Geoscience Reference
In-Depth Information
information (DNA). Although hunting bonobos is illegal, poaching continues to
have a dramatic effect on their populations. Numbers of bonobos have drastically
fallen, from an estimated 100,000 in 1984 to about 5,000 today. If drastic measures
are not taken, this species will soon disappear.
Many species of lemurs live in Madagascar. Lemurs are found nowhere else.
Through adaptive radiation, they have filled niches taken by squirrels, monkeys,
and sloths, as well as some birds in other forests. Current thought is that Madagas-
car's lemurs descended from a single species that arrived on the island 65-60 mya.
Although many have gone extinct, five families, 14 genera, and 32 species survive
on Madagascar. In the rainforest, small nocturnal nest-building lemurs, such as
mouse lemurs; medium-size diurnal leaf- and fruit-eating lemurs, such as the ring-
tailed lemur; small, nocturnal, arboreal, leaf-eating sportive lemurs; and the larger
insectivorous aye ayes can still be found. Like other primates, lemurs play a crucial
role in the dispersal and germination of certain rainforest plants.
The majority of large African herbivores belong to the order Artiodactyla, and
many of these even-toed ungulates inhabit the rainforest, including okapis, bongos,
antelopes, forest buffalo, hippos, forest hogs, and bush pigs.
The okapi is a relative of the giraffe adapted to life in the forest. Okapis look
like a cross among antelopes, giraffes, and zebras. They have dark brown or gray
coats that help them blend into the dark forests. The okapi's legs have white stripes
patterned like a zebra (see Plate X). Okapis feed on shoots of young shrubs. They
are solitary animals standing about 5 ft (1.5 m) at shoulder height, and weighing
between 450-650 lbs (200-300 kg). Okapis tend to be secretive and occur only in
small parts of the rainforest in the DRC.
Several antelopes inhabit the rainforest, including bongos, royal antelopes, and
duikers. The bongo is a large antelope reddish-brown in color with white stripes
across the back. Bongos have horns that project backward so as not to get caught in
the dense foliage of the forest. They use their horns to uproot young trees to feed
on the roots. Like okapis, bongos are solitary creatures that can move agilely
through the forest unnoticed.
Duikers are small antelopes. Duikers, which means ''diving buck,'' are named
for their ability to dart off through the forest and hide in thick brush. Fifteen species
live in the tropical rainforests of Africa. Some are widely distributed through the
forest, while others are limited in distribution. The Jentink's duiker and zebra
duiker are restricted to the remaining rainforest of Liberia and the western C
ote
d'Ivoire. Duikers have rounded backs and short necks with the head held close to
the body. They do not have horns. Their coats vary in color from brown to yellow-
brown to reddish. Many are named for their coloration, for example, the red-,
gray-, and yellow-backed duikers. They tend to weigh about 145 lbs (65 kg) and
stand no taller than 1.5 ft (45 cm). Duikers prefer to browse on shoots and leaves,
but some will also eat termites and small birds.
While the more common Nile hippopotamus makes its home primarily in the
water, another hippo lives mainly in the forest. The pygmy hippopotamus is much
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