May 22, 2018 report
Bonobo females found to protect and support a female giving birth
A team of researchers from the University of Pisa and CNRS/Université Claude Bernard Lyon has observed captive female bonobos helping one of their own give birth. In their paper published in the journal Evolution and Human Behavior, Elisa Demuru, Pier Francesco Ferrari and Elisabetta Palagi describe what they witnessed, referring to it as a type of midwifery.
In all of nature, only humans have ever been observed physically assisting one another during delivery of a baby. That has now changed, as the researchers with this new effort report witnessing assisted birth in captive bonobos on three separate occasions.
Bonobos, as the researchers note, are the closest human relatives. And, as has been noted quite often, they are very social—much more so than chimpanzees. The researchers also note that another team of researchers reported seeing females gather around another female as she was giving birth. But the activities reported by the researchers were far more involved. As a female entered labor, they report, other females came over to be near her. As the birth progressed, the surrounding females prevented other males (and humans) from coming near. They also swatted flies away from the exposed genitals.
The behavior was observed at primate parks in The Netherlands and France. The team reports that the assisting females also sniffed at birth fluid and even tried to catch the baby as it was delivered. The researchers note that some of the female midwives had given birth themselves in the past, and thus had some idea of how to help. They also point out that female bonds are always strong among bonobos—they dominate the males in the groups in which they live. Unlike chimpanzees, who go off to be alone when they give birth, bonobos stay with other females, perhaps even expecting to receive help.
The researchers suggest that midwifery might have evolved in a human-chimp-bonobo ancestor, but over time, chimps lost the trait as they became less social. Bonobos have been found to be both highly intelligent, they add, and social, even sharing food. They have also been observed communicating with other species of animals, such as chimps.
Birth attendance has been proposed as a distinguishing feature of humans (Homo sapiens) and it has been linked to the difficulty of the delivery process in our species. Here, we provide the first quantitative study based on video-recordings of the social dynamics around three births in captive bonobos (Pan paniscus), human closest living relative along with the chimpanzee. We show that the general features defining traditional birth attendance in humans can also be identified in bonobos. As in humans, birth in bonobos was a social event, where female attendants provided protection and support to the parturient until the infant was born. Moreover, bystander females helped the parturient during the expulsive phase by performing manual gestures aimed at holding the infant. Our results on bonobos question the traditional view that the "obligatory" need for assistance was the main driving force leading to sociality around birth in our species. Indeed, birth in bonobos is not hindered by physical constraints and the mother is self-sufficient in accomplishing the delivery. Although further studies are needed both in captivity and in the wild, we suggest that the similarities observed between birth attendance in bonobos and humans might be related to the high level of female gregariousness in these species. In our view, the capacity of unrelated females to form strong social bonds and cooperate could have represented the evolutionary pre-requisite for the emergence of human midwifery.
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