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Gorillas - their Home
Like all other apes, all gorillas live in the rain forest. Only chimpanzees also occur in the tree Savannah.
The gorillas roam through their home ranges from one feeding place to the next. They feed almost exclusively on plants, which they eat in large quantities. To be able to process these masses of plant material, the gorillas have very strong chewing muscles. Their teeth are very much like human teeth, except for the very long, pointed canines of adult gorilla males. The males don't use those for feeding but for fighting against competing males.
Gorillas - Life in a family
Gorillas live in groups. As a rule, the groups consist of one adult male, several females and their offspring. One way such a harem group starts is by a female transferring from her natal group to a lone male. Growing offspring of either sex usually leave their natal group. Females always join another group or a lone male, whereas male gorillas usually turn into loners.
In males, the separation process is slow: they spend more and more time on the edge of the group until they leave altogether. In contrast, a female leaves her group only if she encounters another male. The home ranges of various gorilla groups and of lone silverback males overlap, so encounters are frequent. Lone males often make a special effort to seek out harem groups out, as this is their only chance to gain females. The leaders of stable harem groups avoid contact with other adult males in order to avoid losing females. If they detect a competitor, they try to drive him away by displaying or attacking.
Gorillas - Rank Order
In a group of gorillas there is a clear hierarchy. The leading silverback has the highest rank, and adult females are dominant over young animals. Among the females, rank depends on factors such as how long they have been in the group, for example. Among the young animals, rank usually depends on age.
A gorilla male achieves his high-ranking position not only because of his strength, which he proves when fighting against competitors, but also because of his experience and abilities. For instance, he has to know the area very well in order to lead his group to the right feeding sites at the right time of the year. These days, it is also very important that he knows how to deal with humans. Experienced gorilla males can, for example, remove poachers' snares from the hands or feet of their group members. As young males lack the necessary experience, they will find it difficult to lead a group: If the females notice that their silverback male is too inexperienced, they will transfer to another one.
Gorillas - Threats
- stress caused by the constant presence of people,
- diseases transferred by people or domestic animals,
- hunting for their meat,
- hunting for fetishes and trophies,
- hunting in revenge for crop-raiding,
- injuries through snares set for other animals,
- war,
- isolation of gorilla populations in small forest islands,
- destruction of the forest through deforestation, fire or mining of mineral resources.
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