Alliance Desire and Homosexual Behavior: The Reason Why There are More Male Homosexual Behavior than Female

Based on the hunter-gatherer lifestyle and the alliance theory, this paper proposes two predictions: 1. Males have more homosexual behavior than females; 2. Grassland males have more homosexual behavior than rainforest male. Combined with these predictions, the paper further hypothesizes that that the need for alliance is the reason why there is more male homosexual behavior than female. To test these predictions, observational studies of four indigenous groups in Africa are proposed. If the observations agree with the predictions, the hypothesis presented in this paper will be supported.