The authors explore coalitional play fighting (in which teams of at least two play against each other to achieve a goal) across hunter-gatherer societies, with the theory that play of this type may be a mechanism for assessing strength and utility for future defense or warfare. When played against other communities, they propose coalitional play fighting can also serve to gauge strength of potential allies or formidability of potential enemies. In order to test their theories, they predict that, despite the large energy cost and risk of sports associated with coalitional play fighting, these types of games will be widespread in hunter-gatherer societies. In addition, they predict that of those exhibiting coalitional play fighting, many will play against other communities. In support of their hypotheses, they find that 54% of hunter-gatherer societies examined exhibit coalitional play fighting, of which 81% play against other communities.

Aiming to respond to the question "How has knowledge in forager oral narrative been maintained accurately for dozens of generations?", this study explores the myth transmission rules among forager societies. The first hypothesis anticipates that these rules constrain transmission and contexts similarly across forager societies. The authors suggest that these rules are information technology aids to minimize the chances of errors and loss of information. Related to this, the authors formulate eight hypotheses of what these rules will mandate during myth transmission: 1) skilled storytellers to pass down stories, 2) minimal low-distractions, 3) numerous people 4) multiple generations, 5) measures that identify and correct mistakes, 6) measures that maintain the audience's attention, 7) measures that sanction rule violations, and 8) measures that encourage rule compliance. There is enough evidence to support 7 out of the total of 9 hypotheses. These results show the relevance of studying the rules concerning myth and knowledge transmission across generations.