The study builds on a previous study with the Maasai suggesting that matrilineal descent will close that gap of competitive behavior between men and women. The author conducted a lab experiment consisting of 614 individuals representative of 27 ethnic groups in the Democratic Republic of the Congo. In the experiment, the participants completed a timed matching game. First, they played alone with the goal to complete 5 games within 5 minutes to win money. Next, they competed against an undisclosed opponent to complete the most games and to keep all of the winnings. Finally, the participants were able to choose which pay they preferred based solely on the results from the first round. This was designed to reflect competition preference and results indicated that women were less likely to engage in competition regardless of kinship system.

Lowes and Nunn test the theory that the transatlantic and Indian Ocean slave trades of the thirteenth to nineteenth centuries prompted a shift towards matrilineal kinship systems throughout sub-Saharan Africa. Controlling for ecological variables commonly thought to affect kinship structure (including ruggedness of terrain, suitability for agriculture, etc.), the authors find a significant correlation between the number of people enslaved from a given ethnic group, and the tendency of that group towards a matrilineal kinship system. Polygyny was also identified as a statistically significant characteristic of communities most impacted by the slave trade.