New research has revealed secrets of sex equality among ancient hunter-gatherer communities.

Past studies have found an unusual low level of relatedness in hunter-gatherer groups, which was puzzling because humans tend to rely on family members to help raise offspring, University College London reported. The recent study is the first to show the relationship between sex equality and group composition among hunter-gatherers.

To make these findings, a team of researchers lived among hunter-gatherers in Congo and the Philippines and collected genealogical data on kinship relations as well as camp mobility and residence patterns. This information allowed them to analyze how members of the community were related to one another. They determined the members of these small communities were not related to the majority of their peers.

After collecting this data, the researchers created a computer simulation of the camps' societal compositions. They found that when only on sex had influence over camp assortment (such as kin moving onto the same empty camp together), camp relatedness was high. On the other hand, when both men and women has an influence over these factors, group relatedness dropped significantly.

"While previous researchers have noted the low relatedness of hunter-gatherer bands, our work offers an explanation as to why this pattern emerges. It is not that individuals are not interested in living with kin. Rather, if all individuals seek to live with as many kin as possible, no-one ends up living with many kin at all," first author of the study, Mark Dyble, of UCL Anthropology.

Hunter-gathers are being increasingly influenced by the developed world, but they are the closest example we have of the societal structures of our ancient ancestors.

"Sex equality suggests a scenario where unique human traits such as cooperation with unrelated individuals could have emerged in our evolutionary past," said senior author, Andrea Migliano.

The findings were published in a recent edition of the journal Science.