Relationships within the [gorilla] group are very important. For instance, one day Puck, an adult female, and her son Cantsbee, a young blackback, were settling in to look for nest sites when it started to rain. Puck sat next to Intwali her two-year-old daughter, and Simba in a good position well out of the downpour. Cantsbee came along, staring at Simba, and moving closer and closer. Simba gave a slow pig-grunt at Cantsbee, but then Puck pig-grunted at Simba, while Cantsbee sidled even closer. Simba and Puck continued pig-grunting while Cantsbee slowly but surely pushed Simba out of the nest. He probably never would have tried to displace her if he had not known that Puck would back him up Schaller, 1989.

If this were the best of worlds, the sheer natural beauty of the animal would have sufficed as argument. But the Africans didn't even know whether they were beautiful or impressive--they'd never seen them [the gorillas]. When we did surveys in the 1970s, more than half the local population could not provide a single adjective of description. They lived in the shadow of these volcanoes and had no idea what the gorillas were like. So, they would flock to the films we showed, up to 3,000 people at a time from a village area, and the response was incredible. They saw how human this animal was. They saw a family unit; they saw a lot of maternal care--nursing, cleaning, playing, feeding; they saw paternal affection. These films did not show King Kong bursting through the bushes. Bill Weber, Assistant Director of Conservation, The New York Zoological Society.

Family Groups Primates, in general, are very social animals, and mountain gorillas are no exception. They live in small family groups consisting of varying numbers of males, females, infants, and juveniles. Each group is led by a dominant male gorilla. The dominant silverback protects his group and leads in the search for food. In most monkey populations, the females stay with their family, while the males leave their groups at adolescence. In effect, mothers, daughters, sisters, and grandmothers stay together in family groups. A different social structure emerges among gorillas--females leave their family and join other groups. Above left: This family group reached a membership of thirty-five, including four silverbacks. Photo: Courtesy of the Dian Fossey Gorilla Fund

Since gorillas are highly social animals, they try to defend one another when danger threatens. For example, poachers trying to get a baby gorilla often have to kill the dominant silverback and mother first. The death of one animal also has an effect on many others. In particular, when the dominant silverback of a family group dies or is killed by disease, accident, or poachers, the family group may be severely disrupted. The large family group may split into two or more smaller groups. When a new silverback takes control of a family group, he may kill all of the infants of the dead silverback. This practice of infanticide is seen in various monkeys, prairie dogs, and lions (to name a few animals). It is an effective reproductive strategy in that the new male conceives progeny that perpetuate his genes. In stable peaceful groups, there is no apparent evidence of infanticide. Photo: Courtesy of the Dian Fossey Gorilla Fund

Gorillas' Communication Gorillas are active in communicating with each other by both sounds and body language. Many of their actions reflect the hierarchy or pecking order of the group. Here a silverback makes a "threat gesture" by turning sideways to show his size and "yawning" to exhibit his large canine teeth.

Gorillas are known to make over twenty-five distinct sounds. Some of these areas follows:

• Hooting, vegetation slapping, and chest-beating, often accompanied by strutting. This is done by rival males.
• Sharp grunting: a sign of disapproval.
• Chuckling: a sign of playfulness.
• Screaming: a sign of alarm or warning.
• High-pitched barking: a sign of curiosity.
• Roaring: a sign of aggression.
• Belching: a sign of contentment.
  

Gorillas also love to play. Here, two gorillas play their favorite game, 'gotcha'! Photos: Courtesy of the Dian Fossey Gorilla Fund

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