This dissertation takes a sociobiological approach to examining altruistic behavior in humans. Hypotheses regarding the relationship between individuals and altruistic behaviors are tested and supported by cross-cultural analysis.

The present research investigates food sharing and labor sharing practices of 98 nonindustrial societies. The aims are to: 1) document the frequency and scope of sharing, and 2) test the theory that greater sharing is adaptive in societies subject to more resource stress (including natural hazards).

The present research investigates food sharing and labor sharing practices of 98 nonindustrial societies. The aims are to: 1) document the frequency and scope of sharing, and 2) test the theory that greater sharing is adaptive in societies subject to more resource stress (including natural hazards).

The present research investigates food sharing and labor sharing practices of 98 nonindustrial societies. The aims are to: 1) document the frequency and scope of sharing, and 2) test the theory that greater sharing is adaptive in societies subject to more resource stress (including natural hazards).

This study examined the relationship between market integration and generalized prosocial behavior. The authors review theory suggesting that market integration fosters cooperation and fairness in dealing with strangers, and they investigate whether child training for generosity, honesty, and trust are associated with level of market integration among societies in the Standard Cross-Cultural Sample. Results do not indicate an association.

This article takes an evolutionary approach to understanding the patterns of characterization in folktales cross-culturally. Results indicate that literature shares several common themes cross-culturally, including mate selection and kin directed altruism.

"The kin selection hypothesis posits that male androphilia evolved because androphilic males invest more in kin, thereby enhancing inclusive fitness." However, increased kin-directed altruism has only been seen in societies that exhibit transgendered male androphilia. To test the validity of the kin selection hypothesis for male androphilia, the authors examine the relationship between ancestral sociocultural conditions, access to kin, and societal reactions to homosexuality and the expression of male androphilia as transgendered or non-transgendered. They find that ancestral sociocultural conditions and bilateral and double descent systems were more common in transgendered than non-transgendered societies.

Researchers sampled 48 societies cross-culturally to study the genetic survival of male homosexual preference, which is argued to be deleterious in nature due to its fertility costs. The researchers test for a sexually antagonistic factor that would produce a pleotropic advantage, such as male homosexual preference increasing the reproduction of sisters. Utilizing theoretical models, researchers assert that the survival of male homosexual preference is a result of the positive association between social stratification and discriminate female hypergyny due to selection for attractiveness in females.

The researcher looks for empirical evidence of natural selection as an explanation for worldwide variation in novelty-seeking behavior. Examining the relationship between variability in frequency of the DRD4 exon III 7-repeat allele variant (a variant theorized to stifle dopamine reception and thus encourage compensatory novelty-seeking behavior) and migratory distance from prehistoric humans' origin point in East Africa yields a positive correlation. After controlling for various biogeographic indicators, the researcher theorizes that presence of the DRD4 exon III 7-repeat variant provided an exploratory urge and evolutionary advantage to hunter-gatherers and pastoralists who migrated into unfamiliar environments.

The researcher looks for empirical evidence of natural selection as an explanation for worldwide variation in novelty-seeking behavior. Examining the relationship between variability in frequency of the DRD4 exon III 7-repeat allele variant (a variant theorized to stifle dopamine reception and thus encourage compensatory novelty-seeking behavior) and migratory distance from prehistoric humans' origin point in East Africa yields a positive correlation. After controlling for various biogeographic indicators, the researcher theorizes that presence of the DRD4 exon III 7-repeat variant provided an exploratory urge and evolutionary advantage to hunter-gatherers and pastoralists who migrated into unfamiliar environments.