The literature on human mate preferences is vast but most data come from studies on college students in complex societies, who represent a thin slice of cultural variation in an evolutionarily novel environment. Here, I present data on the mate preferences of men and women in a society of hunter-gatherers, the Hadza of Tanzania. Hadza men value fertility in a mate more than women do, and women value intelligence more than men do. Women place great importance on men’s foraging, and (...) both sexes rate character as important. Unlike college students, Hadza men place considerable importance on women being hard-working, and Hadza women cite looks about as often as men do. (shrink)

Strong reciprocity is an effective way to promote cooperation. This is especially true when one not only cooperates with cooperators and defects on defectors (second-party punishment) but even punishes those who defect on others (third-party, “altruistic” punishment). Some suggest we humans have a taste for such altruistic punishment and that this was important in the evolution of human cooperation. To assess this we need to look across a wide range of cultures. As part of a cross-cultural project, I played three (...) experimental economics games with the Hadza, who are hunter-gatherers in Tanzania. The Hadza frequently engaged in second-party punishment but they rarely engaged in third-party punishment. Other small-scale societies engaged in less third-party punishment as well. I suggest third-party punishment only became more important in large, complex societies to solve more pressing collective-action problems. (shrink)

Using questionnaire data completed by 170 men, we examine variation in paternal investment in relation to the trade-off between mating and parenting. We found that as men’s self-perceived mate value increases, so does their mating effort, and in turn, as mating effort increases, paternal investment decreases. This study also simultaneously examined the influence on parental investment of men’s mating effort, men’s perception of their mates’ fidelity, and their perceived resemblance to their offspring. All predicted investment. The predictors of investment are (...) also tested independently for men who are still in a relationship with the mother of their children and those that are separated from her. Finally we examine how self-perceived mate value affects how men respond to variation in paternity confidence. Men with a self-perceived low mate value were less likely to respond to lowered mate fidelity by reducing their parental investment compared with men with a self-perceived high mate value. (shrink)

Cooperative child care among humans, where individuals other than the biological mother (allomothers) provide care, may increase a mother’s fertility and the survivorship of her children. Although the potential benefits to the mother are clear, the motivations for allomothers to provide care are less clear. Here, we evaluate the kin selection allomothering hypothesis using observations on Hadza hunter-gatherers collected in ten camps over 17 months. Our results indicate that related allomothers spend the largest percentage of time holding children. The higher (...) the degree of relatedness among kin, the more time they spend holding, supporting the hypothesis of nepotism as the strongest motivation for providing allomaternal care. Unrelated helpers of all ages also provide a substantial amount of investment, which may be motivated by learning to mother, reciprocity, or coercion. (shrink)

Humans have a much longer juvenile period (weaning to first reproduction, 14 or more years) than their closest relatives (chimpanzees, 8 years). Three explanations are prominent in the literature. (a) Humans need the extra time to learn their complex subsistence techniques. (b) Among mammals, since length of the juvenile period bears a constant relationship to adult lifespan, the human juvenile period is just as expected. We therefore only need to explain the elongated adult lifespan, which can be explained by the (...) opportunity for older individuals to increase their fitness by providing for grandchildren. (c) The recent model by Kaplan and colleagues suggests that longevity and investment in "embodied capital" will coevolve, and that the need to learn subsistence technology contributed to selection for our extended lifespan.We report experiments designed to test the first explanation: human subsistence technology takes many years to learn, and spending more time learning it gives reproductive benefits that outweight lost time. Taking away some of this time should lead to deficits in efficiency. We paid Hadza foragers to participate in tests of important subsistence skills. We compared efficiency of males and females at digging tubers. They differ greatly in time spent practicing digging but show no difference in efficiency. Children who lost "bush experience" by spending years in boarding school performed no worse at digging tubers or target archery than those who had spent their entire lives in the bush. Climbing baobab trees, an important and dangerous skill, showed no change with age among those who attempted it. We could show no effects of practice time.These findings do not support what we label "the practice theory," but we discuss ways in which the theory could be defended; for example, some as-yet-untested skill may be greatly impaired by loss of a few years of the juvenile period. Our data also show that it is not safe to assume that increases in skill with age are entirely due to learning or practice; they may instead be due to increases in size and strength. (shrink)

We present a cross-cultural analysis showing that the presence of an active or moral High God in societies varies generally along a continuum from lesser to greater technological complexity and subsistence productivity. Foragers are least likely to have High Gods. Horticulturalists and agriculturalists are more likely. Pastoralists are most likely, though they are less easily positioned along the productivity continuum. We suggest that belief in moral High Gods was fostered by emerging leaders in societies dependent on resources that were difficult (...) to manage and defend without group cooperation. These leaders used the concept of a supernatural moral enforcer to manipulate others into cooperating, which resulted in greater productivity. Reproductive success would accrue most to such leaders, but the average reproductive success of all individuals in the society would also increase with greater productivity. Supernatural enforcement of moral codes maintained social cohesion and allowed for further population growth, giving one society an advantage in competition with others. (shrink)

Among hunter-gatherers, the sharing of male and female foods is often assumed to result in virtually the same diet for males and females. Although food sharing is widespread among the hunting and gathering Hadza of Tanzania, women were observed eating significantly more tubers than men. This study investigates the relationship between patterns of dental wear, diet, and extramasticatory use of teeth among the Hadza. Casts of the upper dentitions were made from molds taken from 126 adults and scored according to (...) the Murphy dental attrition scoring system. Females had significantly greater anterior occlusal wear than males when we controlled for age. Males exhibited greater asymmetry in wear, with greater wear on the left side in canines, first premolars, and first molars. We suggest that these sex differences in wear patterns reflect the differences seen in the diet, as well as in the use of teeth as tools. (shrink)

We use data collected among Hadza hunter-gatherers between 2005 and 2009 to examine hypotheses about the causes and consequences of men’s foraging and food sharing. We find that Hadza men foraged for a range of food types, including fruit, honey, small animals, and large game. Large game were shared not like common goods, but in ways that significantly advantaged producers’ households. Food sharing and consumption data show that men channeled the foods they produced to their wives, children, and their consanguineal (...) and affinal kin living in other households. On average, single men brought food to camp on 28% of days, married men without children at home on 31% of days, and married men with children at home on 42% of days. Married men brought fruit, the least widely shared resource, to camp significantly more often than single men. A model of the relationship between hunting success and household food consumption indicates that the best hunters provided 3–4 times the amount of food to their families than median or poor hunters. These new data fill important gaps in our knowledge of the subsistence economy of the Hadza and uphold predictions derived from the household and kin provisioning hypotheses. Key evidence and assumptions backing prior claims that Hadza hunting is largely a form of status competition were not replicated in our study. In light of this, family provisioning is a more viable explanation for why good hunters are preferred as husbands and have higher fertility than others. (shrink)

When we have asked Hadza whether married couples should live with the family of the wife (uxorilocally) or the family of the husband (virilocally), we are often told that young couples should spend the first years of a marriage living with the wife’s family, and then later, after a few children have been born, the couple has more freedom—they can continue to reside with the wife’s kin, or else they could join the husband’s kin, or perhaps live in a camp (...) where there are no close kin. In this paper, we address why shifts in kin coresidence patterns may arise in the later years of a marriage, after the birth of children. To do so, we model the inclusive fitness costs that wives might experience from leaving their own kin and joining their husband’s kin as a function of the number of children in their nuclear family. Our model suggests that such shifts should become less costly to wives as their families grow. This simple model may help explain some of the dynamics of postmarital residence among the Hadza and offer insight into the dynamics of multilocal residence, the most prevalent form of postmarital residence among foragers. (shrink)

Researchers from across the social sciences have found consistent deviations from the predictions of the canonical model of self-interest in hundreds of experiments from around the world. This research, however, cannot determine whether the uniformity results from universal patterns of human behavior or from the limited cultural variation available among the university students used in virtually all prior experimental work. To address this, we undertook a cross-cultural study of behavior in ultimatum, public goods, and dictator games in a range of (...) small-scale societies exhibiting a wide variety of economic and cultural conditions. We found, first, that the canonical model – based on self-interest – fails in all of the societies studied. Second, our data reveal substantially more behavioral variability across social groups than has been found in previous research. Third, group-level differences in economic organization and the structure of social interactions explain a substantial portion of the behavioral variation across societies: the higher the degree of market integration and the higher the payoffs to cooperation in everyday life, the greater the level of prosociality expressed in experimental games. Fourth, the available individual-level economic and demographic variables do not consistently explain game behavior, either within or across groups. Fifth, in many cases experimental play appears to reflect the common interactional patterns of everyday life. Key Words: altruism; cooperation; cross-cultural research; experimental economics; game theory; ultimatum game; public goods game; self-interest. (shrink)

We would like to thank the commentators for their generous comments, valuable insights and helpful suggestions. We begin this response by discussing the selfishness axiom and the importance of the preferences, beliefs, and constraints framework as a way of modeling some of the proximate influences on human behavior. Next, we broaden the discussion to ultimate-level (that is evolutionary) explanations, where we review and clarify gene-culture coevolutionary theory, and then tackle the possibility that evolutionary approaches that exclude culture might be sufficient (...) to explain the data. Finally, we consider various methodological and epistemological concerns expressed by our commentators. (shrink)

Human population growth must end, and the sooner the better, for both nature and a humanity that pursues boundlessly increasing affluence. Poisoning of organisms and massive extinctions result, exacerbated by population momentum. Infliction of pain and death largely for trivial reasons constitutes the ignoble dénouement of our history. Reducing human numbers would be only one fitting response to recognition of this situation. Reliance on voluntary socio-economic reforms, including even the empowennent of women, appears unlikely to lead to below-replacement-level fertility, since (...) families on average still elect to have more than two children. Discussed are three reasons for thinking that coercive measures could help to engender a decreasing human population without negating preferable voluntary efforts to the same end. Hence some coercion to reduce fertility is justifiable. (shrink)

The task of transforming Durkheim's sociological perspective into an explanation of poverty in rural areas carries a triple handicap: Durkheim was not concerned with material well-being, he did not conceptualize structures of inequality, and his explanation of the division of labor was flawed. His late book on religion, however, contains an explanation of institutional innovation which offers a new starting point for understanding formal dimensions such as differentiation and pluralism, and these in turn as they are related to poverty. When (...) these dimensions are combined with technical organization, differences in welfare can be explained. When the summary formula for this combination of structure and technology is compared with those for Marxist and conventional economic explanations, the result is a dramatic contrast between the two materialist theories and a true sociological position. (shrink)

While most studies of low-carbon transitions focus on green niche-innovations, this paper shifts attention to the resistance by incumbent regime actors to fundamental change. Drawing on insights from political economy, the paper introduces politics and power into the multi-level perspective. Instrumental, discursive, material and institutional forms of power and resistance are distinguished and illustrated with examples from the UK electricity system. The paper concludes that the resistance and resilience of coal, gas and nuclear production regimes currently negates the benefits from (...) increasing renewables deployment. It further suggests that policymakers and many transition-scholars have too high hopes that ‘green’ innovation will be sufficient to bring about low-carbon transitions. Future agendas in research and policy should therefore pay much more attention to the destabilization and decline of existing fossil fuel regimes. (shrink)

Brain function depends on the cooperation between highly specialized cells. Neurons generate electrical signals and glial cells provide structural and metabolic support. Here, I propose a new kind of job‐sharing between neurons and astrocytes. Recent studies on primary cultures of highly purified neurons from the rodent central nervous system (CNS) suggest that, during development, neurons reduce or even abandon cholesterol synthesis to save energy and import cholesterol from astrocytes via lipoproteins. The cholesterol shuttle may be restricted to compartments distant from (...) the soma including synapses and may be regulated by electrical activity. Testing these hypotheses will help to improve our still insufficient understanding of brain cholesterol metabolism and its role in neurodegeneration. BioEssays 25:72–78, 2003. © 2002 Wiley Periodicals, Inc. (shrink)

This paper considers a problem that arises for free will defenses when considering the nature of God's own will. If God is perfectly good and performs praiseworthy actions, but is unable to do evil, then why must humans have the ability to do evil in order to perform such actions? This problem has been addressed by Theodore Guleserian, but at the expense of denying God's essential goodness. I examine and critique his argument and provide a solution to the initial problem (...) that does not require abandoning God's essential goodness. (shrink)

The aim of this study was to explore stakeholder perceptions of the contribution of an Automatic Milking System (AMS) to sustainable development of organic dairy production in Denmark and the Netherlands. In addition, reasons for the current difference in AMS use on organic dairy farms between both countries were explored. To answer above mentioned aims, farmers and advisors in both countries were interviewed using a focus group approach. Questions of the interviews were based on a literature review on sustainability issues (...) affected by introduction of AMS. Participants expressed no moral problems regarding AMS use. They, however, pointed out uncertainty about the economic gain, difficulties with grazing, adaptation problems to technology, and image problems towards consumers. The latter results from a reduction in grazing time affecting both animal welfare and product quality. The participants did not recognize eutrophication, as result of high stocking density on farmstead lots, as a problem caused by AMS. The milk quality problem related to AMS use, although acknowledged as crucial towards consumers, was not prioritized very highly, especially not by the farmers in both countries. All groups were, however, unanimous in their perception of how important image was as far as the consumers are concerned. The perception analysis revealed that Dutch participants were more concerned about the economic payoff of AMS use, and showed more reluctance towards enlargement than Danish ones. In addition, they acknowledged the small-scale naturalness of organic production. These differences in perception could possibly explain observed differences in AMS use in organic dairy production between Denmark and the Netherlands. (shrink)

I begin with a distinction between narrow and broad defenses to the logical problem of evil. The former is simply an attempt to show that God and evil are not logically incompat-ible whereas the latter attempts the same, but only by appealing to beliefs one takes to be true in the actual world. I then argue that while recent accounts of original sin may be consistent with a broad defense, they are also logically incoherent. After considering potential replies, I conclude (...) by proposing an account of original sin that is both logically coherent and consistent with a broad defense. (shrink)

This work has been selected by scholars as being culturally important and is part of the knowledge base of civilization as we know it. This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work. Scholars believe, and we concur, that this work is important enough to be (...) preserved, reproduced, and made generally available to the public. To ensure a quality reading experience, this work has been proofread and republished using a format that seamlessly blends the original graphical elements with text in an easy-to-read typeface. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant. (shrink)

The idea of the orderly output constraint is compared with recent findings about the representation of vowels in the auditory cortex of an animal model for human speech sound processing (Ohl & Scheich 1997). The comparison allows a critical consideration of the idea of neuronal “feature extractors,” which is of relevance to the noninvariance problem in speech perception.

In a previous issue of this journal Michael Veber argued that God could not answer certain prayers because doing so would be immoral. In this article I attempt to demonstrate that Veber’s argument is simply the logical problem of evil applied to a possible world. Because of this, his argument is susceptible to a Plantinga-style defense.

This article critically discusses the state of STS, expressing feelings of discontent regarding four aspects: policy relevance, conceptual language, too much focus on complexity, theoretical styles. Middle range theory is proposed as an alternative, promising avenue. Middle range theories focus on delimited topics, make explicit efforts to combine concepts, and search for abstracted patterns and explanatory mechanisms. The article presents achievements in that direction for technology dynamics, particularly with regard to the role of expectations, niche theory and radical innovation, and (...) the multi-level perspective on sociotechnical transitions. (shrink)

The aim of this paper is to discuss a key question in the history and philosophy of medicine, namely how scholars should treat the practices and experimental hypotheses of modern life science laboratories. The paper seeks to introduce some prominent historiographical methods and theoretical approaches associated with biomedical research. Although medical scientists need no convincing that experimentation has a significant function in their laboratory work, historians, philosophers, and sociologists long neglected its importance when examining changes in medical theories or progress (...) in scientific knowledge. The reason appears to have been the academic influence of the then dominant tradition in the history of ideas, but was also due to a misconception of what could usefully be termed the view on “historical ontology.” During the last two decades, there have been many books and research articles that have turned towards the subject, so that the study of experimental practice has become a major trend in the contemporary history and philosophy of medicine. A closer look at the issue of laboratory research shows that concepts in medicine and the life sciences cannot be understood as historically constant, free-standing ideas, but have to be regarded as dependent on local research settings. They often carry particular “social memories” with them and thus acquire important ethical implications. (shrink)

The aim of this paper is to discuss a key question in the history and philosophy of medicine, namely how scholars should treat the practices and experimental hypotheses of modern life science laboratories. The paper seeks to introduce some prominent historiographical methods and theoretical approaches associated with biomedical research. Although medical scientists need no convincing that experimentation has a significant function in their laboratory work, historians, philosophers, and sociologists long neglected its importance when examining changes in medical theories or progress (...) in scientific knowledge. The reason appears to have been the academic influence of the then dominant tradition in the history of ideas, but was also due to a misconception of what could usefully be termed the view on “historical ontology.” During the last two decades, there have been many books and research articles that have turned towards the subject, so that the study of experimental practice has become a major trend in the contemporary history and philosophy of medicine. A closer look at the issue of laboratory research shows that concepts in medicine and the life sciences cannot be understood as historically constant, free-standing ideas, but have to be regarded as dependent on local research settings. They often carry particular “social memories” with them and thus acquire important ethical implications. (shrink)

: This interpretation of Zhuangzi's Dao, particularly in the "Qi Wu Lun," as "background noise" begins from Zhuangzi's question as to whether any human statements—and human language itself—can ultimately be distinguished from the "peeps of baby birds." The essay explores a tentative model of Dao that sees it as neither fully "linguistic" nor "non-linguistic" but as "pre-linguistic," the potential ground of emergence of words, statements, and meanings. To develop this model we turn to the notion of background noise in physics, (...) especially as discussed by Michel Serres in his discussion of chaos and information theory. A crucial feature of the Serresian chaos-theory model and also, it is suggested here, of Zhuangzi's Dao is the tendency of hyper-order to return (or switch) back to the initial state of disorder. (shrink)

This interpretation of Zhuangzi's Dao, particularly in the "Qi Wu Lun," as "background noise" begins from Zhuangzi's question as to whether any human statements-and human language itself-can ultimately be distinguished from the "peeps of baby birds." The essay explores a tentative model of Dao that sees it as neither fully "linguistic" nor "non-linguistic" but as "pre-linguistic," the potential ground of emergence of words, statements, and meanings. To develop this model we turn to the notion of background noise in physics, especially (...) as discussed by Michel Serres in his discussion of chaos and information theory. A crucial feature of the Serresian chaos-theory model and also, it is suggested here, of Zhuangzi's Dao is the tendency of hyper-order to return (or switch) back to the initial state of disorder. (shrink)