National Geographic : 1970 Jan
National Geographic, January 1970 to be taken out into the surrounding forest. These excursions provided a unique oppor tunity for observing feeding habits, grooming, and vocalizations at close range in their natu ral habitat (pages 60-61 and 64-5). It was fas cinating to watch the intricate maneuverings of the animals as they searched for worms and beetles in tree trunks or groomed them selves for minute flecks of dead skin. Then, all too soon, the infants were de manded for their trip to the zoo. Their last excursion into the forest was a maudlin one on my part, but happily the babies did not know they would never see their mountain home again. Silverback Rules Each Forest Group Two days after Coco and Pucker had left, I resumed my field work. But after more than a two-month absence from my wild gorilla groups, I was uncertain of my reception. Thus far in my studies I had watched nine groups, each numbering from 5 to 19 mem bers. The average was 13. Of these nine, I had chosen four for close-up observation. One dominant male, or silverback (so called because the hair across the male goril la's back turns silver with age), reigns without question within each group. The subordinate males serve as sentries and guards. For clarity in my field notes, I refer to the groups by numbers. The gorillas I contacted on my first day back in the field were Group 8; they are headed by Rafiki, a wise old silver back (page 53). Armed with some new vocalizations learned from Coco and Pucker, I approached the group, feeling like a stranger. Would I have to win their acceptance all over again? "Naoom, naoom, naoom," I croaked, first in the deep tones of Coco, then in the higher pitched voice of Pucker. (This particular sound, I had learned, apparently meant, "Food is served. Come and get it!") The reac tion was something to behold. Rafiki came up to me with an expression that seemed to say, "Come on, now. You can't fool me!" They had not forgotten me. Rafiki's particular group is unique in that there are no females or infants. Since the five males have no young to protect, they give full rein to their curiosity. It would seem that the boredom of their bachelor life is relieved by the many contacts we have shared. These contacts have been very exciting ones. Sometimes I observe the group from a tree, and Peanuts, Geezer, and Samson, the three youngest males, climb up to join me. It is they who investigate my camera equipment and my boots and clothing. Rafiki and his friends were not a bachelor group when I first met them almost two years earlier. Living with them then was an elderly, doddering female with atrophied arms, dried up breasts, and graying head; I estimated her age at about 50 years. If it isn't being too anthropomorphical, the five males seemed to love her, and most group activities centered about this aged matriarch. I named her Koko. Mutual grooming-a kind of social ape behavior involving meticulous hair parting, searching, and plucking of particles-could always be induced by Koko. When she started it, the others would follow suit, and within a few minutes there would be an entire chain of intently grooming gorillas-a most unusual occupation among these particular apes. Since Koko's death some twenty-three months ago, I've noted mutual grooming within this group on only two occasions. Koko's Final Trip Poses a Mystery Not long before she disappeared, Koko showed signs of actual senility by wandering away in aimless circlings. On such occasions the five males would just sit down and wait for her return. Sometimes Rafiki would give a soft hoot-bark, causing Koko to head back toward him. She would then go up to Rafiki and embrace him in a most human-appearing way; invariably he would return the embrace. Gorillas build sleeping nests-usually on the ground-of foliage, branches, and some times moss or loose soil. Frequently Koko and Rafiki would share the same nest, and looked for all the world like a gracefully reclining old married couple who need no words to strengthen their mutual respect. Then, for two days, Koko and Rafiki were absent from the group, leaving the remaining The woman who came to dinner: Crouched in a ravine, Miss Fossey picks leaves to chew, a gesture of reassurance for a curious blackback. Her gloves protect against nettles. Partial con cealment heightens gorillas' interest, the author discovered. She avoids standing, since that might cause uneasiness in the animal, who leans on callused knuckles in the stance gorillas favor. EKTACHROME BYALANROOT© N.G.S.