What explains global variation in sex ratio at birth? To address this question, the authors present the results of their previous research on sex ratio at birth (2003), and additionally introduce new research on the correlations between sex ratio and marriage costs, such as a dowry or brideprice. Using a phylogenetic approach, the authors find that there is no correlation between sex ratio at birth and marriage payments. Analysis is restricted to the Old World.

What explains global variation in sex ratio at birth? To address this question, the authors present the results of their previous research on sex ratio at birth (2003), and additionally introduce new research on the correlations between sex ratio and marriage costs, such as a dowry or brideprice. Using a phylogenetic approach, the authors find that there is no correlation between sex ratio at birth and marriage payments. Analysis is restricted to the Old World.

What explains global variation in sex ratio at birth? To address this question, the authors present the results of their previous research on sex ratio at birth (2003), and additionally introduce new research on the correlations between sex ratio and marriage costs, such as a dowry or brideprice. Using a phylogenetic approach, the authors find that there is no correlation between sex ratio at birth and marriage payments. Analysis is restricted to the Old World.

What explains global variation in sex ratio at birth? To address this question, the authors present the results of their previous research on sex ratio at birth (2003), and additionally introduce new research on the correlations between sex ratio and marriage costs, such as a dowry or brideprice. Using a phylogenetic approach, the authors find that there is no correlation between sex ratio at birth and marriage payments. Analysis is restricted to the Old World.

What explains global variation in sex ratio at birth? To address this question, the authors present the results of their previous research on sex ratio at birth (2003), and additionally introduce new research on the correlations between sex ratio and marriage costs, such as a dowry or brideprice. Using a phylogenetic approach, the authors find that there is no correlation between sex ratio at birth and marriage payments. Analysis is restricted to the Old World.

Evolutionary anthropologists have long emphasized the puzzle of short inter-birth intervals, extended childhoods, and long post-reproductive lives of humans, in particular the problem it poses for raising children. While there is agreement that mothers receive assistance from kin to offset the high costs of raising children, opinion is equivocal as to which kin help and to what extent they help. Here the authors review 45 studies from historical and contemporary natural fertility populations to assess the effects of various types of kin on child survival rates.

Evolutionary anthropologists have long emphasized the puzzle of short inter-birth intervals, extended childhoods, and long post-reproductive lives of humans, in particular the problem it poses for raising children. While there is agreement that mothers receive assistance from kin to offset the high costs of raising children, opinion is equivocal as to which kin help and to what extent they help. Here the authors review 45 studies from historical and contemporary natural fertility populations to assess the effects of various types of kin on child survival rates.

This study presents a phylogenetic approach to the work of Hartung (1982) on the relationship between inheritance and marriage patterns. Results indicate that polygyny is associated with male-biased inheritance.

This article employs a phylogenetic approach to explore traits that might be associated with the cultural transmission of the "witchcraft phenotype" across Bantoid and Bantu ethnolinguistic groups. The authors define the witchcraft phenotype as a set of interlinked traits related to witchcraft beliefs within a society, showing both cross-cultural similarities and regional variations. Despite the widespread historical and geographical presence of witchcraft beliefs, little is known about their evolution and transmission. The article's analysis focuses on the possible ancestral transmission of these traits and their coevolution. The authors suggest that witchcraft phenotypes are often intertwined with beliefs in ancestors, spirits, gods, and other supernatural entities, and like other cultural traits, they can evolve through various mechanisms. Their findings indicate support for phylogenetic transmission of some traits, such as the use of poison to detect witchcraft guilt, but show that other factors such as age and gender do not show evidence of historical transmission.

The ability of adults to digest lactose is common only in populations of European and circum-Mediterranean origin, a distribution thought to be a result of genetic adaptation to drinking milk from domestic livestock. Two additional hypotheses have been proposed to explain the distribution of high lactose digestion capacity: (1) supplemental calcium in high-latitude populations prone to vitamin D deficiency and (2) maintenance of water and electrolytes in the body in highly arid environments. However, these hypotheses are confounded by the shared ancestry of populations whose lactose digestion capability has been tested. Therefore, the authors test all three hypotheses using a phylogenetic comparative method for 62 cultures.