Considerable variation has been observed in allomaternal nursing (breast-feeding by individuals other than mothers) behavior across contemporary foraging populations: while relatively common in some populations, it is rare or absent among others. Here the authors examine data on allomaternal nursing from 12 previous studies of foraging societies and utilize a worldwide sample of 104 cultures to assess global variation in allomaternal nursing.

Considerable variation has been observed in allomaternal nursing (breast-feeding by individuals other than mothers) behavior across contemporary foraging populations: while relatively common in some populations, it is rare or absent among others. Here the authors examine data on allomaternal nursing from 12 previous studies of foraging societies and utilize a worldwide sample of 104 cultures to assess global variation in allomaternal nursing.

Considerable variation has been observed in allomaternal nursing (breast-feeding by individuals other than mothers) behavior across contemporary foraging populations: while relatively common in some populations, it is rare or absent among others. Here the authors examine data on allomaternal nursing from 12 previous studies of foraging societies and utilize a worldwide sample of 104 cultures to assess global variation in allomaternal nursing.

Considerable variation has been observed in allomaternal nursing (breast-feeding by individuals other than mothers) behavior across contemporary foraging populations: while relatively common in some populations, it is rare or absent among others. Here the authors examine data on allomaternal nursing from 12 previous studies of foraging societies and utilize a worldwide sample of 104 cultures to assess global variation in allomaternal nursing.

Considerable variation has been observed in allomaternal nursing (breast-feeding by individuals other than mothers) behavior across contemporary foraging populations: while relatively common in some populations, it is rare or absent among others. Here the authors examine data on allomaternal nursing from 12 previous studies of foraging societies and utilize a worldwide sample of 104 cultures to assess global variation in allomaternal nursing.

This study asserts that premastication (the pre-chewing of food for infant feeding) has existed as a cross cultural human universal stemming from the post natal immaturity of infant development and their need to have nutritional supplements to breast milk before they develop the molars necessary to consume an adult diet. Hypotheses are informally tested by sampling 119 cultures from the eHRAf database and looking for frequency of premastication occurrence. About one-third with information on infant feeding mention pre-mastication.

Social scientists are equivocal as to the importance of teaching (as contrasted with other forms of learning) in traditional societies. While many cultural anthropologists have downplayed the importance of teaching, cognitive psychologists often argue that teaching is a salient human universal. Here the authors investigate cultural transmission among 23 hunter-gatherer populations to explore the relative importance of teaching among foragers.

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.

Social scientists are equivocal as to the importance of teaching (as contrasted with other forms of learning) in traditional societies. While many cultural anthropologists have downplayed the importance of teaching, cognitive psychologists often argue that teaching is a salient human universal. Here the authors investigate cultural transmission among 23 hunter-gatherer populations to explore the relative importance of teaching among foragers.

Social scientists are equivocal as to the importance of teaching (as contrasted with other forms of learning) in traditional societies. While many cultural anthropologists have downplayed the importance of teaching, cognitive psychologists often argue that teaching is a salient human universal. Here the authors investigate cultural transmission among 23 hunter-gatherer populations to explore the relative importance of teaching among foragers.