Bonobos and people at Wamba : 50 years of research

This book reviews all the findings about bonobos and the local people of Wamba village in the Luo Scientific Reserve in the Democratic Republic of the Congo over the last 50 years. In 1973, Takayoshi Kano, a Japanese primatologist, traveled across a vast area of the Congo Basin with a bicycle and found Wamba village to be a promising site to start his first studies on wild bonobos. Since then, many researchers from Japan and all over the world have been working at Wamba, now the longest standing study site, to uncover various aspects of the ecology and behavior of this most recently identified great ape species. The researchers study bonobo behaviors and carry out various activities for the conservation of bonobos. They also conduct anthropological studies of local people who live with bonobos and believe them to be distant relatives from the same family, living in the forest. This book is published in commemoration of 2023 marking the 50th year of study. The main chapters are contributed by active researchers studying bonobos and the local people at Wamba. The book also includes contributions from various eminent researchers who have carried out short-term research or have supported research at Wamba, which helps place these studies of bonobos in a broader primatological or anthropological perspective. This book will be a useful resource for professional researchers in primatology and anthropology, as well as graduate or undergraduate students interested in these research fields. Foreword Introduction Contents Contributors Part I: Dawn of Bonobo Research A Journey to Discover Wamba Prologue From Mbandaka to Ikela: A Journey by Peugeot From Yaloya Church and Lake Benait to Yalosidi From Yalosidi to Kele Seeing a Bonobo for the First Time A New Beginning with Bicycle: A Trip to Bokungu To Djolu: Imprisoned in Bokondo Mishap at Bolamba Finally, to Wamba Bonobos in Wamba Epilogue From the Early Days of Bonobo Research The Road to Wamba From the First Survey to Success in Feeding Bonobos From the New Version of “The Pygmy Chimpanzee” Turbulent Times for Bonobos in Wamba Trends in Bonobo Research Through the 1990s and Name Change E Group’s Fission and Changes in Intergroup Relations Kame and Her Sons Poaching Incidents News of Other E-Group Members Growth Retardation and the Desire for Sharing Interests Bonobo-ness? References Science’s Early Reception of a “New” Ape References Column: Mongo Forest Column: Wamba—Base Camp for My Study in Zaïre References Column: Following Bonobos in the Forest Column: Researchers Are Part of the Wamba Ecosystem Part II: Physiology and Genetics Sexual Behaviors and Hormonal Background of Female Bonobos Introduction Sexual Swelling Cycle Sex Hormone Dynamics Relation Between Maximal Swelling Phase (MSP) and Ovulation Prolonged Sexual Receptivity Sexual Swelling and GG Rubbing Why Is Sexual Receptivity Prolonged in Female Bonobos? Conclusion References Personality Quirks and Polymorphic Genes in Bonobos Introduction: What Is Personality, and How to Study It? Primate Personalities Why Study Bonobo Personality? What Did We Learn About the Personalities of Wamba Bonobos? The Genetics of Personality What Did Wamba Bonobos Reveal About the Genetics of Three Personality-Related Genes? Conclusions References Within- and Between-Group Kin Structure of Wild Bonobos in Comparison to Other African Great Apes Introduction Methodology for Analysis of Kinship Noninvasive DNA Sampling Autosomal and Y-chromosomal Microsatellite Analysis Mitochondrial DNA Analysis Kin Structure Within Groups Male Reproductive Skew Kinship Among Philopatric Males Kinship Among Immigrant Females Kin Structure Among Neighboring Groups Male Gene Flow Between Groups Kinship Among Males of Neighboring Groups Kinship Among Females of Neighboring Groups Social Systems of Bonobos with Respect to Kin Structure Conclusions Materials and Methods References Part III: Behavior and Development Hunting and Meat-Eating Behaviors of Bonobos at Wamba: Comparison with Other Bonobo Study Sites Introduction Frequency of Meat-Eating Prey Preferences Hunting Techniques and Meat Transfer Comparison with Chimpanzees Conclusion References The Puzzle of Pan Tool Use: Why Are Bonobos So Different from Chimpanzees in Their Use of Tools? Introduction Tool Use at Wamba and Other Sites Bonobos and Chimpanzees Compared Testing the Main Hypotheses for Tool Use Extrinsic and Intrinsic Drivers of Tool Use Sex Differences in Object Manipulation Future Directions Conclusions References A Closer Look at Grooming Patterns in Bonobos Introduction Body Site and Body Orientation Preferences Hygienic Functions of Social Grooming Social Functions of Social Grooming Mutual Grooming and Polyadic Grooming Conclusion References Bonobo Gestures, Meanings, and Context Introduction The Gesture That Rocked the Boat New Gesture Just Dropped The Gestures Were There All Along Gesture Reloaded Up Next in Gesture Research (Conclusion) References Multiple Phases of Natal Transfer Process in Female Bonobos and Factors Underlying Each Phase: Findings from Long-Term Observations in Wild Populations Introduction Long-Term Data Collection and Management Bonobo Groups at Wamba Individual Daily Presence Records Definition of Terms Data Processing Documenting Emigration/Immigration Events Overview of Collected Demographic Data Relations with Intergroup Encounters Destination of the Females Who Have Dispersed from Their Natal Group Temporal Flow of the Female Transfer Process Age at Emigration and Immigration Duration of Temporary Breakaways and Visits Interval from Immigration to First Parturition Age at First Parturition Proximate Mechanisms Underlying Each Transfer Phase Pre-Dispersal Phase: Developmental Thresholds Independence from Mothers Pubertal Changes Dispersal Phase: Role of Intergroup Encounters in Dispersal Decision Pre-Settlement Phase: Female Preferences for New Groups Decreased Risk of Secondary Transfer Social Advantage Due to the Presence of Native Conspecifics Settlement Phase: How to Acquire New Group Membership Conclusions References Social Behaviors of Nulliparous Adolescent Female Bonobos Introduction Wamba E Group Behaviors of Adolescent Females Before Migration Wandering After Emigration Behaviors of Adolescent Females After Immigration Relationships Between Adolescent Females and SSFs Conclusion References Column: What Kinds of Sexual Functions Does Genito-Genital Rubbing Have as a Sociosexual Behavior? References Column: Food Sharing in Rich Environments References Column: Staying Together References Column: Exploring Bonobo Habitat Use in Wamba: Findings and Implications References Part IV: Social Relationships Aggressive Behaviors and Social Dominance in Bonobos Introduction Behavioral Components of Aggression Aggressive Behaviors Reactions of the Recipients of Aggressive Behavior Reaction of Bystanders Context and Function of Aggression Food Resources Mating Opportunities Social Dominance and Coalition Formation Dominance Among Males and Agonistic Support by Mothers Female Superiority Over Males and Importance of Female–Female Cooperation Inter-Group Aggression 3–2-6 Severity of Aggression Post-Conflict Behaviors Conclusion References Social Relationships in Female Bonobos Introduction Female Social Relationships Indicated in Dyadic Grooming Female Social Relationships Found in Sexual Interactions and the Distribution of Neighboring Individuals Conclusions Methods References Intermale Relationships in Wild Bonobos at Wamba Introduction Development and Changes in Social Relationships with Mothers and Other Group Members Male Philopatry and Intergroup Relationships Affiliative Relationships Among Males Agonistic Interactions Between Males Changes in Alpha Females and Alpha Males Competition for Reproductive Success Conclusion References Potential Benefits of Intergroup Associations and Chronological Changes of Intergroup Relationships in Bonobos Introduction Reduced Food Competition: A Prerequisite for Intergroup Associations Benefits of Intergroup Associations Variations in Intergroup Interactions Chronological Changes in Intergroup Relationships Human Disturbance and Impact of Habituation Conclusion References Column: From Nests and Videos to Wamba Bonobos References Column: Intergroup Aggression in Bonobos at Wamba Reference Part V: Coexistence of Local People and Bonobos History of Anthropological Studies Around Wamba Introduction Description of the Bongando People Distribution, Language, and Name of the Bongando Ethnic Group Ecological Environment Subsistence Activities Agriculture Hunting Fishing Gathering Animal Husbandry Wage Labor and Commerce Social Structure Lineage System Kinship and Marriage Religion and Other Cultural Characteristics Past Studies on the Bongando Linguistic Studies Anthropological Studies Ethnography in the Colonial Era Anthropological Studies After Independence Conclusion References Subsistence Activities and Forest Utilization among the Bongando People Before and After the Congo War Introduction Changes in Subsistence Activities Related to Fauna A Dual Life in the Village and the Forest Changes in the Prevalence of Hunting Methods Decrease in Animal Population, Increase in Snare Traps Changes in Fishing Methods Less Time-Consuming, more Reliable Changes in Subsistence Activities Related to Flora General Description of Agriculture Homemade Spirits: A Replacement for Cash Crops The Commercialization of Non-Timber Forest Products Commercial Activities by Local People Discussion Impact on Fauna Impacts on Flora The Potential of Lepidopteran Larvae as a Sustainable Source of Income Conclusion Method References Change of the Distribution Network around the Wamba Region Introduction Distribution Network in DR Congo up to Congo War Colonial Era Independence and Beyond Congo War Recent Trade Activities around Wamba Region Change of Distribution Network around Wamba River Trade with Mbandaka Land Trade with Kisangani Area Growth of Local Markets Long-Distance Peddling Discussion Current Status of Trade Activities around the Wamba Region Possibility of Local Products Autogenous Economic Order and Local Actors Conclusion Subjects and Methods Appendix: Detailed Description of Long-Distance Peddling Determining the Route of the “Forest Road” Accompanying long-distance peddling References Empowering Local Associations for Sustainable Local Development: The Case of a Collaborative Project in the Wamba Region Introduction Roles and Characteristics of Local Associations in Africa A Case of Collaborative Development Project in Wamba Region Process and Results of River Transport Project Impacts of the Project and Socio-Economic Change in the Local Community Discussion and Conclusion Methods References Taboo Against Eating Bonobos and Its Degradation Introduction Taboo Against Eating Bonobos Among the Bongando Wildlife Conservation and Traditional Ecological Knowledge Food Taboo Among the Bongando Legend of Bonobo and Bonobo Conservation Current Status of Bonobo Hunting around Wamba Differences by Age Differences by Areas Situation of Bonobo Eating Situation of Hunting and Dismantling Bonobos Factors behind the Start of Bonobo Hunting Impact of the Congo War Interaction with Other Ethnic Groups Obtaining Guns Discussion Current Status of Food Taboos among the Bongando Interpreting Tradition of Taboo to “Cultural Resource” Recalling Tradition through Research Activities Conclusion Subject and Method References The Importance of Monitoring Bonobos and Their Habitats for Informing Bonobo-Specific Conservation Prioritization and Planning Introduction Habitat Use of Bonobos in Wamba Habitat Selection by Bonobos in Wamba for Ranging, Feeding, and Night-Sleeping Seasonality of the Habitat Use and Effects of Food Availability Value of Inundated Swamp Forests for Bonobos The Effects of War and Conflict on Bonobos and Forest Habitats Mapping Bonobo Suitability Range-Wide Conclusion References Column: A Bonobo Funeral—Relationships Between Researchers and Local People as Exemplified in a Funeral Speech References Column: My First Ever Conservation Practice with African Great Apes—Bonobos in Wamba Column: Re-considering The Potential Geographic Distribution of Great Apes for Conservation Action: What is Suitable? References Part VI: Evolution of Bonobos The Influence of the Congo River on the Evolutionary Trajectory of Bonobos Introduction Review of the Congo River History Origin of the Current Congo Basin Topography Brief Description of the Formation of the Current Congo River Hypothesis Postscript to the Congo River History Hypothesis on the Origin of Bonobos Fluctuations in River Discharge Indicated by Changes in Dinoflagellate Communities in Deep-Sea Fan Sediments The Aridity Phases in the Congo Basin Concerning the History of Bonobos Where They Crossed: The Lualaba River Rapids Verifications and Implications of the “Origin of Bonobos” Hypothesis Admixture Between Bonobos and Other Pan Lineages Population Bottleneck Implications for the History of Pan Congo River as a Strong Geographical Barrier Strong Biogeographical Barrier Species Diversity on the Left Bank of the Congo River Conclusion References The Evolution of Empathy and Its Expression in Bonobos Introduction The Concept of Empathy The Evolution of Empathy Empathy in Bonobos and Other Species Evidence for the Components of Empathy Motor Mimicry and Emotion Contagion Emotion Contagion Consolation Targeted Helping Current and Future Directions Conclusion References Hypotheses for the Evolution of Bonobos: Self-Domestication and Ecological Adaptation Introduction Bonobos and Chimpanzees Compared The Common Ancestor of Gorilla and Pan The Common Ancestor of Bonobos and Chimpanzees Ecological Hypotheses for the Evolution of Bonobos Evaluation of the No Gorillas Hypothesis Putative Evolutionary Consequences of Reduced Scramble Competition Conclusion References Prolonged Sexual Receptivity in Females and Its Impact on the Evolution of Bonobos Introduction Socio-Ecological Hypothesis Related to Female Aggregation Prolonged Sexual Receptivity Hypothesis Influence of Prolonged Sexual Receptivity on Inter-Male Mating Competition and the Social Status of Females Influence of Prolonged Sexual Receptivity and High Social Status on Female Aggregation Influence of High Social Status and Aggregation Patterns on Female Reproductive Strategies Conclusion References Appendix A: List of Researchers Working at Wamba Appendix B: List of Publications on Bonobos and Bongando People Index