Until now, scientists knew that females tend to isolate themselves when they give birth. With the discovery of a new case where a dominant male from a group of wild chimpanzees took and ate a new-born chimpanzee, researchers claim that the protection of the small ones is the basis for this decision.
Scientists Hitonaru Nishie and Michio Nakamura of Kyoto University reported the first observed case in which a small chimpanzee is taken and eaten by an adult male from the same group. Shocking behavior allows researchers to bring new light to both maternal and sexual behavior in wild chimpanzee populations, writes Science Alert.
It is extremely difficult for researchers to make such observations, precisely because females isolate themselves at the time of their birth. However, Japanese scholars have been fortunate when a female from the group gave birth without leaving the group.
The woman, called Devota, was part of that group in the last two years until the time of her birth on a rainy day in December 2014; the scientists did not notice any signs of pregnancy, so the event was a surprise.
“The whole incident happened very quickly”
Unfortunately, the event turned from surprise to shock when Darwin, a dominant male from the group, took the newborn and left so quickly that Devota had no time to touch it.
“The whole incident happened very quickly; so we cannot confirm whether the new-born was dead or alive and we do not know it’s sex”, the team said in a recent study published in The Amercian Journal of Physical Anthropology.
After 45 minutes, the researchers located the male who had already begun to eat the newborn’s feet. In the next hour, they also noticed other males who ate the remaining parts of Darwin’s dinner.
The team witnessed this event during the study of a large group of chimpanzees in the Mahale Mountains near Lake Tanganyika in Tanzania. Called simply “M Group”, it has been pursued since 1968 until today.
Also, this behavior is encountered in many primates and occurs because of competition – killing a fetus that is not theirs means that the female will be available sooner for another mating attempt, increasing the chimpanzee’s chances of having new babies with her (this but it does not explain why they have to eat it).
However, cases of cannibalism indicate to researchers the possible reason that causes females to hide when they give birth. It is possible for Devota that she was not experienced enough to hide.