Early in my research, which the National Geographic Society has supported throughout, I discovered that these powerful but shy and gentle animals accepted and responded to my attentions when I acted like a gorilla. So I learned to scratch and groom and beat my chest. I imitated my subjects' vocalizations (hoots, grunts, and belches), munched the foliage they ate, kept low to the ground and deliberate in movement—in short, showed that my curiosity about them matched theirs toward me.
The returns, in new knowledge of gorilla behavior, have exceeded my expectations. I've learned what intelligent and sociable animals these are. Fathers pluck infants from their mothers to groom them, and once I saw an old male tickle a youngster with a long-stemmed flower.
On the negative side, I have had to bury gorilla friends killed and dismembered by poachers, and I've seen how man's encroachment threatens the very survival of Gorilla gorilla beringei, already declared a rare subspecies and existing today only in the Virunga Mountains.
Over the years familial units in my study area, where a succession of students have assisted me as field observers, evolved toward different fates. Nunkie formed an influential new group, one of three dozen we have observed, identified simply by number, and studied. Group 4, under maturing Uncle Bert, suffered decimation that virtually wiped it out. Group 5, led by aged and experienced Beethoven, matched losses with gains and held together as a prime example of group stabilization.
At the outset it is important to know that establishing the genealogy—the family tree, if you will—of each gorilla group was crucial to my study. Transfers between groups, births and deaths, switches in pecking order—these events of population dynamics constantly altered group composition. Understanding the reasons for this fluidity in dramatis personae has been a major goal; however, the shuffling of names and numbers may complicate the picture.