The Behavioral Ecology of Efe Pygmy Men in the Ituri Forest, Zaire 9780915703241, 9781949098860, 0915703246

Table of contents :
Contents
List of figures
List of tables
List of plates
Foreword, by John Speth
Preface
Chapter 1: Introduction
Theory and Choice of Variables
The Influence of Previous Studies of Pygmies
Chapter 2: The Study Area and Its Inhabitants
The Physical Environment
The Effects of Human Occupation
Peoples Inhabiting the Ituri Forest
The Study Area Study Populations
Sample Populations
The Lese Dese
The Efe
The Annual Cycle
The Efe Annual Cycle
Chapter 3: Methods
Observations of Behavior
Choice of Observation Technique
Sampling Schedules
Recording Methods
All-Day Observations of Behavior
Observer Effect
The Problem of Independence
Ad Lib Observations
Observations of Hunts
Other Data Collection
Demography
Anthropometry
Food Procurement and Exchange
Questionnaires
Event Calendars
Quid Pro Quo
Data Analyses
Chapter 4: Activity Patterns and Food Acquisition
Subsistence and Maintenance Activities
Hunting
Food Gathering
Honey Gathering
Collecting Firewood and Water
Food Preparation
Camp Maintenance
Manufacture and Maintenance of Implements
Village-Related Work
Travel Between Camp and Village
Moving Camp
Total Subsistence-Related Work
Child Care
Self Care
Leisure
Recreation
Smoking
Locomotion
Distance Traveled
Comparisons with Non-human Primates
The Effect of Age on Distance Traveled
Health and Illness and Activity
The Kinds of Illness
Health and Activity
The Effects of Weather on Activity
Camp Location
Distance from the Village
Seasonal Location of Camps
Activity Patterns: Forest vs. Village
Hunting and Gathering
Work in the Village
Total Subsistence Work
Food Acquisition
Summary
Conclusion
Chapter 5: The Sociology of Efe Hunting
Hunting Methods and Prey Species
Monkey Hunts
Ambush Hunts
Group Hunts
Time Allocation During Hunts
Locomotor Patterns
Distance Traveled
Hunting Returns
Monkey Hunts
Ambush Hunts
Group Hunts
Group Hunts: Sharing
The Effect of Sharing on Individual Procurement Success
Age and Procurement Success
Limited Needs for Meat
Comparison of Hunting Returns: All Methods
The Advantages of Group Hunting
Summary
Chapter 6: Hunting Success and Marriage
Marriage Patterns of Efe and Lese
Efe Male Strategies of Competition
Overall Hunting Success
Marital Success and Hunting Success
Wealth, Hunting and Marriage
Chapter 7: Conclusion
The Pygmy-Villager Relationship
Sex Differences in Behavior
References Cited
Appendix 1: Questionnaire
Appendix 2: Checksheet
Appendix 3: Glossary of Codes and Definitions
Plates

Citation preview

Anthropological Papers Museum of Anthropology, University of Michigan No. 86

The Behavioral Ecology of Efe Pygmy Men in the Ituri Forest, Zaire

by Robert C. Bailey

with a foreword by John D. Speth

Ann Arbor, Michigan 1991

© 1991 by the Regents of the University of Michigan The Museum of Anthropology All rights reserved Printed in the United States of America ISBN 978-0-915703-24-1 (paper) ISBN 978-1-949098-86-0 (ebook) Cover design by Marty Somberg Library of Congress Cataloging-in-Publication Data Bailey, Robert Converse. The behavioral ecology of Efe pygmy men in the lturi Forest, Zaire / by Robert C. Bailey ; with a foreword by John D. Speth. p. cm. - (Anthropological papers/ Museum of Anthropology, University of Michigan) ; no. 86) Revised version of author's doctoral dissertation which was completed in 1985. Includes bibliographical references. ISBN 0-915703-24-6 (pbk. : alk. paper) 1. Efe (African people}--Hunting. 2. Efe (African people}--Agriculture. 3. Lese (African people}--Hunting. 4. Lese (African people}--Agriculture. 5. Hunting and gathering societies-Zaire--Ituri Forest. 6. Subsistence economy-Zaire--Ituri Forest. 7. Forest ecology-Zaire--lturi Forest. 8. Shifting cultivation-Zaire--lturi Forest. 9. Human behavior. I. Title. II. Series: Anthropological papers (University of Michigan. Museum of Anthropology); no. 86. GN2. MS no. 86 [DT6SO.E34] 306 s-dc20 91-10954 (306'.096751] CIP The paper used in this publication meets the requirements of the ANSI Standard 239.48-1984 (Permanence of Paper)

Contents

List of figures List of tables List of plates Foreword, by John Speth Preface

VL VL VLL LX XLLL

1 INTRODUCTION Theory and Choice of Variables The Influence of Previous Studies of Pygmies

CHAPTER

CHAPTER

2

THE STUDY AREA AND

ITs

INHABITANTS

The Physical Environment The Effects of Human Occupation Peoples Inhabiting the Ituri Forest The Study Area Study Populations Sample Populations The Lese Dese The Efe The Annual Cycle The Efe Annual Cycle CHAPTER

3

METHODS

Observations of Behavior Choice of Observation Technique Sampling Schedules Recording Methods All-Day Observations of Behavior Observer Effect The Problem of Independence Ad Lib Observations Observations of Hunts Other Data Collection Demography UL

1 3 5

9 9 10

12 14 15 16 19 20 21

25 25 25

26 28

29 30 31

32 32 33 33

Anthropometry Food Procurement and Exchange Questionnaires Event Calendars Quid Pro Quo Data Analyses CHAPTER

4

ACTIVITY PATTERNS AND FOOD ACQUISITION

Subsistence and Maintenance Activities Hunting Food Gathering Honey Gathering Collecting Firewood and Water Food Preparation Camp Maintenance Manufacture and Maintenance of Implements Village-Related Work Travel Between Camp and Village Moving Camp Total Subsistence-Related Work Child Care Self Care Leisure Recreation Smoking Locomotion Distance Traveled Comparisons with Non-human Primates The Effect of Age on Distance Traveled Health and Illness and Activity The Kinds of Illness Health and Activity The Effects of Weather on Activity Camp Location Distance from the Village Seasonal Location of Camps Activity Patterns: Forest vs. Village Hunting and Gathering Work in the Village Total Subsistence Work Food Acquisition Summary Conclusion tv

35 36 37 37 37 39

41 42 42 44 45 47 48 48 49 50 51 52 52 53 55 55 55 56 57 57

59 59 60 60 62 64

65 66 66 67 68 68 68 70 73 74

CHAPTER

5

THE SOCIOECOLOGY OF EFE HUNTING

Hunting Methods and Prey Species Monkey Hunts Ambush Hunts Group Hunts Time Allocation During Hunts Locomotor Patterns Distance Traveled Hunting Returns Monkey Hunts Ambush Hunts Group Hunts Group Hunts: Sharing The Effect of Sharing on Individual Procurement Success Age and Procurement Success Limited Needs for Meat Comparison of Hunting Returns: All Methods The Advantages of Group Hunting Summary CHAPTER

6

7

ApPENDIX

1: 2: 3:

97 98 101

121

REFERENCES CITED

ApPENDIX

90 93 94

111 112 114

CONCLUSION

The Pygmy-Villager Relationship Sex Differences in Behavior

ApPENDIX

81 83 83 84 84 84 85 86 90

103 104 105 106 107 108

HUNTING SUCCESS AND MARRIAGE

Marriage Patterns of Efe and Lese Efe Male Strategies of Competition Overall Hunting Success Marital Success and Hunting Success Wealth, Hunting and Marriage CHAPTER

77 79 79 80

QUESTIONNAIRE CHECKSHEET GLOSSARY OF CODES AND DEFINITIONS

135 136 137

beginning on page 145

PLATES

v

List of Figures 2.1 5.1 5.2 5.3 5.4 5.5 6.1 7.1

Map of the Ituri Forest region, 10 Frequency distribution of group hunts by number of hunters, 87 Mean hunting returns, 88 Meat returns for group hunts, 91 Meat procurement efficiency against mean time, 96 Length of hunts by number of hunters, 97 Procurement success and material wealth, 109 Fitness as a function of time, 117

List of Tables 3.1 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 4.10 4.11 5.1 5.2 5.3 5.4 5.5 6.1 6.2

Number of observations, 27 Time allocation of Efe men, 43 Time devoted to subsistence and maintenance, 53 Smoking and material wealth, 58 Illnesses recorded, 61 Expected and observed time allocations of sick vs. non-sick, 63 Rain data, 65 Observation frequency related to camp location, 67 Mean distance of camp from village, 67 Time allocation as a function of distance from village, 69 Caloric contribution to Efe diet, by gender, 71 Caloric contribution of cultivated and foraged food, by gender, 71 Returns of 46 monkey hunts, 85 Returns of 45 ambush hunts, 86 Partial summary of 71 group hunts, 89 Ranking of hunters before and after distribution, 92 Summary of all hunting returns, 98 Marriage patterns of Efe and Lese, 106 Overall hunting success, 107

Vl

Plates

(beginning on page 145) 1. 2. 3. 4. S. 6. 7. 8. 9.

An Efe camp. Two young men. Man making poison-tipped arrows. Butchering a duiker. Butchering an elephant. Harvesting honey. Efe and Lese women processing peanuts. Efe woman moving camp. Lese and Efe girls in ima celebration.

vu

Foreword

John D. Speth University of Michigan

I think it is fair to say that the Man the Hunter symposium was one of the most significant landmarks in the study of hunters and gatherers, one that quickly captured the imagination of the entire anthropological discipline. Almost overnight the long-standing, rigid, patrilineal-patrilocal model of band societies was swept away and replaced by a new one which emphasized their fluidity, flexibility, and ecological adaptedness. Perhaps more than anything else, it was the quantitative "input-output" analysis and time-allocation data gathered by Richard Lee among the !Kung San, or Bushmen of the Kalahari desert, elegantly molded into a portrait of "original affluence" by the literary eloquence of Marshall Sahlins, that transformed the prevailing view of foragers from one of marginal "hangers-on," struggling to survive in the world's most inhospitable environments, into one of resilient, healthy, and highly successful societies, living in ecological harmony with their surroundings, perhaps not unlike their forebears who dominated the globe for countless millennia prior to the advent of food production. The decade following the Man the Hunter symposium was one in which anthropologists came to see the world's foragers largely through Bushman eyes. The San, and particularly the !Kung, became the standard-the quintessential foragers-upon which new models were built and against which older ones were evaluated. The tremendous influence of the Kalahari Project is hardly surprising, as the San at that time provided the only hard, quantitative data on what hunters and gatherers actually did for a living. Every freshman anthropology student learned about the !Kung, that their diet was energetically and nutritionally adequate, despite their harsh desert environment, that hunting and gathering societies should more properly be called gathering and hunting LX

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Behavioral Ecology of Efe Pygmy Men

societies, since plant foods, not meat, overwhelmingly predominated in their diet, that their daily work schedule was unexpectedly light and leisurely, leaving them far more time for socializing and other activities than one found among supposedly "more advanced" farming societies, and that they had remarkably low levels of fertility without the aid of contraceptives, which somehow managed to keep their populations marvelously in balance with their resources. The Man the Hunter symposium conveyed a real sense of excitement that we had at last begun to understand what foraging societies were all about and how they worked. At the same time, however, the paucity of quantitative data from foraging groups other than the !Kung hindered rigorous comparisons, and underscored the urgent need for fieldwork among band societies in other environments before they had all vanished. In response to this sense of urgency, the 1970s and 1980s witnessed the birth of an entire new generation of long-term, often interdisciplinary field studies, providing us with a wealth of new information and insight into the nature of these fascinating societies. Scholars from all four of anthropology's traditional subfields-ethnology, archaeology, biological anthropology, and linguistics-armed with a diverse array of intellectual and theoretical perspectives-e. g., symbolic, cognitive, Marxist, ecological-have actively participated in this upsurge in research. The result has been a veritable explosion in the literature on hunters and gatherers, and perhaps not unexpectedly a growing recognition that not all foragers are like the Bushmen. To the contrary, one of the most striking contributions of forager research in the post-Man the Hunter era has been the demonstration of just how variable these societies can be in virtually any dimension one chooses to look at. Thus, some foragers in tropical and subtropical latitudes consume far more meat than the !Kung, some have higher fertility levels and shorter birth intervals, many work harder, some are taller, others not as lean, and so forth. The field is maturing and in the process the focus of research has shifted from an emphasis on producing "normative portraits" of band societies to the search for the nature and underlying causes of this variability. One of the most exciting of these new long-term research efforts-the Ituri Forest Project-was launched by Robert Bailey more than a decade ago among the Efe Pygmies in the northern Ituri Forest of Zaire. Since the inception of the project, Bailey and his associates have maintained an almost continuous presence among the Efe (and among nearby Lese horticultural communities), conducting research on a broad spectrum of anthropological, demographic, biophysical, and medical issues. This project has vastly improved our knowledge of these fascinating hunters and gatherers, providing detailed quantitative data on their diet, health,

Foreword

XL

social, political and economic organization, and the degree to which their livelihood is influenced by, and ultimately dependent upon, their close ties with farmers. One of the most important studies to emerge thus far from the Ituri Project is Robert Bailey's own detailed look at the behavioral ecology of Pygmy men, an in-depth analysis of the range of activities in which men participate, differences among these men in the way each allocates time to these activities, and the differential costs and payoffs that accrue from their individual choices. Some readers may immediately become apprehensive at encountering a work that labels itself "behavioral ecology," fearing that such an approach of necessity holds that human behavior is genetically programmed. As Bailey himself is quick to point out, however, behavioral ecology in no way assumes or implies any sort of genetic determinism. Quite the contrary, behavioral ecology simply shifts the focus from organizations or institutions to individuals, and employs models that hold health, survival, and reproductive fitness as useful ways of assessing the degree to which particular individual choices and behaviors are successful or beneficial. As the reader will quickly discover, the kinds of insights that emerge from Bailey's study actually complement and dovetail beautifully with those from other intellectual traditions in anthropology. Clearly, what is ultimately needed is not a vote to decide which approach is the right one, but a means for integrating the insights from these differing perspectives into a single coherent framework. In this volume Bailey explores in detail what a focal sample of 16 Pygmy men in two different bands did with their time. He looks in depth at their hunting activities, documenting the amount of time each individual spent in the chase, the techniques each chose, variability in the number of individuals that hunted together, and the payoffs of these different options and strategies. He then looks at the way meat was shared among individuals, and the extent to which the share each received corresponded with his success as a hunter, his age, marital status, or wealth as measured by the number of his material possessions. Bailey also addresses the fascinating issue of "hypergyny," the upward marriage of Pygmy women to wealthy farmer men. His data show that hypergamous marriages significantly reduce the number of potential mates available to Pygmy men, forcing them to devote more time to hunting and other forest activities in order to compete more effectively for marriage partners. These and many other issues are explored with great clarity and perceptiveness by Bailey in this interesting and important contribution. The Museum of Anthropology of the University of Michigan takes great pride in publishing this volume, a substantially revised and expanded

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Behavioral Ecology of Efe Pygmy Men

version of his doctoral dissertation, making it widely available for the first time to the anthropological community. Bailey's study sheds important new light on one of the world's most fascinating and least known hunter-gatherer groups-the Ituri Forest Pygmies-and it will no doubt provide an invaluable resource for comparative studies, one that can be tapped by anthropologists for many years to come.

Preface

This book is a revised version of my doctoral dissertation, which was completed in 1985. It is principally about sixteen Efe Pygmy men and their families who lived in the northern Ituri Forest of northeastern Zaire. I lived and worked with them between March, 1980, and January, 1982, while conducting research for my doctoral dissertation. That research, and my subsequent work studying the biology and ecology of peoples living the Ituri Forest, was conducted as part of a long term multidisciplinary project, called the Ituri Project. The Efe are semi-nomadic, bow-and-arrow hunting people who hunt and gather forest resources for their own consumption and for trade to village-living, slash-and-burn horticulturalists. The villagers with whom the Efe trade, work, and sometimes live are the Sudanic-speaking Lese. The Lese are variously referred to, using the Kiswahili prefix, as the Walese, or, using the Bantu prefix, as the Balese. Most Lese refer to themselves in the plural as Balese, while the official governmental designation for the tribe is Walese. For the sake of simplicity only, I refer to them as Lese throughout this book. This research has its roots in behavioral ecology and stems from my previous studies of nonhuman primates. Having studied squirrel monkeys for two years in the Colombian Amazon and anubis baboons for several weeks in southern Kenya, I was committed to a career in the study of primate behavior and ecology. My goal was to understand the evolution of human behavior by making inferences from the behavioral ecology of our closest living relatives, nonhuman primates. In 1976 in southeastern Cameroon, having been previously overwhelmed by the broad diversity of peoples living in east and central Africa, I decided to xu£

XLV

Behavioral Ecology of Efe Pygmy Men

take a more direct approach to the study of our own species. Why not study humans to try to understand the evolution of human behavior? If we could discover the factors that contributed to the variation in subsistence patterns and social organization that I had seen in Africa and the Amazon, we might ultimately derive principles that could allow us to infer processes at work for generations in the past. I became excited about applying some of the models and methods that I had learned as a primatologist to the study of the behavioral ecology of people. Coincidentally, at the time of this contemplated shift from nonhuman primates to humans, I was observing talapoin monkeys in the Dja Reserve in southeastern Cameroon with two families of Biaka Pygmies. Deep in the forest, far from any village or source of cultivated foods, the Biaka guided me and fed me foraged foods for ten days. Because they seemed so well integrated into their forest environment with a relatively simple technology, I decided then that Pygmies in central Africa would be the best people with whom to begin my studies of human behavioral ecology. In 1978 I returned to Africa to survey eight different Pygmy populations in six countries across central Africa and to find a suitable site to establish a long-term research project. After that difficult but immensely useful expedition, I began the Ituri Project in early 1980. This book consists of seven chapters. The first is an introduction that places the research in the context of anthropology and explains why the study focuses on time allocation and subsistence. The second chapter provides background information about the physical environment, the peoples of the Ituri region, and what is known about the history of the region and its people. The methods used in my research are described in Chapter 3 to permit readers to properly assess the reliability of the quantitative information presented in subsequent chapters. Chapters 4 and 5 are the meat of the book. Chapter 4 presents the results of quantitative observations of Efe men's activities and food production, and it discusses the differences between Efe men and women in subsistence behaviors. Chapter 5 focuses on hunting by Efe men. It provides data on the efficiency of different hunting techniques and tries to answer the question, "Why do men hunt in groups?" Chapter 6 examines individual differences between Efe men with respect to hunting success and how those differences relate to marital success and wealth. The last chapter discusses results of the research in light of previous views of the relationship between central African Pygmies and village-living horticulturalists. The last chapter also extends the discussion in Chapter 4 concerning sex differences in subsistence behavior by examining men's activities in the context of behaviors that maximize biological fitness. Very few names appear in this book. I refer to people using a threedigit identification number. If this seems depersonalizing, that is the

Acknowledgments

xv

intent. While it is extremely unlikely that the lives of the Efe and Lese will be much affected by what I write here, I would prefer to err on the side of anonymity rather than risk a person's suffering as a consequence of my research. Considering the persecution suffered by many Zairois during the Simba Rebellion in the mid-1960s for having associated with Europeans, I would like to minimize the means by which anyone can trace the people with whom I lived and worked so closely. Moreover, confidentiality was, in many cases, one of the preconditions of my working with the people. Plus, there is more than one case of an anthropologist's informant becoming such a celebrity that he and his family can find no peace among the travelers and publicists that hunt him to extract his version of the ethnography. For these reasons, people appear here mostly as numbers and few place names are provided. In the few cases where I have used names, they are pseudonyms. I will gladly supply the true names of people and a key to names and identification numbers to any serious scientist requiring them for his or her research.

ACKNOWLEDGMENTS It is a pleasure to be able to acknowledge the generosity extended to me by so many people during the process of preparing for, undertaking, and reporting this work. The research was generously supported by the National Science Foundation through grants awarded to Irven DeVore. A grant to me from the National Geographic Society was instrumental in getting the Ituri Project started in 1980, and funds from the Leakey Foundation helped to support data entry and analyses. Research grants from the UCLA Academic Senate have been helpful during the revision process. The people who have helped me so much in Africa are too numerous to mention. The names of many I have forgotten, or never knew, but I shall never forget their generosity. The kindness of many missionaries in Zaire has been unfailing. I am especially grateful to the members of the Protestant missions at Nyankunde, Bunia, Lolwa, Mambasa, Akokora, and Isiro; to the Sisters and Fathers of the Catholic mission at Nduye; and to the pilots of the Mission Aviation Fellowship. Their generous assistance with transportation, communication, and medical support has been critical to the success of the project, and their hospitality and good company make fieldwork more pleasurable. I am especially grateful to the Barneses, Peg Cochran, Ruth and Richard Dix, the Etienne-Pfisters, Bill and Ella Spees, Pere Testa, and Bob Watt. Many others in Zaire offered hospitality, services, friendship, and information that facilitated our research and added to our enjoyment in the country.

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Behavioral Ecology of Efe Pygmy Men

I am grateful to them all, particularly Kurtz and Francesca von Wild, whose home has become Ngodingodi North, and Gisenya Bagire. I am grateful to the Government of Zaire for permission to conduct the research and to Dr. Kabamba Nkamany and his staff at the Nutrition Planning Center (CEPLANUT) in Kinshasa for their interest in the Ituri Project and their assistance in obtaining research clearance. I also thank Dr. Robert Franklin for bringing CEPLANUT and the Ituri Project together. Very special thanks go to the colleagues and friends with whom I shared the experience of fieldwork at Ngodingodi. I cannot imagine two better people to be in the field with than Richard Wrangham and Elizabeth Ross. I will always be grateful for their energy, good humor, intelligence, and friendship during our months together in Zaire. Richard helped to design parts of my research and he gave me many insights, some of which are imbedded in this dissertation. His creative ideas and constant enthusiasm have been truly inspiring. Without the support of Nadine Peacock I could never have undertaken nor completed this project. She helped to plan the research from the beginning; her intelligence and energy added new dimensions to the work; and her support gave me the courage and stamina to get through the most difficult periods. Working and learning together at Ngodingodi with Gilda Morelli, David Wilkie, and Steven Winn was always productive and fun. I also thank Bill Dietz, Ed Tronick, Nancy DeVore, and Barbara deZalduondo for assistance and friendship in the field. Other members of the Ituri Project deserve acknowledgement for sharing information and providing assistance, especially Peter Ellison, Jack Fisher, Helen Strickland, Hans Bode, and Mark Jenike. John Hart and Terese Hart have been informative and engaging colleagues always ready to share their refreshing ideas. Many colleagues and friends at Harvard and elsewhere provided advice, friendship, and support. Among them were: Stephen Bartz, Michael Billig, Nancy Black, Terrence Deacon, Nancy DeVore, Marjorie Ellias, Mart Fujita, Miriam Goheen, Andrew Hill, Glynn Isaac, Doona Leighton, David Marks, David Pilbeam, Anna Roosevelt, Fran Rudegeair, Thomas Rudegeair, Barbara Smuts, Charles Steele, Eric Trinkaus, John Tooby, John Watanabe, Susan Weld, and William Weld. For discussion of ideas and help with statistics, I especially thank Peter Ellison, Mark Leighton, Jim Moore, and John Noss. For invaluable help with data analyses I am very grateful to Marta Wenger, Victor Hoffman, and Robert Aunger. For her cheerfulness and accuracy during many hours of tedious data entry I am very grateful to Kristen Nygren. For helpful references and discussions during the process of revision

Acknowledgments

XVLl

I am grateful to Jared Diamond. Conversations with Kim Hill, Kristen Hawkes, Nick Blurton-Jones, Robert Boyd, Allen Johnson, Michael Raleigh, Joan Silk, Dwight Read, and Robert Aunger have also resulted in improvements. I am also indebted to Sally Horvath for her careful and expert attention to the details of editing the manuscript. Melvin Konner and John Whiting did much more than simply serve on my dissertation committee. Through example, as well as direct instruction, Mel helped me acquire the tools and the confidence to pursue human behavioral biology. John Whiting's reading of earlier drafts helped to improve the dissertation. However, his contribution goes far beyond that. I am very grateful to him and to Beatrice Whiting for their interest and support. There will never be two better role models for people starting their professional careers. To Irven DeVore I am grateful for so much. He took a chance back in 1976 and I have been reaping the rewards ever since. Thanks to his energy and vision, the facilities, funds, the human resources, and the perfect mix of sage advice and unfettered freedom were always there. Working with him closely was without doubt the greatest priveledge of my graduate career. I am grateful to my parents, Charles and Katharine Bailey who, despite certain doubt, ma.de numerous sacrifices to support my addiction for the remote and bizarre. Thanks to my brother, Charles Bailey Jr., for his constant interest, and to my sister, Katherine Bailey, who was really the one to entice me down a different path. Finally, I wish to thank the people in Zaire with whom I lived and worked. Thanks to Chief Endite Sukali and his family for their interest and enthusiastic cooperation, and to the many Lese and Efe who made the research possible. I am especially grateful to the sixteen Efe men who allowed me to shadow them for one year, and to their families for allowing me into their lives. To them I wish to express my very deepest gratitude. It would hardly be fair to acknowledge the help all these people without absolving them of all responsibility for what finally appears here. The flaws and errors are all my own and remain despite the good efforts of all those mentioned above.

1 Introduction

Each of the three principal branches of anthropology has focused considerable attention on hunting and gathering, primarily because it was the mode of existence throughout human evolution until just 10,000 years ago. Archaeologists have studied the behavior of contemporary hunter-gatherers in order to analyze how the archaeological record might have been generated by humans and their closest precursors in the distant past. They use contemporary patterns of behavior as models that are then tested in the fossil and archaeological record (Binford 1978, 1983; Gould 1978; Yellen 1977). Biological anthropologists, using the framework of natural selection theory, have attempted to discover ecological and social constraints acting on contemporary hunter-gatherers and to infer the variables that may have been working during much of human evolution (Hill 1982; Lee and DeVore 1968; Lovejoy 1981; Tanner 1981). Social anthropologists have used hunter-gatherer studies primarily to examine patterns of associations between subsistence systems, social organizations, economies, and technologies (Steward 1936, 1955; Forde 1934; Sahlins 1972; Woodburn 1980; Meillassoux 1973). The nature and goals of the research by the three major branches of anthropology have overlapped to some extent. Certainly, for example, archaeologists, biological anthropologists, and cultural ecologists alike have concerned themselves with the demographic aspects (population

1

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Behavioral Ecology of Efe Pygmy Men

densities, settlement patterns, fertility and mortality rates) of huntergatherers, and the basic principles of ecology, even if applied differently, have provided much common ground. Archaeologists, particularly, have shared with sociocultural anthropologists an interest in ethnography and with biological investigators an appreciation for the process of evolution by natural selection. Despite the convergence of these lines of inquiry into the nature and significance of contemporary hunting and gathering peoples, such studies are, as Barnard (1983:210) points out, "in a state of disequilibrium." We now find ourselves with a collection of studies mostly lacking in theory, tending to be uncoordinated, and remaining at a relatively low descriptive level (Gross 1976). A large number of studies have been conducted, yet we have been able to discern very few regularities among them; the results of the studies are simply not comparable. Yet as anthropologists we are engaged in an endeavor which, possibly more than any other discipline within the human sciences, is committed to the comparative perspective. Anthropology seeks to uncover regularities among the diversity of human biological and cultural features. It examines variation to develop generalizations, and, ultimately, its highest goal is to find general principles underlying variation in human behavIOr. In the case of hunter-gatherer studies we have so far developed numerous typologies and normative portraits of band societies (e.g., Steward 1936, 1955; Service 1962; Williams 1974; Jochim 1976; Watanabe 1978; Woodburn 1980; Testart 1981). Such typological approaches ignore or attempt to explain away diversity rather than grapple with variation and the causes of it. Instead, we should be trying to develop and test models of ecological causation and adaptive change using variation to advantage. By seeking the predictors of variation among contemporary hunter-gatherers, we may discover the prevalence of those predictors and their effects in the past (Ember 1978; Smith and Winterhalder 1981). In order to accomplish this we must design our studies to arrive at closely comparable results. As they stand, the cross-cultural data available for comparative purposes are mostly inadequate. George Murdock lamented the serious lack of agreed-upon standards among researchers in their ethnographic reporting (Murdock 1972), and others have expressed how this lack has caused cross-cultural theory to suffer (Johnson 1978). There have been advances in controlled and theoretically oriented cross-cultural research (e.g., White, Burton, and Dow 1981) that have uncovered a number of relationships between subsistence systems and socialization techniques (Whiting and Whiting 1975), fertility (Ember 1984), polygyny (Ember 1974; White, Burton, and Dow 1981), female status (Whyte 1978), and

Introduction

3

infant care (Nerlove 1974). However, lack of confidence still remains over the validity of comparing ethnographic reports that include scant explanation of methodological procedure. Theoretical advances are possible only if reliability exists (Pelto 1970; Goodenough 1970; Johnson 1978). This study is rooted in the conviction that convincing theory cannot be generated without reliable facts. In order to uncover regularities among various human societies and to discover underlying causes of variation, it is necessary to have reliable measures of significant socioecological features within the full variety of societies. To be reliable our measures must be quantitative whenever possible and collected using methods that are broadly applicable, precisely described, and repeatable. This is not to say that there is no room in anthropology for humanistic studies and traditional ethnographic description. Indeed, these and quantitative observational studies are essential complements to one another, because the former provide valuable insights into the motivations that drive the observed behaviors. However, traditional ethnographic description tends not to be good for cross-cultural comparison since there are few controls on data collection and the data are even more subject to alternative interpretations than quantitative research. Throughout, then, this study was guided by a commitment to the comparative perspective in anthropology through a conviction that human societies are amenable to quantitative research that aims to test hypotheses and measure socioecological variables of importance for cross-cultural research.

THEORY AND CHOICE OF VARIABLES Of course, the variables one chooses to measure cannot be determined in a theoretical vacuum. As Lewontin (1974:8) states: "We cannot go out and describe the world in any old way we please and then sit back and demand that an explanatory and predictive theory be built on that description." What facts we pay attention to must be dictated by our preconceptions of what variables are essential for making meaningful generalities. In choosing the variables measured in this study I was guided by both previous studies of hunting and gathering societies and by the theoretical perspective of behavioral ecology. Behavioral ecology is not a unified body of theory but rather an orientation to a suite of behavioral studies and theoretical models that have the organic processes of evolution as their underlying framework (Krebs and Davies 1984). It has drawn extensively on field studies in animal behavior and been strongly influenced by evolutionary ecology

4

Behavioral Ecology of Efe Pygmy Men

and classical ethnology. Only recently have the principles and methods of behavioral ecology been explicitly applied to the study of contemporary human societies (e.g., Bailey 1983; Bailey and Aunger 1989a; Betzig, Borgerhoff Mulder and Turke 1988; Chagnon and Irons 1979; Hawkes et al. 1985; Hill 1983; Kaplan 1983; Smith 1984; Smith and Winterhalder 1981; Turke and Betzig 1985). One very significant contribution that the perspective of behavioral ecology can bring to anthropology is an overriding emphasis on differences between individuals. Often in the past anthropologists have used the household, the village, or the society as a whole as the study unit, and they have attempted to show how a complex of behaviors creates or maintains the unit under study-often assuming a priori that the unit itself, and thus the behavior, is "adaptive." This approach, which often leads to tautologies, is in part a product of an emphasis upon viewing human social structures as the products of organizations and institutions constraining individuals. Through the perspective of behavioral ecology we view organizations and institutions as the products of the behavior of individuals managing relationships and taking a strong hand in creating the social environment about them. The approach of behavioral ecology is to recognize that the interests and abilities of individuals vary, and that those interests may be different from, or indeed in conflict with, those of other individuals and with the efficient functioning of the group or society as a whole. It also recognizes that there may be a variety of means or strategies to attain similar ends and that different strategies may have a variety of outcomes (Daly and Wilson 1983). Variation, then, becomes the focus of analysis; variation in the behavioral and physical characteristics of individuals is analyzed as a function of critical socioecological variables. The variables that are of concernthose that relate to peoples' health, survival, and reproductive successare the same that have traditionally concerned ecological anthropologists and cultural ecologists. They include such features as work effort, food production and consumption, morbidity, marital history, and fertility. These, among others, become the foci for studies because they are either direct or indirect measures of reproductive fitness. Since there has been some confusion in the past about certain aspects of behavioral ecology and the application of evolutionary theory to humans, it is prudent to make a disclaimer: ecological models and the assumptions on which they are based need not assume direct genetic causation of behavioral variation. If there is anyone feature that best characterizes the human species it is the capacity to respond to a broad range of environmental (including sociocultural) circumstances. The behavior of humans is extremely labile, capable of fine gradations and multifarious complexities. This capability arises from the use of behav-

Introduction

5

ior-generating mechanisms (e.g., our central nervous system, body physiology, etc.) that are the products of evolution by natural selection. These physical features are what give individuals the ability to respond to a great variety of complex environments and situations. It is this human capacity for making complex decisions that has a genetic basis; the specific behaviors themselves are not, nor are they assumed to be, under specific genetic control. (For more complete discussion of the genetic basis of human behavior see Ehrman and Parsons 1976; Seger 1976; Konner 1982; Plomin, DeFries and McClearn 1990.) Besides its emphasis on variation, behavioral ecology contributes to anthropology by insisting upon the scientific method. Behavioral ecology compels attention to the formulation of testable hypotheses, to the consideration of alternative hypotheses, and to careful testing procedures. Often behavioral ecology assumes some goal or maximization-as do functionalism and other theoretical perspectives in anthropology-but it makes these explicit aspects of the research. This permits the investigation of a broad diversity of specific topics which, through neo-Darwinian theory, are coherently related to each other. Ultimately, even those anthropologists who cannot accept the application of evolutionary theory to contemporary human societies will nevertheless appreciate the efficacy of an approach that provides the reliable, quantitative observational data that are indispensable for making meaningful comparisons between societies.

THE INFLUENCE OF PREVIOUS STUDIES OF PYGMIES Because Pygmies have held the fascination of Europeans since before the time of Homer, it is not surprising that there are literally hundreds of references to Pygmies in anthropological literature (see Plisnier-Ladame 1965). There have been several dozen anthropological studies of the various Pygmy populations across central Africa, but only a few have been ecologically oriented (e.g., Bahuchet 1972, 1975, 1978, 1979; Bailey and Aunger 1989b; Wilkie 1989a, b). Of the approximately twelve Pygmy populations across central Africa, there is no Pymgy population living in the forests of central Africa subsisting independently of village-living horticulturalists (Cavalli-Sforza 1986). Today, of the approximately 170,000 Pygmies distributed across the Congo (CavalliSforza 1986; Murdock 1968), none are known to live more than a few weeks without relying on agricultural food. All known Pygmy groups have close ties with at least one group of horticulturalists with whom they exchange forest products-mostly meat and honey-and labor for cultivated foods and iron implements. In most areas many groups have

6

Behavioral Ecology of Efe Pygmy Men

turned to cultivating their own crops for part of the year and many Pygmies earn some wages on plantations or logging operations. Those Pygmies who still subsist independently of market economies and their own cultivated plots, however, are all involved with villagers in a relationship that provides them with a significant amount of cultivated foods and which extends beyond economic exchange to most other aspects of their lives (Bailey 1982; Peacock 1984). Therefore, to fully understand Efe subsistence patterns and the relationship of these patterns to the social and ecological environment, the Efe cannot be considered an isolated population of forest hunter-gatherers. Virtually every aspect of Efe existence is affected by, and has effects on, Lese villager life. Therefore, the Efe and other Pygmy groups must be studied not only within the context of their ecological setting-the seasonal tropical forest-but also in the context of their close and longstanding social and economic relationships with their village-living neighbors. In order to fully understand the current socioecology of Efe groups and to come to hypotheses concerning preagricultural hunting and gathering peoples in the tropical forest, it is important to assess the Efe-Lese relationship and to identify the constraints that interactions with villagers place upon Efe subsistence patterns and social relations. Ever since the German botanist-explorer Georg Schweinfurth arrived in the Ituri region in 1870, the Pygmy-villager relationship has been the object of much attention and controversy. Schweinfurth himself saw Pygmies as "the remnants of a declining race," the original forest huntergatherers who were no longer able to subsist in the forest without the assistance of the domestic foods and iron implements of the Bantu (Schweinfurth 1874:146). The first anthropologist to work in the Ituri, Paul Schebesta, recognized that villagers derived some benefits from their association with Pygmies; however, like Schweinfurth, he felt Pygmies were so dependent upon villagers that he often referred to the Efe as "vassals" and to the villagers as their "negro overlords." To Schebesta, the Efe, whom he studied in 1930 and again in 1934, were unable to subsist without supplemental agricultural foods: " ... the pygmies have long since arrived at such a stage that they cannot depend on themselves alone for their daily needs" (Schebesta 1936: lOS). Schebesta's accounts (1936, 1937) emphasized that the dependence of the Efe on the agriculturalists extended beyond trade in iron and cultivated foods to political and ritual life as well. The anthropologist who has written the most concerning the Mbuti of the Ituri and their relationships with villagers is Colin Turnbull (Turnbull 1961, 1965a, b, 1968, 1972). Turnbull has emphasized ideological and social differences between two separate cultures; the Mbuti are

Introduction

7

primarily forest people while the Bantu are village farmers. While acknowledging exchanges of wild and domestic foods between the two cultures, Turnbull feels these were neither regular nor necessary for either side. Since the forest is capable of supplying all their needs and wants, the Mbuti are not dependent upon village products for their subsistence. The truth of the matter is simply that the village offers, for a brief while, an agreeable change of pace, an opportunity for a relaxation that is not always possible in the forest, and, one might say, better hunting, on occasion .... [T]he dependence that follows is as voluntary as it is temporary. [Tumbull196Sb:37)

It is only fair to point out that Turnbull conducted most of his research in Epulu in the central part of the Ituri among the net-hunting Mbutinot the Efe in the northern Ituri, where this study is based. He did spend an unspecified amount of time in some fifteen Efe camps (1965a:317) and agreed with Patrick Putnam (Putnam 1948:333) that the Mbuti net-hunters depend more on the forest for their subsistence, and the Efe are more dependent upon the garden produce they receive from villagers in exchange for protecting the gardens from the ravages of game animals (Turnbull 1965b:301). lohn Hart, working with Mbuti net-hunters in the southern Ituri, expressed yet a different view. He saw the relationship there as one of balanced mutual dependency whereby the Mbuti supplied villagers with protein in the form of hunted meat in return for carbohydrates in the form of agricultural produce. In Hart's view, neither side derived an advantage over the other; Mbuti and villager were locked into a mutual interdependence with neither group gaining to the detriment of the other (Hart, 1979). Faced with these conflicting views of the relationship between the BaMbuti and their village neighbors, one of the aims of this study was to quantify the degree to which the Efe rely upon the Lese villagers for their subsistence. Ideally we would like to be able to test the hypothesis that the Efe are able to subsist in the forest independently of villager food and other material goods. This is not practicable, however, since it could be done only by asking a population of Efe to live in the forest with no contact with other peoples for several generations. Whether or not Efe could survive alone in the forest today is a different issue from whether or not any population has ever existed independently of agriculture in the Ituri Forest. This latter possibility has been discussed elsewhere (Bailey and Peacock 1988; Bailey et al. 1989). If Efe could survive today purely by hunting and gathering forest resources without the use of iron implements and without supplementing their diet with

8

Behavioral Ecology of Efe Pygmy Men

domesticated food plants is a question that might be answerable using an experimental, ecological and behavioral research design. However, the fact is that today the Efe do not live such an independent life. Consequently, it was one of the objects of this study to measure the agricultural contribution to the Efe diet versus the contribution of hunted and gathered foods, and to measure what proportion of each is garnered through exchange with Lese and what proportion is acquired by the Efe directly. These were important variables to measure not only because they would finally provide quantitative information on the economic relations between a Pygmy population and their associated agriculturalists, but also they would give us per capita estimates of food intake by food type and by season. Related to the question of Efe dependence upon the presence of agriculturalists are measures of time allocation. To what extent are Efe subsistence activities directed toward agriculture and the village as opposed to hunting and gathering in the forest? Is the labor necessary to garner calories and protein from the forest more or less than to get them from the village gardens? Are some individuals better than others at subsistence tasks and, if so, what consequences might this have for other aspects of their lives? In designing behavioral observations I was guided by both a commitment to detecting differences between individuals, and a need to answer these questions concerning Efe's orientation toward the forest and the village.

2 The Study Area and Its Inhabitants

THE PHYSICAL ENVIRONMENT The Efe inhabit the !turi Forest which lies on the northeastern lip of the Zaire River Basin at an altitude between 700 and 1,000 meters. This area contains the largest number and greatest biomass of faunal species of any forested area of comparable size in Africa, and 15 percent of the species are endemic (Rahm 1966; Bigalke 1968). The Ituri is bounded in the north and northeast by open savanna, in the east by the rich highlands formed by the uplifting and vulcanization associated with the Western Rift Valley, and it is contiguous with the lowland forest to the south and west where its rivers drain into the Zaire River. The southern portions of the Ituri Forest, which extend to the equator, are gently undulating, but to the north, in the area of our studies, there are frequent outcroppings of smooth, basal granite rising several hundred feet above the forest. The climax forest vegetation of the Ituri is characterized by three dominant species of tall, hardwood legumes in the subfamily Caesalpineaceae. In the south and west, Gilbertiodendron deweverei dominates to such an extent that it can constitute 90 percent of the standing vegetation. In the area of our studies, mixed-species stands of Cynometra alexandrii and Brachystegia laurentii dominate the climax forest

9

10

Behavioral Ecology of Efe Pygmy Men

.......

·'··r'·"·;;;;)j. Y~~::-::-..:.: __ ....

"";'" Isiro j~\

fturl Project research station

".:

'·

..._....

6

roads .................. . 0°

Forest savannah ecotone / / / / / / /

---

o

Kilometers 50

Figure 2.1. The Ituri Forest region in northeast Zaire showing the location of the Ituri Project research station, Ngodingodi. The forest savanna ecotone lies just north of the study site within a day's walk.

vegetation with a number of other tall species interspersed between these codominants (e.g., Albizia zygia, Celtis mildibraedii, and Ficus spp.). The upper canopy reaches 40-50 meters in height and is discontinuous. This allows considerable light to penetrate the interior of the forest and in many places Marantaceae herbs (particularly stands of Ataenidia conferta and Thaumatococcus danielli, known locally as mongongo) cover the forest floor. Along the moist bottoms and in swampy headwater regions tall trees are few; palms, woody vines and dense stands of marantaceous herbs predominate making these difficult areas to traverse.

The Effects of Human Occupation It is unknown how long humans have inhabited the Ituri and what patterns of subsistence they may have used to exploit the environment.

The Study Area

11

Largely based upon their small stature and obvious skills at exploiting the forest, it has become the conventional wisdom that Pygmies were living by hunting and gathering in this area for many generations prior to the introduction of agriculture by Bantu some two thousand years ago (Cavalli-Sforza 1977, 1986; Hart 1979; Hiernaux 1977; Murdock 1959; 1968; Tanno 1981; Turnbull 1965a, 1968). We do know that there were humans living in the Ituri region at least as far back as 40,700 B. P., but the ecology of the area was different from what it is today. Excavations by Van Noten at Matupi Cave, which is presently situated within the rain forest, strongly indicate that the area was savanna from before 40,000 until at least 2900 B.P., and possibly as recently as 720 B.P. (Van Noten 1977). Given this evidence, we know that people were living in the geographical region of the Ituri prior to the domestication of plants and animals, but the habitat at the time appears to have been woodland and savanna-not the moist tropical forest of today. Conventional wisdom to the contrary, there exists no convincing evidence that Pygmies or any other people have ever lived entirely by gathering and hunting in an African rain forest environment (Bailey et al. 1989; Bailey and Peacock 1988). As for the antiquity of occupation of the Ituri by agriculturalists, we have no clear date. The upper level at Matupi, dated at 790 B.P., contained Iron Age artifacts which would suggest the presence of agriculturalists by the twelfth century, but we have no evidence of agriculture before that time. However, given what is known about the spread of Bantu and Sudanic languages, iron-working, and pottery, it is very probable that people practicing some form of agriculture have been present in the Ituri region two thousand years or more (David 1980; Ehret 1982; Phillipson 1977). No matter what is the antiquity of occupation, the mixed CynometraBrachystegia forest that is the current mature vegetation type of the northern Ituri has been much disturbed by human occupation over the last few hundred years at least. The presence of agriculturalists practicing long-fallow, shifting, slash-and-burn horticulture has resulted in a present patchwork of climax vegetation mixed with all stages of successional growth. Walking long distances through the forest one realizes the extent to which the forest is variegated by old village sites and their adjacent gardens. Some were apparently cleared so long ago that they are barely distinguishable from the contiguous climax vegetation; others were cleared within the memories of the oldest living people; and some patches of secondary forest were cleared as recently as 1964-{iS when the villagers fled into the forest far from the road and the perilous turmoil of the Simba Rebellion. While some of the old settlement and garden sites are in the advanced stages of succeeding to the mature vegetation

12

Behavioral Ecology of Efe Pygmy Men

type, others, for as yet unknown reasons, are devoid of emergent trees and have generated dense stands of herbaceous growth (these are considered by the Efe to be the habitats favored by the largest game animals, forest buffalo and elephant). Areas cleared more recently are a tangle of lianas and shrubs beneath emerging hardwood trees; and still others are in less advanced stages of succession with large stands of the initial fast-growing emergent known as the parasol tree (Musanga cecropioides). These various seral patches combined with river valleys, swampy headwaters, rock outcroppings, and the most recent village and garden sites near the road, produce a mosaic of diverse habitats that provide cover and food for the greatest biomass of mammalian species in forested Africa (Wilkie 1989). As long as human population densities have remained low and the traditional pattern of shifting horticulture has been sustained, there has been a continuous creation and regeneration of habitats more productive than the climax vegetation type. In secondary habitats, such as those created by shifting agriculture, more of the energy available to the plants is channeled into growth and reproductive parts and less into defensive mechanisms or the maintenance of structural parts (Ricklefs 1973; Odum 1969). Since the reproductive parts-flowers, fruits, and seedsare just those parts that are most edible to insects, birds, and mammals, a greater biomass of faunal species is created. The present patchwork of different successional stages intermixed with climax habitats is a more productive environment, with a greater abundance of animals for human exploitation than the pristine primary tropical rain forest ( e. g., Peterson 1981).

PEOPLES INHABITING THE ITURI FOREST There are currently four populations of Pygmies, collectively called the BaMbuti, living in the Ituri Forest. They are not separate populations in a demographic sense as they are continuously distributed geographically, and they intermarry, but they are differentiated by language and, in many respects, by custom and technology. Many of the differences between the four BaMbuti are attributable to the long-term association each has had with a different tribe of Sudanic- or Bantu-speaking horticulturalist. Each BaMbuti tribe speaks the same language and has many of the same cultural practices as the tribe of village-living horticulturalists with whom it associates. The most-studied BaMbuti by far are those living in the central and southern portions of the Ituri associated with the Bantu-speaking Babila (Harako 1976; Hart 1978, 1979; Ichikawa 1978, 1981; Putnam 1948;

The Study Area

13

Tanno 1976, 1981; Turnbull 1961, 1965a,b, 1968, 1972). The Babila are relatively recent immigrants to the forest, having expanded (or been pushed) from the savanna in the east perhaps as recently as the last two hundred years. The Mbuti have traditional exchange relationships with the Babila (Turnbull 1965b), but in most areas there is also an extensive commercial meat trade whereby outsiders coming from more populated areas walk long distances into the forest to trade food, salt, soap, and cloth for wild game killed by the net-hunting Mbuti (Hart 1978). The Sua (or Tswa) are a population of BaMbuti associated with the Babudu and Bandaka on the western edge of the Ituri (Schebesta 1937). Like the Mbuti, Sua are net-hunters, and they engage in extensive barter with meat traders who come from Wamba. A third population of BaMbuti, called the Aka (but also Tswa), live in association with the Mangbetu and the Azande in the northwest in what is now mostly savanna (Schebesta 1937). There are few Aka left. Many may have fled to the south and east to become Sua and Efe in the late nineteenth century when the Azande and the Arabs took control of the Isiro area (Heim 1979); others may have migrated to other areas as the forest became badly degraded during this century. Of the few Aka that remain, most are now living as settled agriculturalists and wage laborers on the many plantations in the area. A fourth population of BaMbuti, the Efe, have the broadest distribution extending over most of the northern Ituri down to the southeast near Beni. The Efe are associated with the many subtribes of the Sudanicspeaking Mamvu and Lese. They have been described in greatest detail previously by Schebesta (1936, 1937). The subjects of our studies are the Efe living in association with a subtribe of the Lese called the Walese Dese, in the northern Ituri near the forest-savanna ecotone. The Walese, also called the Balese or the Lese by ethnographers and by local people, are referred to throughout this work as Lese. In addition to these four populations of BaMbuti and the tribes of horticulturalists with whom they associate, there are other peoples who in recent years have been immigrating in increasing numbers from the highly populated areas around the forest. While much of the Ituri still has fewer than four inhabitants per square kilometer, it is surrounded by districts that support the highest population densities in all of Zaire outside of the capital, Kinshasa. Running along the southeastern boundary of the Ituri are the rich slopes of the Ruwenzori and the Virungas. This is the most agriculturally productive area in all of Zaire providing large quantities of food that are transported westward through the Ituri to Kisangani and sometimes beyond to Kinshasa. Population growth in these highland districts has been rapid, and competition for land has induced increasing numbers of people (particularly the Banande) to spill

14

Behavioral Ecology of Efe Pygmy Men

down the western slopes into the forest in search of unclaimed land and opportunity. Similarly, competition for land along the northeastern and northern edge of the Ituri-the forest-savanna ecotone--is nearly as intense. Consequently population densities are increasing rapidly along the edges of the forest and along the main road to Kisangani that bisects the Ituri into its northern and southern halves. Large portions of the forest are being cleared for small-scale settlements and cultivation, and meathungry populations are reaching deep into the forest to exploit the animal populations that are now declining measurably (Hart 1978, 1979). Already in some areas, a once-healthy meat trade has collapsed because the forest has been so depleted of animals. In other areas (in the northwest near Wamba and Isiro and in the southeast near Beni) the forest has been degraded to such an extent that the BaMbuti and their shifting agricultural partners have been forced to concede their traditional lands or to live in permanent settlements and work as wage laborers (Bailey 1982). The processes of change that are concomitant with population pressure and commercialization are underway to varying degrees throughout the Ituri. No BaMbuti or villager population has been isolated from these forces nor will they be in the future. We should make every attempt not to ignore or minimize the impact of these factors upon the economic and social relationships of the people. This is particularly important if the results of our research are to have value for making cross-cultural comparisons and for testing hypotheses generated from ecological and evolutionary theory.

THE STUDY AREA AND STUDY POPULATIONS I conducted my research among the Lese and Efe living in the most northern section of the chiefdom (collectivite) of the Walese Dese. The area is sometimes referred to by local residents as Malembi after a small river by the same name. I chose it as a suitable long-term study site in 1978 after surveying eight different Pygmy populations in six countries across central Africa. There are many reasons why Malembi was determined the most desirable site for a long-term project, but most of them relate to the very poor condition of the road that runs through the center of the area and serves as the main means of trade and communication with the rest of Zaire. The road was built by the Belgian administration using primarily local labor in 1943 and it was widened and improved in 1957. Since the Simba Rebellion in 1964--D5 the road has fallen into such a state of disrepair that passage by commercial trucking is prohibi-

The Study Area

15

tively risky. Because of the very poor condition of the road, this area has been largely abandoned by Zairian, Greek or Belgian entrepreneurs interested in establishing or maintaining a commercial enterprise. Several coffee plantations that existed south of Malembi were abandoned in the mid-1960s and have since been reclaimed by the forest. The population densities within and surrounding the study area have remained low in comparison to other areas within the Ituri region. A commercial meat trade has not developed within the Malembi area as it has to the south among the Mbuti and to the west among the Sua and the Efe who live in the area of forest near Wamba. This means that one disrupting influence on the traditional relationship between village farmer and BaMbuti is not operating in the study area. Another potential disrupting influence, coffee plantations, does exist on the edge of the study area to the north. Several Lese and Efe who live within the area, but who were not part of the behavioral samples, periodically work as casual laborers on the plantations. For the most part, however, the traditional economic system, whereby Lese practice slash-and-burn horticulture to raise subsistence crops to trade with the Efe for forest products and labor, continues to be the mode of subsistence for the people within our study area. This will continue to be true as long as the road remains in its present deteriorated state and as long as large areas of forest to the east and west remain inaccessible to commercial exploitation.

Sample Populations The total number of village-living horticulturalists within the overall chiefdom of the Lese Dese is approximately 2,300; of these about 1,900 are Lese Dese and the rest are from other Bantu- and Sudanic-speaking tribes. The total number of Efe in the chiefdom varies widely, but approximately 1,000 Efe live in association with the 1,900 Lese at any one time. Our studies concentrate on 14 Lese villages stretched along 18 kilometers of road from Malembi to Dingbo. These villages range in size from 15 to 100 people and the total number of horticulturalists living in them is approximately 550. At anyone time, up to 470 Efe may be living in association with these 14 villages. The demographic data presented in this study come from reproductive and marital histories collected mainly from these 550 and 470 people. Most of my research other than demography and anthropometry focuses on a subsample of villages that are within walking distance of the research station, called Ngodingodi. This station was established by myself (with a great deal of help from all the local people) in April, 1980. Within three kilometers of Ngodingodi there are five Lese villages with

16

Behavioral Ecology of Efe Pygmy Men

140 to 190 residents. These were the foci of studies of the behavioral ecology of the Lese conducted by Ross and Wrangham from November, 1980, through August, 1981. During the course of my research, from March, 1980, through January, 1982, the number of Efe living in association with the five villages that comprised the target study area varied from 70 to 140 people. They were distributed among three to seven temporary living sites that were placed in or near the villages or in the forest up to an eight-hour walk from the road. This amount of variation in the number of Efe living in an area is not unusual; entire bands frequently move several days' walking distance to another area to establish, or more usually reestablish, an affiliation with another village (Bailey and Peacock 1988). My most intensive studies focused upon the Efe men who were members of two different but affiliated bands, the Andikodi and the Andikeke, who had long-term traditional exchange relationships with four of the five villages studied by Ross and Wrangham. When I started behavioral observations there were 14 men in the two bands. I included all of these men in the sample for purposes of behavioral observations. During the course of the study, most of these men migrated in and out of the area, as did other men who were not in the original sample but who were added later. In the end, 16 Efe men became the principal subjects of my focal behavioral observations (see Chapter 2 for methods). The Lese Dese The first mention of the Lese by early European explorers is by Henry Morton Stanley, who describes the Lese settlements he raided during his expedition across the Congo to "rescue" Emin Pasha (Stanley 1890). There are several brief reports on the history and cultivation practices of the Lese by early Belgian administrators (see Geluwe 1957), the most complete and reliable by far being that of Baltus (1949). One brief ethnography has been published by Joset (1949). Grinker's (1989) dissertation is the most complete ethnographic account of the Lese Dese. He studied the Lese who are the trading partners of the Efe bands I worked with, and his research focused on seeing the Efe-Lese relationship from the villager point of view. Schebesta's extensive accounts of the Efe contain some information concerning their "patrons," the Lese (Schebesta 1936, 1937). According to several sources, the Lese were originally pastoralists who were pushed into the forest some two hundred years ago as a result of the Zande expansion (Joset 1949; Geluwe 1957). There is actually little information to support such a notion, especially since the Azande did not appreciably disturb the Mangbetu and other peoples to the

The Study Area

17

immediate north of the Lese until after 1870, and the Lese were well established in the forest long before that time (Keirn 1979). Indeed, there is considerable circumstantial evidence to indicate that the Lese have inhabited the Ituri longer than the other horticultural groups residing there now. The current distribution of all the Lese subtribes covers most of the Ituri Forest, but it is discontinuous where other groups (e.g., the Banande in the south and the Babila in the center) have more recently made incursions along the main tracks and trade routes. All of these recent immigrants maintain many more of the vestiges of their savanna and highland origins than do the Lese, such as round house structures, more intensive cropping techniques and more elaborate food processing (Geluwe 1960). Given the current distribution of the different linguistic and tribal groups in the Ituri, it makes most sense that for several hundred years peoples speaking Sudanic languages belonging to the Mamvu-Lese group were living in small, shifting settlements that were sparsely, but continuously distributed from the Bomakande River on the forest-savanna edge south to a latitude as far as Beni. These people probably differentiated themselves from others mainly on the basis of language, since they had no tribal organization, no centralized authority, and probably no tribal identity beyond that which came from forming loose alliances based upon kinship and marriage between neighboring villages. Hard evidence for this view of the distribution and social organization of horticulturalists in the northern !turi is lacking. We can be quite confident that until 1924-1927 when the Belgians imposed a system of petty chieftainships, the Lese and Mamvu lived in small, shifting settlements dispersed throughout the forest and organized on the basis of segmented patrilineages (Baltus 1949; Geluwe 1957). The people who are today called the Lese Dese, for example, are an amalgamation of some fourteen lineages that were spread across the northern Ituri until 1943 when they were forced together along the Mambasa-Mungbere road by the Belgians. Most of the Lese Dese were brought by the Belgians from the area of forest to the west of the current road. After Zaire obtained independence in 1960, approximately 25 percent of these Lese Dese returned to their traditional lands several days' walk west from the road to live in small shifting forest villages. During the 1980s, but after my study was completed, most of these "forest Lese" were forced by the authorities to move back to the road again. Throughout my study and still today Lese who reside along the road make periodic and sometimes extended trips to the forest villages to visit relatives, hide from the police, hunt elephant and other game, trade with the Babudu near Wamba, or just relax and get away from the whirligig of the road.

18

Behavioral Ecology of Efe Pygmy Men

Some other people who are also now called Lese Dese were originally settled in the area of forest that is now traversed by the road and to the east. Some of the lineages with whom these people were closely tied were forced out of the forest to another road some two days' walk to the northeast near Baitebe, and others were taken south to what is now the chiefdom of the Lese Karo. Therefore, these Lese Dese make periodic and extended visits to Baitebe in the north and to Nduye in the south, and their traditional lands comprise the forest and patches of savanna to the northeast of the road. Their identities and allegiances, as well as those of the people living within other Belgian-formed subtribes of the Mamvu and Lese, are based less upon their affiliation to the Lese Dese than upon their particular segmented lineage and the land that the lineage has traditionally exploited. The Lese along the road within my study area still live in small villages of 15 to 100 people. Residence is mainly virilocal, and settlements are composed of patriclans segmented into shallow lineages. Wives were once obtained principally through "sister exchange," but now payment of bridewealth is the preferred method of marriage. Within the study area 21 percent of Lese men are married polygynously, and the maximum number of wives married to one man is four. Except for the chieftainship which tends to remain within the same lineage, there are neither inherited offices nor sources of inherited wealth. Gardens are cleared by men within several hundred yards of the village and cultivated for one to two years before a new patch of climax or late successional forest is cleared. Each year each household clears an average of 0.35 hectares of land. They cultivate primarily cassava and bananas for subsistence and peanuts and rice as cash crops. These cash crops and small amounts of coffee are sold to the few merchants who are willing to expose their vehicles to the treacherous conditions of the road. Average annual income per Lese household is less than $50 (u. s.). Once gardens are cleared, most, but by no means all, of the labor put into planting, weeding, harvesting, and processing the crops is done by women. In addition to cassava, bananas, peanuts, and rice, the Lese also cultivate sweet potato, corn, squash, beans, sesame, and occasionally taro and yams. Their primary source of fat is oil from the palm, Elaeis guineensis, which is cooked with the leaves of cassava to produce a staple called sombe. Meat and fish are also cooked with palm oil. Although fishing in the small streams around the village is a frequent and favorite activity of Lese women, fish do not account for a significant proportion of their diet. Most Lese own a few chickens, but only four households out of approximately two hundred own goats and none own pigs. Domestic animals are not slaughtered except on rare ritual occasions and are thus not a regular source of meat. Meat is acquired by a

The Study Area

19

few Lese by using snares which are set in the forest within ten kilometers of the village. During my study, over half of the meat eaten by Lese came from Efe to whom Lese give cultivated food or other material goods in return.

The Efe The Efe are mentioned by the earliest Europeans to reach the northern Ituri area (Schweinfurth 1874; Pasha 1888; Stanley 1890; Casati 1891; Junkers 1892). Before the lturi Project began, they were most studied by Schebesta (1936, 1937), who spent several weeks in 1930 at, among other places, Nduye, just 65 km south of our study site. Harako's (1976) study at Lolwa compared the hunting patterns of a band of net-hunting Mbuti with a band of Efe archers. Tereshima (1983) studied several bands of Efe east of Nduye near Andili in 1978-1979. Like Harako, he concentrated his research on hunting, and his results suggest that Efe archers are as efficient as Mbuti net-hunters. Turnbull (1965a, b) included observations of Efe settlement patterns and social organization which served as comparisons to similar information on Mbuti. The Efe live in small temporary encampments of three to fifty residents. The size and composition of camps are very flexible, divisions occuring at the level of the household; however, residence is primarily viripatrilocal and most camps are composed of loose patriclans. For example, censuses from 18 Efe camps show 83 percent of men residing in their patriclan and 87 percent of married women residing with their husband's patriclan. In another study (Terashima 1985), 33 of 39 (85%) Efe households were found to reside with the husband's patriclan. Murdock coded Mbuti as without "any patrilineal kin groups and also (without) patrilineal exogamy" (Murdock 1967:157). The Efe identify themselves by patriclan and can trace their ancestry back two to four generations, identifying each forebearer, male or female, by patriclan. Marriage is forbidden within the patriclans of either the mother or father. Ideally, marriage is by sister exchange, but only 40 percent of Efe men are able to achieve this ideal, which makes disputes over marriage and children frequent and, in many cases, they endure for generations. Bridewealth is absent, and bride service is very brief when it occurs at all. For approximately seven months during the year, temporary camps are situated near the Lese villages often on the edge of the forest near an active or recently abandoned garden. During the other five months Efe camp deeper in the forest, but never in my experience more than an eight-hour walk from a village. When they are living in the forest, Efe move camp approximately every two weeks. Actual camp sites are

20

Behavioral Ecology of Efe Pygmy Men

changed less frequently when they are near the villages, but the number and composition of individuals at anyone site is more variable because individual households tend to change residence more often. Throughout the year Efe gain their subsistence from both forest resources and cultivated foods. The great majority of Efe do not cultivate crops themselves and none that I studied had gardens at any time during my research. The Efe hunt and gather forest resources for their own consumption and for exchange with villagers. Meat, honey, a few gathered fruits and nuts, and building materials are brought from the forest to the villages to exchange for cultivated foods, tobacco, cannabis, and material goods-primarily cloth and iron implements. Efe also provide labor to Lese and receive food and goods in return usually the same day. Most of the labor is supplied by Efe women who assist villager women in their many tasks relating to food production and processing. On a typical day in an Efe village camp, the majority of the Efe women will spend at least a portion of the day in the villagers' gardens, and in a forest camp at least a few of the women will go to the village; those that remain behind might fish or gather some forest foods. Efe men, on the other hand, work for villagers infrequently-primarily to help Lese men clear their gardens-and spend most of their subsistence-related activities in the forest. Unlike the net-hunters to the south where Mbuti women serve as beaters during the hunt, Efe women do not take part in the hunt except on extremely rare occasions. Hunting and honey collection are almost exclusively male activities, while gathering is done by both sexes. Men hunt alone or in cooperative groups ranging in size from 4 to 27 men. Their most frequent prey are the six species of duikers (Cephalophus spp.), the water chevrotain (Hyemoschus aquaticus), and monkeys. Men most often find beehives when they are alone in the forest, but they generally wait until a later time to extract the honey with a small number of other men. (For accurate descriptions of detecting and extracting honey see Ichikawa 1981.)

THE ANNUAL CYCLE In the area where our studies are conducted, at approximately 2°15' N. latitude, there is a dry season lasting roughly three months, December through February. During each of these three months rainfall is generally less than 1/30 of the annual total. However, there is variation from one year to the next in the onset and duration of the dry season. In some years, this variation disrupts the annual cycle of many biological systems within the environment. Of greatest concern to the Lese and Efe, and about which they have considerable anxiety, are the effects of this irregular variation upon domestic and forest food production.

The Study Area

21

The cultivation cycle of the Lese is superimposed on the annual rainfall cycle. Lese clear their gardens early in the dry season so that felled vegetation can dry and be burned prior to the onset of rains. They plant bananas and cassava as they clear the gardens in December, but most crops are planted in late March and April (after the fields have been burned) in order to take advantage of the early rains, which facilitate the germination and growth of seeds. The harvest begins in late June and is more or less continuous, depending on the particular crop, through December. There are two periods during which this annual cycle is especially vulnerable to the irregular variation in rainfall. If the rains come earlier than expected, the felled vegetation cannot be burned and must be cut and cleared by hand. This method not only results in smaller gardens, but it also reduces the amount of ash that is added to the soil. If the rains come later than expected, germination and growth of the seeds planted in March and April are inhibited. In either case-early or late onset of the rainy season-the crop yield can be precariously reduced. A reduction in the crop yield generally does not have serious effects on food availability until April, May and early June of the following year-just prior to the harvest of the next year's crops. By that time the peanuts, rice, corn, and other crops that were stored at the previous harvest have been depleted. The people are forced to subsist on the cassava and bananas that remain in their gardens. However, if the area planted the previous year was small, then even these staples become in short supply and the resources available cannot satisfy nutritional requirements. This pattern is by no means unique to the Lese; many agriculturalists undergo a period of seasonal food shortage that is generally most pronounced just prior to harvest (Miracle 1967). For the Lese, a shortage does not occur every year, but only during those unpredictable years when the rains do not follow their normal pattern. During such years, however, the shortage can be severe resulting in caloric deprivation and weight loss for most people in the area (Bailey and Peacock 1988; Ellison, Peacock and Lager 1986; Jenike 1988).

The Efe Annual Cycle To the extent that they are independent of agricultural subsistence and reliant upon forest food resources, the Efe might be insulated from the effects of unpredictable shortages of domestic food. If, for example, the forest had a different seasonal pattern of food production, then the effects of fluctuations in agricultural food availability could be mitigated by exploitation of the forest resources. Since they could supplement their diet with forest fruits, nuts and tubers, the Efe would be at an advantage

22

Behavioral Ecology of Efe Pygmy Men

during a period of agricultural food shortage. To some extent the Efe are able to do this. Unfortunately, however, the annual cycle offood production in the forest coincides closely with that of the Lese gardens. Food in the forest is most abundant just when it is most plentiful in the villages-from late June until mid-September (Hart and Hart 1986). This is not only the honey season, anticipated with great enthusiasm by all Efe, but also a period when most edible fruits and nuts (n.b., Canarium schweinfurthii) are available. To take advantage of the plentiful resources, the Efe move their camps into the forest while continuing to make frequent day trips to the Lese villages to trade honey and meat and to assist in harvesting and processing peanuts. By late September, the honey from most of the beehives within a band's range has been extracted, many of the rivers have overflowed their banks, and the forest has become uncomfortably wet. Since there is also plenty of food available near the villages, the Efe move their camps back to the edge of the village gardens. While Efe women assist the villagers in the gardens, Efe men spend most days hunting from the village camps. During the dry season, Efe men may assist the Lese in clearing next year's garden while the women help in the rice harvest. By February, the forest has become very dry, the rice harvest is nearly completed, and Efe begin moving back into the forest for the hunting season. The hunting is good from January to March because the rivers are low and the water chevrotain (Hyemoschus aquatic us) cannot hide up under the banks effectively; also, duikers (Cephalophus spp.) will come to feed under the few fruiting trees, where hunters can perch and wait in ambush. By the time the Efe emerge from the forest to settle near the village again in April, food in the gardens may already be in short supply. If so, the Lese may not be as generous as they once were when it comes to trading meat for starch or paying Efe women with food for work in the gardens. Efe women may be forced to forage in old gardens for the remnants of long-abandoned cassava and sweet potato plants. Although the Efe are not above stealing at any time during the year, the frequency of theft from the Lese gardens is greater in April and May, and villagers are more motivated to ferret out thieves at this time. Conflicts between Efe and Lese may become frequent and it is during this period of the year that the Efe are most likely to change their affiliation with a particular village, often citing the lack of food as the reason for their abandonment of one village for another. It is also during the April-June period that the Lese and Efe are most likely to be nutritionally stressed. In 1980 and again in 1983 and 1985 widespread hunger became apparent. The people were noticeably thinner and lost significant amounts of weight (Jenike 1988); their skin was

The Study Area

23

dull; overt symptoms of infectious diseases (especially malaria) were more prevalent; conflicts over food were more frequent; and the Kiswahili word for hunger, "njala," was often spoken. All of these phenomena were remarked upon by the people themselves during and after these periods. In our experience, Efe have been less susceptible than the Lese to variable seasonal food shortages. This is because the Efe are able to take advantage of the variation between areas in food production by remaining mobile and maintaining affiliations with several widespread Lese and Mamvu villages. When there is a chance shortfall in food production in one area in one year, Efe are able to move several days across the forest to villages where food is more plentiful. Lese, on the other hand, by nature of their sedentary subsistence system, are obliged to remain close to their gardens to endure periods of low food supply in their villages. Consequently, they have experienced greater proportional weight loss during these difficult times (Bailey and Peacock 1988). From our experience we know that seasonal food shortages occurring from April to June during occasional unpredictable years have widespread consequences for many aspects of Efe and Lese life including their activity patterns, social relationships, reproductive physiology, and demography. We are just now beginning to discover precisely what the effects are and their magnitude (e. g., Bailey 1989b; Ellison and Peacock 1989; Jenike and Bailey 1989). Our studies in the Ituri continue with these sources of longitudinal variability very much in mind. With reference to the work reported here, the reader should keep in mind that such long-term variation exists and that, with the possible exception of the demographic compositions of the populations, my results represent less than two years in a socioecological setting that is ever-changing.

3 Methods

OBSERVATIONS OF BEHAVIOR Choice of Observation Technique There are numerous anthropological studies that have attempted to quantify human activities and social relationships. Most of them have used what have come to be called spot or scan sampling techniques (e.g., Whiting and Whiting 1975; Johnson 1975; Hames 1978; Gross et al. 1979; Flinn 1983; Wrangham and Ross 1983; Borgerhoff-Mulder and Caro 1985). By this method the observer records the activities and states of all the individuals present at a location at one instant in time. Spot and scan sampling can be a very efficient means of collecting a large sample of behavioral data on a large sample of individuals. It is an appropriate method for quantifying activities and spatial relationships in the sort of setting where it has been used most: primarily in small villages where people tend to be distributed in groups in relatively accessible and predictable places. Using the scan sampling technique in the case of Efe would not have been an efficient use of our time, nor would we have been able to collect a representative sample of Efe behaviors. Efe, except in the early morning or evening when they are apt to be in their camps, do not distribute

25

26

Behavioral Ecology of Efe Pygmy Men

themselves in either predictable or accessible places. Even late in the study, when I was most familiar with how Efe men spend their days, I could never accurately predict how or where a man would spend the next day. (Indeed, I believe an Efe man himself could not predict how he would spend the next day.) Since Efe men and women travel over very wide distances, in the forest or among several Lese villages, alone or in small groups, scan sampling was not an appropriate means of collecting behavioral data on a number of indi viduals. Under such conditions I could make a much more efficient use of time by remaining with one focal subject for a considerable period of time recording numerous observations before moving on to the next subject. This method could increase the amount of observation time per unit of total study time, since the relative amount of time between subjects would be reduced. Instead of observing just one short moment in a subject's day and then moving on to the next subject, these focal observation periods had the added advantage of allowing me to witness a sequence of behaviors and have a better knowledge of the context of any one event. Ultimately, I chose one hour as the duration of one focal observation period as a compromise between several considerations: the logistics of contacting subjects; the number of independent observation periods necessary to discover behavioral differences between individuals; my own attention span under sometimes arduous physical conditions; and the amount of time I felt the subjects could tolerate being closely observed without significantly altering their behavior.

Sampling Schedules I followed each subject for a one-hour sampling period. Subjects for the observational study were determined by the presence at the beginning of the study of 16 men in each of two bands close to the research station. During the course of the study the composition of the two bands changed as men moved in or out of the area, so that some men were dropped from the sample and in some cases picked up again and others were added. I attempted to obtain eight one-hour focal follows on each man during each of four "seasons" between January, 1981, and January, 1982. A "season" was determined by the movements and activities of the Efe and did not have a strict correspondence to the calendar year. Seasons I and III were, respectively, the "hunting" and "honey" seasons when the Efe were settled predominantly in forest camps more than 50 minutes' walk from a village. Seasons II and IV were periods when the Efe settled in camps near a village ("village camps"), often on the edge of old or current gardens. The eight one-hour focal follows on each

27

Methods

subject during each season were evenly distributed over four three-hour time blocks beginning at 6:00 a.m. and ending at 6:00 p.m. See Table 3.1 for a breakdown of the numbers of observations during each season on each man. Although I made a strong effort to obtain an equal number of observations during each season, this proved impossible due to the movements of the men into and out of the area. TABLE 3.1 The Number of One-Hour Behavioral Observations Collected During Each of Four Seasons on Each Efe Man

I.D.# 530 531 532 533 534 538 630 631 632 633 634 635 636 650 656 670 Totals

Forest Season I

Village Season I

Forest Season II

Village Season II

8 8 8 8 0 0 8

8 8 8 8 8 8 8 8 0 8 8 8 8 8 8 0

8 8 8 0 0 8 8

0 8

8 8 0 0 8 0 0 0 8 8 0 8 0 0 8 0

0 8 8 8 8 8 8 8

104

56

112

104

8 8 8 8 8 8 8

8

In order to eliminate possible bias in the selection of subjects during certain observation periods, a random order of unique identification numbers was generated at the beginning of each season for each time block. Men were observed in that random order unless the observation would be a violation of the following rules, designed to increase the independence of observations of the same subject:

1. A subject could not be observed twice within the same time block. 2. A subject could not be observed during two consecutive time blocks. A natural corollary of these rules is that no subject could be observed during more than two observation periods in the same day. If a subject

28

Behavioral Ecology of Efe Pygmy Men

came up in the random order and one of these rules was violated, that subject was replaced at the end of the order and the next subject was chosen. If a subject was not present when it was suitable to begin an observation period and I could not reach him before the end of the time block, then that subject was replaced at the end of the random order, and the next subject in the random order was chosen. If two subjects were placed at the end of the order in this way, then no observations could be made during that period. To be able to later check for possible biases in the observations that were "missed" in this way, I noted the probable location and gross activity of the subject and cross-checked this information with informants and the subject himself. The number of missed observations were minimized by anticipating who was coming up in the random order and determining where they were likely to be at the start of the observation period. Nevertheless, the Efe did not always conform to my best-laid plans, and, particularly when men went into the forest alone for many hours at a time, not being able to reach them by the end of the time block was unavoidable. The days when I recorded behavioral observations were determined predominantly by factors independent of my knowledge of what the Efe were doing that day. Except when I was sick or performing other research activities, I performed focal observations whenever possible within the constraints of the sampling schedule. There was a temptation to sample particular Efe men during particular activities or in particular settings either because the results would then conform to my own subjective notion of what Efe men do, or because I would enjoy the observation period more; but I made every effort not to bias what was designed to be a random, and thereby representative, sample of the behavior of a group of Efe men during 1981.

Recording Methods The one-hour focal observations combined both continuous and point (instantaneous) sampling techniques (Altmann 1974). A digital watch with stopwatch and time-interval functions was used. Every minute on the minute (one-minute point sampling) I recorded the focal subject's following states or behaviors (headers appearing on the checksheet shown in Appendix 2 are in parentheses; for a complete list of codes used in recording observations, see Appendix 3): (1) The type of food being eaten (FOOD CON); (2) posture (po) including both stationary and mobile states; (3) habitat or location type (HA); (4) the weight category of the load (LO) carried; (5) the activity (ACT) engaged in consisting of a grammatical sequence of verb-object codes; (6) responsibility for a cook-

Methods

29

ing pot (CK) on a fire; (7) social interactions (soc INT) including the interactant and the type of interaction; (8) nearest neighbor (NN) if within 10 meters; (9) speaking or listening to another person (TALK) including the identification number of the person, if known; (10) type of child care and the child involved (CHILD); (11) the type of weapon (w) carried. Among the many advantages to this recording system was that I was not restricted to recording just one activity on an interval; rather it was possible to record several simultaneously occurring activities. For example, if a man were sitting in camp sharpening an arrow while at the same time holding an infant, roasting some manioc on the fire, smoking a cigarette, and talking to his brother, all of these behaviors could be recorded easily. In this example under po I would enter s to designate sitting; under ACT I would enter RPAR to designate repairing an arrow; under CHILD I would enter 1 for engaged in child care; under CK I would enter 1 to designate food on the fire; under CON I would enter FU for smoking tobacco; and under TALK I would enter A631 to designate his talking to his brother whose identification number was 631The system was designed to provide data on the frequencies and, in some cases, the rates of occurrence of specific behaviors and to allow estimation of the proportions of time men spent in various activities. I recorded all the observations that did not occur in a camp into a microcassette tape recorder and later (within 48 hours) transcribed them onto the checksheets. Observations in camps were recorded directly onto the checksheets. In order to study patterns of food sharing and to quantify food consumption, I recorded continuous observations of food exchange (FOOD EX), including the name of the food and the person giving or receiving the food. The amount and name of food being consumed was recorded under the category FOOD CON. At the start of each focal observation hour I recorded the health status (HE) of the subject. Every 30 minutes-at the beginning, middle, and end of each observation hour-I recorded the weather (WE) (raining or not raining), and all the individuals within ten meters of the focal subject (CR). At the end of each half-hour the distance traveled by the focal subject was recorded. To increase the accuracy of the distance estimates I practiced estimating and later measuring various distances, and I measured and mapped many of the well-traveled paths within the study area.

All-Day Observations of Behavior From one-hour focal observations it is possible to extrapolate daily frequencies of activities by multiplying hourly occurrences by the appro-