Geoscience Reference
In-Depth Information
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An Unexpected Hero
The Gambian pouched rat is the largest murid
rodent in the world. This nocturnal rodent
can grow as large as a raccoon. They are often
hunted for food. Gambian rats have the poten-
tial to save lives. Gambian rats are being trained
to recognize explosives (through smell) and
detect land mines in Africa. The rat is condi-
tioned to associate the smell of TNT with a
reward of food, training the rat to seek out the
explosive. These rats are well suited for the job.
They are adapted to the hot African climate and
have an excellent sense of smell. Gambian
pouched rats are smaller and lighter than dogs
(typically used in the detection process), which
severely decreases their chance of triggering
the mine. Gambian rats are much cheaper to
obtain and train than their canine companions.
Once the rat has discovered the buried mine, it
will scratch at the soil, and the mine will be iden-
tified and destroyed.
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found in the seasonal forests. Pouched rats and
mice, like the Gambian rat, are native to Africa
and live in seasonal and scrub forests. Pouched
rats can carry large quantities of food that they
store and use to survive in the dry season when
food is scarce.
Tree hyraxes are medium-size rodent-like ani-
mals with small ears, short legs, and no tails. They
are found in the trees of the forest. Rock hyraxes
are found in the drier scrubland areas where rocky
outcrops are present (see Figure 5.15).
Primates are abundant in the seasonal forest,
although not as diverse as those in the rainforest.
Mona monkeys, vervets, and several species of
colobus monkeys are seen in the trees, while man-
drills and baboons are found searching for food in
trees or on the ground. Chimpanzees are the only
member of the great ape family present in the sea-
sonal forests of Africa. Chimpanzees are primar-
ily frugivores, but also consume seeds, nuts,
flowers, leaves, pith, honey, insects, eggs, and ver-
tebrates, including monkeys.
Many species of lemurs are found in Madagas-
car and nowhere else. Lemurs through adaptive
radiation have evolved to fill niches taken by squirrels, rats, and monkeys, as well
as some birds. Although many species have become extinct, eight species live in
the dry forests of western Madagascar, including the mongoose lemur, golden-
crowned sifaka, Perrier's sifaka, Milne-Edwards's sportive lemur, brown lemur,
and three species of mouse lemurs.
African seasonal forests have a large number of ground-dwelling mammals,
including those found in savannas and woodlands. The largest of these mammals
is the African elephant, who finds shelter in the dry forests and a seasonal bounty
of fruits (see Figure 5.16). Many other large African herbivores are present in the
seasonal forest as permanent residents or migrants from nearby rainforests or sav-
annas. These include zebra, bongos, roan antelope, sable antelope, greater kudu,
common eland, wildebeest, blue and yellow backed duikers, impalas, buffalo, for-
est hogs, and bush pigs. The black rhinoceros is found in some Zambezian wood-
lands but is locally extinct in other areas.
Carnivores in the forest include hyenas, mongooses, civets and genets, African
wild dogs, smaller cats, leopards, cheetahs, and lions. These are the main predators
in the forest. Hyenas are more common in savannas, but spotted and striped hye-
nas also have been found in dry forests and scrublands. Genets, civets, and
