Are Bonobos Cuckold or Jealous?
Bonobos are an intriguing species of great ape known for their peaceful, matriarchal societies and frequent sexual interactions. Unlike chimpanzees and many other primates that show clear male dominance, jealousy, and aggression over mating rights, bonobo behavior seems to embrace more fluid relationships and sexuality. This has led to questions about whether bonobos truly experience concepts like cuckoldry that underpin possessiveness and jealousy in other species.
What is Cuckoldry and Why Does it Matter?
In evolutionary biology, the concept of cuckoldry refers to scenarios where a female secretly mates with another male, causing her mate to unknowingly invest parental effort in offspring that are not genetically his. This is not in the evolutionary interests of the cuckolded male. As such, males of many species have evolved intense jealousy, mate guarding, and aggression around mating rights to avoid cuckoldry scenarios.
However, the bonobo social structure does not neatly fit assumptions around mating competition and paternity certainty. To understand why, we must first examine some of their unique traits.
Key Traits of Bonobo Behavior and Sexuality
Bonobos display some striking behaviors that set them apart:
Female coalitions and hierarchy: Unlike other great apes, bonobo societies are centered around strong lifelong bonds between unrelated females rather than male dominance. Females form tight-knit groups that allow them to successfully compete with males for food and leverage sex to diffuse tension.
Frequent sex between all combinations: Bonobos engage in significantly more sex in more partner combinations (male-female, female-female, male-male) than chimps and humans. Sex serves social functions like greeting, reconciliation, exchange for food, and bonding.
Concealed ovulation: Unlike chimps, bonobo females show no visible signs of fertility, meaning males cannot easily determine the probability of paternity. This may reduce direct mating competition.
Extended maternal care: Bonobo offspring rely on mothers for years, not just infancy. With no certainty which male sired an infant, extended maternal care may allow time for other social bonds to deepen with community members regardless of paternity.
So in contrast to assumptions around mating competition, bonobos exhibit more indeterminate parentage, fluid relationships, and shared community care of the young. How do these traits influence cuckoldry and jealousy?
Is Cuckoldry Relevant to Promiscuous Bonobos?
Given the above traits, the concept of cuckoldry loses some meaning in bonobo societies.
With frequent sex among multiple partners, paternity certainty is low for all males. No single male can reliably guard a female as his exclusive mate. Further, there are no obvious signs of fertility, so males cannot focus mating efforts only on likely fertile periods.
In species where cuckoldry matters, males target aggression toward female mates assumed sexual rivals. But in bonobos, females bond together in powerful alliances, likely limiting potential male harassment over fidelity.
Importantly, while one bonobo male may not sire all his mates' offspring, the various offspring still dwell within his community. The children rely on extended maternal care but also eventually interact with and may form bonds with various adults in the group.
So unlike a cuckolded male of another species that only invests in another male's genes, bonobo males still potentially contribute to the future success of their community's youth - some of which may even carry their genes.
Do Bonobos Experience Sexual Jealousy?
Given this open mating structure centered around female solidarity and community care, researchers have questioned whether bonobos even experience jealousy like humans or other primates.
Some observations show bonobos exhibiting possessive behaviors:
- Males sometimes follow mating pairs and attempt to disrupt mounting. This may indicate mating competition.
- High-ranking females occasionally chase others away from esteemed males. This suggests some priority access.
- Mothers with dependent offspring have been seen interfering with other females approaching their male allies. This hints at paternity assurance in offspring care.
However, while bonobos show some capability for possessiveness, these incidents seem relatively mild compared to extreme mate guarding and lethal violence seen in chimps.
Rather than individual sexual jealousy, primatologists Martin Surbeck and Gottfried Hohmann argue bonobos exhibit “social tolerance” around mating rights. As long as status and solidarity among female circles remain intact, the community accepts fluid partnerships.
Evolutionary Roots of Bonobo Behavior
How did such distinct bonobo patterns develop when other great apes show much higher male dominance, infanticide, estrous signals, and mate competition?
Some evidence suggests bonobo anatomy itself limits lethal violence. Their skulls and muscles contain less mass compared to chimps, particularly in jaws and forearms used for killing blows. This physical constraint may have necessitated more cooperative social norms.
Additionally, some theories point to bonobo-feeding habitats centered in riparian forests as shaping their social foundations. The riverbank vegetation offered a more consistent bounty compared to chimpanzee habitats, allowing bonobo females and offspring to subsist without depending so heavily on male hunting provisioning. This abundance enabled females to bond together and exert greater social leverage.
Other experts think skeletal studies indicating year-round mating patterns in ancestral bonobos better allowed both sexes to contribute to offspring care. This may have required more collaborative child-rearing networks before fixed-pair bonding.
The Bonobo Example Challenges Assumptions of Possession and Paternity
What we interpret as cuckoldry stems from assumptions around mating competition in male-dominated societies. The bonobo case reminds us that social incentives around fidelity and parental investment manifest differently depending on the species’ evolutionary trajectory.
Rather than strict individual sexual jealousy, bonobos operate via a more collective social tolerance. Their adaptive strengths lie in gender collaboration, broad resource access, and shared community bonds balancing individual genetic uncertainties.
In environments where food was plentiful enough to sustain cooperation, female solidarity strong enough to temper violence, and paternity certainty diluted across the community, strict sexual possessiveness may not have improved individual or group fitness.
Of course, bonobos still compete in ways to further their status and genes, just not via aggressive monopoly over mates. As the University of Michigan evolutionary biologist Thaddeus Tarpey concludes, “Bonobos reveal the flexibility and context sensitivity of so-called ‘fundamental’ behaviors often assumed to be species-wide universals.”
Ultimately, the bonobo societies offer a glimpse at how intelligent social mammals can construct alternative norms around key evolutionary drivers like sex, parenting, resources, and violence. Observing the dynamics within these great ape cousins helps us reflect on the diversity of possible social contracts beyond the traditional models of human culture.
References:
- Wikipedia - Bonobo:
- The bonobo (Pan paniscus) is an endangered great ape found in the Congo Basin of the Democratic Republic of the Congo (DRC), Central Africa.
- They are distinguished from common chimpanzees by their relatively long limbs, pinker lips, darker faces, and parted, longer hair on their heads.
- Bonobos are predominantly frugivorous and inhabit primary and secondary forests.
- They are the closest extant relative to humans, sharing a common ancestor around 8 million years ago.
- Estimated population ranges from 29,500 to 50,000 individuals
- SpringerLink - Bonobo Sexuality:
- This article explores aspects of bonobo sexuality.
- Bonobos exhibit unique sexual behaviors, including frequent copulation, same-sex interactions, and using sex for social bonding.
- Their sexual openness contributes to their social structure and conflict resolution
- Britannica - Bonobo:
- The bonobo (Pan paniscus) was initially regarded as a subspecies of the chimpanzee (Pan troglodytes).
- Found only in lowland rainforests along the south bank of the Congo River in the Democratic Republic of the Congo.
- Bonobos exhibit distinct behaviors, such as female dominance, strong social bonds, and resolving conflicts through sexual interactions
