What Are Bonobos?

Bonobos, or Pan Paniscus, are one of humanity’s living closest relatives (WWF, 2014). Pan paniscus has many intersting traits, fromt the breadth of their diet to the variety of their modes of locomotion. However, they are most known for their unsual sexual habits. Pan paniscus engage in sexual behavior, including genital and scrotal rubbing, as well as penetrative sex, to resolve tensions surrounding heirarchy and food distribution. They do not discriminate in choosing partners regardless of sex, and it is normal for an individual to cut in on a partner,as well as what we would consider stranger behavior, such as an individual randomly joining individuals engaging in sex, or, as Meredith Small charmingly phrases it, “others join in by randomly

sticking their toes and fingers in moving parts”. As this indicriminant sexual activity is unusual in comproable species, the question arises: What enviromental cirsumstances caused Pan paniscus to evolve this behavior?
Pan paniscus are native to the Congo Basin rainforests of the Democratic Republic of the Congo (WWF 2014).

The WWF describes the Congo Basin as such:

A mosaic of rivers, forests, savannas, swamps and flooded forests, the Congo Basin is teeming with life… There are approximately 10, 000 species of tropical plants in the Congo Basin and 30 percent are unique to the region. Endangered wildlife, including forest elephants, chimpanzees, Pan paniscus, and lowland and mountain gorillas inhabit the lush forests. 400 other species of mammals, 1,000 species of birds and 700 species of fish can also be found here.

The area inhabitited by Pan paniscus does not lack for resources; fruit and small mammals are abundant in the trees and on the ground. Pan paniscus are mostly herbavoious, but are best described as oppotunist omnivores. According to Katherine Lang, author of primatological materials says: “fruit, seeds, sprouts, leaves, flowers, bark, stems, pith, roots, and mushrooms. Though the majority of their diet is fruit (57%), Pan paniscus are also known to consume small mammals, insect larvae, earthworms, honey, eggs, and soil.” Pan paniscus’ clever oppurtunism allows them to sidestep evolutionary niching and leaves them with not want to food resources. Pan paniscus also employ a variety of modes of locomotion, including quadrupedal knuckle walking, modified brachiation and some bipedalism. Pan paniscus spend the majority of their time resting, foraging and feeding, usually at a height

of twenty-five to forty meters above ground (Lang 2010).
The lack of competion for food results in increased sociability among Pan paniscus, says Lang:
Because of the relative richness of their habitat and availability of food sources, there is little constraint on bonobo group size. The result is a decrease in intraspecific feeding competition and heightened sociality, especially between females.
This heightened sociability has insteresting ramifications on group dynamics; for example, a group of loyal, socialable females posses much more power than a solitary female, making it much less likely for any one female to be bullied or attacked by an aggressive male. This gives female Pan paniscus roughly equal social standing in relation to male Pan paniscus, in vast constrast with other comparative ape species.
In addition, this relative social equity removes the threat of danger from sexual activities for females, allowing them to persue recreational sexual activities freely. Because females hold power in numbers, their young offspring are more protected by extension, freeing female Pan paniscus from obligate monogamy. The abundance of resources creates a cascade of behavioral changes the lead to increased casual sexual activities.
The abundance of food allows for another, more unsual behavior: sharing.

Interestingly, Pan paniscus engage in recreational sexual activity the most after finding a particularly large chache of food. It is most likely that Pan paniscus use sexual activity to ‘trade’ a social bond and sexual pleasure for food. Frans de Waal of the Yerkes Regional Primate Research Facility at Emory University explains the concept of sexual activity as social bonding: “Like humans but unlike chimps and most other mammals, Pan paniscus seperate sex from reproduction. They seem to treat sex as a pleasurable activity, and they rely on it as a sort of social glue, to make or break all sorts of relationships.” Meredith Small

elaborates:
One thing sex does for Pan paniscus is decrease tension caused by potential competion, often competion for food. Japanese primatologists observing Pan paniscus in Zaire were the first to discover that when Pan paniscus came across a large fruiting tree or encounter piles of provioned sugar cane, the sight of food triggered a binge of sex. The atmosphere of the sexual free for all is decidedly friendly, and it eventually calms the group down.
The way Pan paniscus treat sexual activity as a social bonding activity is highly unusual amoung comprable mammals. The abudance of resources in the Pan paniscus home enviroment has affected their social behavior in a way so profound that they stand in stark difference when compared to their vastly more aggrssive relatives, so much so that Lyn Heidi, Beca Franks, and Sue Savage-Rumbaugh have found evidence or developing morality, a decidedly human concept:
… [Pan paniscus] are shown to use the symbols “good” and “bad” in appropriate contexts and to co-construct these values with the humans in their environment, indicating that the specific expression of value judgments is cultural. Their developmental use of these symbols parallels studies in children which suggest that conceptual simplicity and internal development may affect the development of moral precursors. These findings support recent research that has found moral precursors in several species of nonhuman primates.
Clearly, the unique selective pressure applied to Pan paniscus has sculpted disctintive sexual behavior. However, the consequences of Pan paniscus sexual bonding has contributed to increased social bonding and the beginnning of culture and the recognition of abstract concepts.
Pan paniscus’ unsual sexual behavior illustrates the far-reaching affects of a slight difference in enviroment. Given an enviroment with less dense resource concentration, Pan paniscus could have had sexual habits more similiar to their agressive chimpanzee cousins. As a consequence of limited resouces, females would either be more selective with sexual partners, putting all her eggs in one basket, as one might put it, or just the opposite, they might engage in sexual activity with every powerful or aggressive male, fearing they might harm another’s offspring.
Either behavior could increase intra or intersexual selection, resulting in more aggression, like the chimpanzees, or display adaptations. However, given that female Pan paniscus would be less likely to bond in a resource-scarce enviroment, taking a significant amount of power away from female individuals as a whole, female Pan paniscus would be in a much more precarious position and may have decreased agency in the realm of sexual behavior. Increased predation may have the same or opposite effect, as it could lead to more vicarious reproduction and comradaric social bonds in the face of danger. Unfortunately, some of these scenarios may become reality as a result of deforestation and poaching.
Pan paniscus have the parlous honor of being one of the few mammals besides humans to engage in sexual behavior recreationally. As unusual as their sexual behavior is, it is quite similiar to our own in surprising ways. In fact, observation of Pan paniscus may enlighten one about human’s own sexual behavior. For example, the Pan paniscus tendency to engage in copious sex after finding resources interestingly parallels an oft repeated adage about women’s fashion; the idea that hemlines rise in favorable economic climates and sink when the economy is in reccession. This is reflected in
American history in other ways; eras of great economic success run tandem to periods of sexual liberation: The roariong twenties, the sex, drugs and rock and roll of the sixties, and the slightly less aggressive surge of sexual imagery in the nineties and early two thousands. Pan paniscus, like humans, also engage in sexual behavior as a form of social bonding not related to reproduction, which is rare behavior amoung mammals. Bonobos, like humans, engage in recreational same sex sexual encounters, although this behavior is far from unique. In summary, pan paniscus’ use of sexual behavior as social lubricant in times of resource gain is enlightening about human’s own sexual behavior in times of success. Perhaps humans are responding to the very same selective pressures that resulted in pan paniscus’ unique habits.
The sexual behaviors of bonobos are the subject of much academic disscussion, and for good reason. The ramifications of pan paniscus’ sexual habits illuminate a wide variety of topics, including the expansive effects small enviromental changes have on selective pressures and humanity’s own unusual sexual behavior. However, the sexual behavior of humans seems more logical in this light: sex is used reacreationally to build bonds to aid in resource sharing and collection. Perhaps humanity’s more primitive bonobo cousins can teach it a lesson in peaceful resource consolidation and productive sexual activity.