51 pages • 1 hour read
Brian Hare, Vanessa WoodsSurvival of the Friendliest: Understanding Our Origins and Rediscovering Our Common Humanity
Nonfiction | Book | Adult | Published in 2020A modern alternative to SparkNotes and CliffsNotes, SuperSummary offers high-quality Study Guides with detailed chapter summaries and analysis of major themes, characters, and more.
Chapters 2-3Chapter Summaries & Analyses
Chapter 2 Summary: “The Power of Friendliness”
During Stalin’s Great Terror in Russia, 1937-38, the geneticist Dmitry Belyaev pursued his studies despite the regime’s persecution of geneticists. In 1959, he made a groundbreaking experiment in Siberia by domesticating wild foxes. The experiment aimed to reveal whether selection for friendliness alone could lead to domestication traits. Belyaev and his protégée, Lyudmila Trut, divided a population of foxes into two groups. They bred one group based on friendliness toward humans, selecting foxes that approached or showed no fear. The other group was bred randomly, regardless of behavior. Over generations, the friendly foxes exhibited significant changes, both behaviorally and physically. They developed traits common in domesticated animals, such as coat color variations, floppy ears, curled tails, smaller teeth, and different skull shapes. These foxes also became more sociable, bred more frequently, and had higher serotonin levels, a neurotransmitter linked to lower aggression.
This study showed that domesticated traits like physical changes and reduced aggression were by-products of selecting for friendliness. These findings challenged the traditional view that domestication requires direct human intervention in breeding for specific traits. Researchers found genetic links between the foxes’ friendly behavior and certain genes. For example, a gene on chromosome 15 was associated with friendly behavior in foxes and similar regions in dogs. Other genes linked to conditions like Williams syndrome in humans, characterized by hyper-friendliness, were also implicated in the foxes. This genetic evidence reinforced the idea that friendliness was a key factor in domestication across species.
The friendly foxes, despite never being trained to follow human gestures, could understand pointing cues, much like dogs. This ability emerged naturally from the selection for friendliness, suggesting that cognitive skills for cooperative communication could evolve as a by-product of reduced fear and increased sociability. This finding paralleled the behavior of domesticated dogs, which also exhibit advanced social communication skills. These findings highlighted how domestication might have occurred in other species, including early dogs. The hypothesis suggested that the friendliest wolves, attracted to human camps for food, gradually evolved into domesticated dogs. These wolves likely scavenged human waste, which provided ample nutrition. Over generations, these wolves became less fearful and more sociable, eventually developing the capacity to understand and respond to human gestures.
This process of self-domestication might not be unique to dogs. Urban animals today, like coyotes and foxes, show signs of adapting to human environments. These animals often display less fear, greater sociability, and physical changes similar to those observed in domesticated species. The increasing human population in urban areas could drive a new wave of self-domestication, as animals that replace fear with attraction to humans find new ecological niches.
The Belyaev experiment demonstrated that domestication can occur naturally through selection for friendliness, leading to both behavioral and physiological changes. This process provides a model for understanding how domestication has shaped the evolution of various species, including our own relationship with dogs and potentially other animals adapting to human environments. The research underscores the role of sociability and reduced fear in the domestication process, offering insights into the evolution of cooperative behaviors and cognitive skills.
Chapter 3 Summary: “Our Long-Lost Cousins”
Hare and Woods posit that, if dogs and other animals can self-domesticate by becoming friendlier toward humans, perhaps an animal can self-domesticate through interactions with its own species. Bonobos provide an intriguing example. They are as closely related to humans as chimpanzees but exhibit significant differences that align with traits seen in domesticated animals. Bonobos have smaller brains, more juvenile facial features, and display less aggressive and more playful behavior compared to chimpanzees. The authors tell the story of Tai, a nature-reserve chimpanzee, whose life was threatened by aggressive chimpanzees. In the wild, male chimpanzees patrol their territory borders, engaging in brutal fights that can result in serious injuries or deaths. This aggressive behavior extends to their hierarchical social structure, where high-ranking females dominate food sources and lower-ranking females face significant risks.
By contrast, bonobo society operates differently. At Lola ya Bonobo, a sanctuary in the Democratic Republic of Congo, bonobos have been seen to exhibit a friendlier and more cooperative social structure. Females play a dominant role, particularly in protecting their offspring. Male bonobos avoid conflict with infants, understanding that harming a baby would provoke the wrath of the female coalition. This dynamic reduces aggression and fosters a more harmonious environment. Richard Wrangham has proposed that bonobo society evolved to be friendlier due to ecological factors. In bonobo habitats, food resources are more predictable, and the absence of gorillas reduces competition. This environment allows female bonobos to form alliances and support each other, unlike female chimpanzees who compete for resources. Bonobo females prefer less aggressive males, making friendliness a reproductive advantage for males.
Bonobos exhibit several traits associated with self-domestication, similar to those observed in domesticated animals. They are more tolerant and cooperative, even in stressful situations. In experiments, bonobos consistently share food and prefer interacting with strangers over familiar group members, demonstrating a high degree of social tolerance. Physiologically, bonobos have higher levels of serotonin, which reduces aggression and promotes social bonding. Bonobos also outperform chimpanzees in cooperative communication tasks. In tests that require working together to pull a rope and retrieve food, bonobos cooperate immediately and share the rewards fairly. Chimpanzees, however, struggle with cooperation when food is not divided into separate portions. Bonobos’ ability to cooperate and share reflects their overall social tolerance and friendly nature. Bonobos have also shown more flexibility in their vocalizations compared to chimpanzees. They use “peep” sounds in various contexts, and other bonobos interpret these peeps based on situational cues, similar to how humans use language. This vocal flexibility indicates a higher degree of social communication.
These differences between bonobos and chimpanzees highlight the impact of self-domestication on social behavior and cognitive abilities. Bonobos, through natural selection for friendliness, have developed a more cooperative and peaceful society. This stands in stark contrast to the aggressive and hierarchical nature of chimpanzee communities. Understanding bonobos’ self-domestication offers insights into how friendly behaviors can evolve and shape social structures. It challenges the notion that aggression is always advantageous and underscores the potential benefits of cooperation and tolerance. As the friendliest of our primate relatives, bonobos provide a unique perspective on the evolution of social behaviors and the possibilities for creating more harmonious societies.
Chapters 2-3 Analysis
In Chapters 2 and 3, Hare and Woods move into an exploration of the experimental studies that have revealed the processes and implications of domestication, particularly focusing on the groundbreaking work of Dmitry Belyaev. Belyaev’s experiment in domesticating foxes is used as a central element in these chapters, supporting the book’s argument for The Evolutionary Advantages of Friendliness and Cooperation. Belyaev’s hands-on approach provides empirical evidence of how domestication can lead to reduced aggression and enhanced sociability, traits beneficial for both survival and reproduction. The authors underscore the significance of Belyaev’s new method: “Belyaev’s aim was ambitious. Instead of guessing how animals had been domesticated, he decided to domesticate them from scratch and see for himself” (41). His methodology exemplifies a direct observational approach, allowing scientists to document the genetic and behavioral transformations that occur during domestication. Belyaev’s findings revealed that traits like floppy ears, shorter snouts, and increased sociability emerged alongside friendliness, even though these physical traits were never directly selected for. This phenomenon, known as pleiotropy, highlights the interconnected nature of genetic traits and underscores the complexity of evolutionary processes. By laying out and explicating the various steps and findings of Belyaev’s study, Hare and Woods make this seminal study accessible to the general reader, enabling them to understand the scientific foundations on which the author’s arguments rest.
Once establishing this foundation, the authors use these chapters to extensively explore the evolutionary relationship between bonobos, chimpanzees, and humans, emphasizing the unique social behaviors of bonobos. By writing “few animals are friendlier than the bonobo, but bonobos have always been a puzzle” (60), the authors frame their interest in bonobos within their reinterpretation of “survival of the fittest,” which may appear at first to be paradoxical. The authors use bonobos as an example of their main theme, The Evolutionary Advantages of Friendliness and Cooperation. Despite sharing a common ancestor with chimpanzees, bonobos have developed a social structure that prioritizes cooperation over aggression, showcasing the evolutionary benefits of reduced hostility and increased friendliness. The descriptions of chimpanzee behaviors, such as patrolling their territory and engaging in violent conflicts, illustrate the high cost of aggression. The analysis of aggression’s costs, as highlighted in the quote, “It was a clear demonstration of just how costly aggression can be” (64), underscores how violent behavior can limit social connections and reduce overall fitness. This observation supports the argument that sociability and cooperation, traits exemplified by bonobos, offer significant evolutionary advantages. Bonobos’ ability to cooperate, share resources, and maintain social harmony demonstrates the practical benefits of friendliness as an evolutionary strategy.
By showing in detail how Bonobos exhibit less aggressive and more cooperative behaviors than chimpanzees, the authors illuminate The Impact of Social Behavior on Human History and Progress. The authors, in choosing two close ape relatives of humans who display very different behavior, implicitly suggest that humans have a choice about which kind of societies we would like to cultivate: those modeling bonobo behavior or those modeling chimpanzee behavior. Further, the examination of bonobos’ behavior provides insights into Empathy as a Driving Force in Human Interaction. Bonobos’ high degree of social tolerance and their ability to cooperate and share food even with strangers reflect a deep-seated empathy that parallels human social behaviors. This empathy is crucial for forming and maintaining social bonds, which are essential for the survival and success of both individual organisms and their groups. The authors suggest that the friendly and cooperative nature of bonobos can serve as a model for understanding the evolutionary roots of human empathy and social cohesion.
In these chapters, Hare and Woods continue to draw significant historical and scientific references to strengthen their arguments. They emphasize the fact that Charles Darwin was “fascinated by domestication and used it to demonstrate the main principles of his evolutionary theory” (41), bridging historical scientific inquiry with contemporary research. This connection reinforces the validity of their findings and situates their work within a broader scientific context. Their references to Darwin also demonstrate that their work seeks to address common misconceptions about Darwin’s theory of evolution, not to challenge his theory itself.
