in all views of a female elephant (except perhaps from dead
astern). The belly of an adult female dips downwards immediately
behind the forelegs and the skin of the mammary gland is paler
than the belly skin.
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