This study discusses many variables that may influence the direction of altruism within a family. Significant relationships were found between paternity certainty, conjugal instability, marital residence, cross-cousin marriage preferences, and direction of altruistic behavior. Special emphasis is placed on the importance of the mother's brother.

This study examines cross-cousin marriage preferences from an evolutionary perspective. Results suggest significant associations between cross-cousin marriage preferences and both polygyny and residence.

This study attempts to reconstruct ancestral marriage practices using hunter-gathers' phylogenies based on mitochondrial DNA sequences. Data suggest that arranged marriages and brideprice/bridewealth likely go back at least to the first modern human migrations out of Africa and that early ancestral human societies probably had low levels of polygyny.

This article examines marital residence and sibling coresidence among horticulturalists in the South American lowlands. The authors reject a hypothesis that patrilocality is the defining trait of Amazonian tropical forest culture. Results on horticulturalists are compared with findings on hunter-gatherers: horticulturalists tend to be more uxorilocal. Empirical analysis also suggests that women tend to live with more kin later in life, and in large villages headmen live with more kin than nonheadmen.