Researchers found that immature male chimps love to play, as much as their young human male counterparts.
Studies about sex differences in young mammals mostly focus on behaviors associated with social interactions when they grow into adults. Little is known or researched about potential sex variations involved in tool usage and skills as these species prepare for adulthood
The study involved Chimpanzees (Pan troglodytes schweinfurthii) in Uganda and bonobos (Pan paniscus) in Wamba, Congo, which are human's closest living relatives, with a common ancestor some one million years back. The chimps were recognized to use tools in a variety of setting such as social interactions foraging and self-maintenance. The bonobos, on the other hand, were said to use very few objects and even none for feeding purposes.
The goal of the study is to know if sex differences in terms of object manipulation are being employed by immature chimps and bonobos as preparation for tool use later in life.
For three months, the species were observed in the wild, including the duration with which they fiddle with objects in the forest including leaves and sticks.
The findings of the study showed that the chimps exhibited sex differences in object manipulation, while the bonobos did not.
The researchers found that immature male chimps manipulated the objects more compared to their female counterparts. This discovery is said to refute the "preparation for tool use" theory made at the beginning of the study. Nonetheless, the female chimps showed more diverse ways of manipulating materials compared to the males, which manipulations appeared play-based.
Dr. Kathelijne Koops, one of the study authors, recalled that at first, they were puzzled as to what was happening. When they looked closely, it appeared that the immature male chimps used the objects as toys - fiddling, chasing and getting all messy with it. She added that in females, the manipulation was more of objective-driven.
The given similarity between chimps and humans is something notable. Both little human boys and immature chimps exhibit behaviors that involve throwing and hitting objects. These ways of object manipulation may be associated with preparation for tool use in both species such that chimps do so as defense preparation and humans as weapon adaptation.
Koops added that with the evolutionary associations between humans, chimpanzees and bonobos, experts are given information about the sex differences among species in in terms of the so-called "preparation for tool use." These could help the experts understand the functions involved in the controversial sex differences among human children.
The research is published in the journal PLOS ONE on Wednesday, Oct. 7.
Photo: Eric Kilby | Flickr
