The wealthy elite males of nineteenth-century Krummhörn (Ostfriesland, Germany) achieved an above-average reproductive success. Membership in the elite class was determined from a list of the 300 richest men in the Ostfriesland district compiled by authorities in 1812. The main components establishing the link between cultural success and reproductive success aredifferences in the number of offspring owing to differences both in time spent in fecund marriage (mating success) and in rate of reproduction;differences in the probabilities (...) of one’s adult offspring marrying locally vs. emigrating unmarried owing to differential ability to allocate resources that enhance the “social placement” of adult offspring; anddifferences in the probability of total reproductive failure (lineage extinction).Contrary to what might be expected, infant survivorship was lowest amongst the richest families. We conclude that to a great extent females’ reproductive decisions contribute to the greater reproductive success of the elite males. (shrink)

The finding that women are attracted to men older than themselves whereas men are attracted to relatively younger women has been explained by social psychologists in terms of economic exchange rooted in traditional sex-role norms. An alternative evolutionary model suggests that males and females follow different reproductive strategies, and predicts a more complex relationship between gender and age preferences. In particular, males' preferences for relatively younger females should be minimal during early mating years, but should become more pronounced as (...) the male gets older. Young females are expected to prefer somewhat older males during their early years and to change less as they age. We briefly review relevant theory and present results of six studies testing this prediction. Study 1 finds support for this gender-differentiated prediction in age preferences expressed in personal advertisements. Study 2 supports the prediction with marriage statistics from two U.S. cities. Study 3 examines the cross-generational robustness of the phenomenon, and finds the same pattern in marriage statistics from 1923. Study 4 replicates Study 1 using matrimonial advertisements from two European countries, and from India. Study 5 finds a consistent pattern in marriages recorded from 1913 through 1939 on a small island in the Philippines. Study 6 reveals the same pattern in singles advertisements placed by financially successful American women and men. We consider the limitations of previous normative and evolutionary explanations of age preferences and discuss the advantages of expanding previous models to include the life history perspective. (shrink)

Studies of multiple paternity in mammals and other animal species generally report proportion of multiple paternity among litters, mean litter sizes, and mean number of sires per litter. It is shown how these variables can be used to produce an estimate of the probability of reproductive success for a male that has mated with a female. This estimate of male success is more informative about the mating system that alternative measures, like the proportion of litters (...) with multiple paternity or the mean number of sires per litter. The probability of success for a mated male can be measured both theoretically and empirically, and gives an estimate of the intensity of sperm competition and of a male's “confidence of paternity” upon mating. The probability of success for mated males for ten “exemplar” species of mammals is estimated and they are compared for insights into the functioning of their mating systems. (shrink)

It has been argued that Pyrrhonists will have trouble acquiescing in the religious practices of their compatriots, since those practices depend on beliefs that are supposedly eliminated by suspension of judgement. According to this objection ..., the Sceptic’s religious behaviour will be inescapably disingenuous. As a way out of this predicament, some interpreters have suggested that the sort of religion that Sextus was familiar with did not require the kind of belief that is subjected to Sceptical examination. This, however, acquits (...) Sextus of the charge of insincerity at the price of taking religious behaviour to be a culturally contingent exception to, rather than a standard case of, Pyrrhonian conduct. Another worry concerns the fixity of Sextus’ philosophical agenda. The argument in PH 3 concludes that, if one goes by what dogmatic philosophers have to say, one will be forced to think that god is inconceivable. By contrast, the first part of the M 9 section on theology argues not for suspension of judgement across the board, but only for the more modest claim that several noteworthy explanations of the emergence of religious belief are unsatisfactory. Insofar as this is the case, M 9 fails to live up to the standard set by PH 3, a failure due either to authorial incompetence or to a difference in philosophical objective. If that is the case, then the two discussions cannot be read as successful examples of the same philosophical outlook. In this paper, I argue for a comprehensive reading of Sextus’ take on religious matters that responds to these worries. In the first half of the paper, I present the two caveats as formulating a uniform agenda concerning theology (Section 1) which is further consistent with the Pyrrhonian stance as presented in PH 1 (Section 2). I show not only that Sextan Sceptics are able to engage in ordinary religious practices, but also that they can do so whether or not their cultural environment takes these practices to depend on holding dogmatic beliefs. In the second half of the paper, I argue by way of a detailed analysis that both PH 3 and M 9 are intended to motivate suspension of judgement about highly specific dogmatic tenets, and while their sources and targets might change, their intended outcome remains the same. The argument in PH 3, often understood as a sort of ‘master argument’ aimed at disarming a broad theistic consensus, depends in fact on peculiar commitments concerning the nature of inquiry (Section 3). The conceptual section of M 9 incorporates explicitly dogmatic—and quite plausibly Epicurean—material in order to argue for suspension of judgement about yet another issue, namely, the question of the natural or conventional origin of the concept of god (Section 4). (shrink)

Philosophers of science are divided over the interpretations of scientific normativity. Larry Laudan defends a sort of goal-directed rules for scientific methodology. In contrast, Gerard Doppelt thinks methodological rules are a mixed batch of rules in that some are goal-oriented hypothetical rules and others are goal-independent categorical rules. David Resnik thinks that the debate between them is at a standstill now. He further thinks there are certain rules, such as the rule of consistency which is goal independent. However, he proposes (...) a holistic understanding of the scientific methodology. Taking a thread from Resnik, the present paper also advocates a holistic understanding of the scientific methodology. Given that many scientific practices deal with systems, the focus will be given to the systems by assuming each as a constellation of methodological norms. By taking each system as a set of mutually supportive methodological rules whose instrumental values underwrite the coherence relation among them, the paper aims to provide what could be a viable holistic epistemological account that can explain scientific normativity at work in a scientific system. The paper will lay down specific holistic criteria for understanding the scientific methodology. They will be used to show how a holistic account could satisfactorily account for the success of the Compact Muon Solenoid (CMS) experiment in discovering the Higgs boson and how the holistic account can account for the instrumental error behind the apparent faster-than-light neutrino anomaly of the Oscillation Project with Emulsion-t Racking Apparatus (OPERA) experiments respectively. (shrink)

Philosophers of science are divided over the interpretations of scientific normativity. Larry Laudan defends a sort of goal-directed rules for scientific methodology. In contrast, Gerard Doppelt thinks methodological rules are a mixed batch of rules in that some are goal-oriented hypothetical rules and others are goal-independent categorical rules. David Resnik thinks that the debate between them is at a standstill now. He further thinks there are certain rules, such as the rule of consistency which is goal independent. However, he proposes (...) a holistic understanding of the scientific methodology. Taking a thread from Resnik, the present paper also advocates a holistic understanding of the scientific methodology. Given that many scientific practices deal with systems, the focus will be given to the systems by assuming each as a constellation of methodological norms. By taking each system as a set of mutually supportive methodological rules whose instrumental values underwrite the coherence relation among them, the paper aims to provide what could be a viable holistic epistemological account that can explain scientific normativity at work in a scientific system. The paper will lay down specific holistic criteria for understanding the scientific methodology. They will be used to show how a holistic account could satisfactorily account for the success of the Compact Muon Solenoid (CMS) experiment in discovering the Higgs boson and how the holistic account can account for the instrumental error behind the apparent faster-than-light neutrino anomaly of the Oscillation Project with Emulsion-t Racking Apparatus (OPERA) experiments respectively. (shrink)

Gellner relied extensively on the work of Ibn Khaldun to understand both the dynamics of social order in North Africa and Islam’s alleged resistance to secularization. However, what the two scholars also shared is their focus on the social origins and functions of group solidarity. For Ibn Khaldun the concept of asabiyyah was central in understanding the strength of long-term group loyalties. In his view, asabiyyah was a fundamental and elementary cohesive bond of human societies which originated in nomadic tribal (...) structures and retained significance in the early formation of complex states and empires. For Gellner, the shape and character of group solidarity is heavily dependent on the economic foundations of a particular social order: foragers require small group bonds for mere survival, the agrarian universe stratifies solidarity and utilizes cultural bonds to differentiate between the ruling aristocrats and the plough-tied serfs, whereas the industrial world generates solidarity from incessant economic growth and state-induced, cross-class, national identifications. Thus, for Gellner, solidarity remains the central force that keeps social orders together. This paper provides a critical analysis of the Khaldunian and Gellnerian models of group solidarity and offers an alternative interpretation that places the social impact of micro-solidarity in the long-term development of ideological and coercive forms of social organization. (shrink)

This study investigates the relative impacts of the facial width-to-height ratio on the first impressions business professionals form of business consultants when seeing their photographs on a corporate website or LinkedIn page. By applying conjoint analysis on field experiment data, we find that in a zero-acquaintance situation business professionals prefer low-fWHR business consultants. This implies that they prefer a face that communicates trustworthiness to one that communicates success. Further, we have investigated the words that business professionals use to describe (...) their preferred consultant. These approach motivations help practitioners to improve the picture-text alignment. The results underline the necessity to critically assess the pictures and text used on websites and media platforms such as LinkedIn for business purposes, and to see them as a key element of business and self-communication that can be altered in order to improve business ‘mating.’. (shrink)

Patterns of three variables of reproductive strategies in male New World primates are examined: (i) how males obtain access to potential mates; (ii) how males obtain actual mating opportunities; and (iii) how males affect infant survival and female reproductive success. Male opportunities to associate with females, whether by remaining in their natal groups, dispersing and forming new groups, or dispersing and taking over or joining established groups, are strongly influenced by local population densities and correlate with (...) female reproductive rates and the extent of female reproductive seasonality and synchrony. Differences in male mating success are affected by female accessibility, whether male-male and male-female relationships are hierarchical or egalitarian, and whether female reproduction is seasonally restricted. Patterns of male behavior toward infants, characterized as active assistance, overt interference, or benign tolerance, appear to co-vary with differences in the degree to which males can affect female reproductive rates.These qualitative analyses suggest that the reproductive strategies of male New World primates can be classified along a continuum ranging from conservative to daring depending on whether female reproductive rates are relatively slow or fast and whether reproduction is strongly or weakly linked to seasonal ecological variables. Males adopt the conservative strategy of staying in their natal groups, forfeiting exclusive mating opportunities, and treating infants with tolerance when female reproduction is constrained by ecological factors. Conversely, males adopt the more daring strategy of dispersing and competing when potential payoffs through their ability to affect female reproduction are high. (shrink)

Researchers studying human sexuality have repeatedly concluded that men place more emphasis on the physical attractiveness of potential mates than women do, particularly in long-term sexual relationships. Evolutionary theorists have suggested that this is the case because male mate value (the total value of the characteristics that an individual possesses in terms of the potential contribution to his or her mate’s reproductive success) is better predicted by social status and economic resources, whereas women’s mate value hinges on signals (...) conveyed by their physical appearance. This pattern may imply that women trade off attractiveness for resources in mate choice. Here I test whether a trade-off between resources and attractiveness seems to be occurring in the mate choice decisions of women in the United States. In addition, the possibility that the risk of mate desertion drives women to choose less attractive men as long-term mates is tested. The results were that women rated physically attractive men as more likely to cheat or desert a long-term relationship, whereas men did not consider attractive women to be more likely to cheat. However, women showed no aversion to the idea of forming long-term relationships with attractive men. Evidence for a trade-off between resources and attractiveness was found for women, who traded off attractiveness, but not other traits, for resources. The potential meaning of these findings, as well as how they relate to broader issues in the study of sex differences in the evolution of human mate choice for physical traits, is discussed. (shrink)

Analysis of sites of newly integrated DNA in cellular genomes is important to several fields, but methods for analyzing and visualizing these datasets are still under development. Here, we describe tools for data analysis and visualization that take as input integration site data from our INSPIIRED pipeline. Paired-end sequencing allows inference of the numbers of transduced cells as well as the distributions of integration sites in target genomes. We present interactive heatmaps that allow comparison of distributions of integration sites to (...) genomic features and that support numerous user-defined statistical tests. To summarize integration site data from human gene therapy samples, we developed a reproducible report format that catalogs sample population structure, longitudinal dynamics, and integration frequency near cancer-associated genes. We also introduce a novel summary statistic, the UC50, which provides a single number summarizing possible clonal expansion. Using these tools, we characterize ongoing longitudinal characterization of a patient from the first trial to treat severe combined immunodeficiency-X1, showing successful reconstitution for 15 years accompanied by persistence of a cell clone with an integration site near the cancer-associated gene CCND2. Software is available at https://github.com/BushmanLab/INSPIIRED. (shrink)

Previous research in North America has supported the view that male involvement in committed, romantic relationships is associated with lower testosterone (T) levels. Here, we test the prediction that undergraduate men involved in committed, romantic relationships (paired) will have lower T levels than men not involved in such relationships (unpaired). Further, we also test whether these differences are more apparent in samples collected later, rather than earlier, in the day. For this study, 107 undergraduate men filled out a questionnaire (...) and collected one saliva sample (from which a subject’s T level was measured) at various times across the day. As in previous studies, men involved in committed, romantic relationships had lower salivary T levels, though only during later times of the day. Furthermore, additional analysis of the variation among unpaired subjects indicated that men without prior relationship experience had lower T levels than experienced men. Finally, while paired men as a group had lower T levels than unpaired men, those men at the earliest stage (less than six months) of a current relationship had higher T levels than unpaired men as well as men in longer-term relationships. These results suggest that variation in male testosterone levels may reflect differential behavioral allocation to mating effort. (shrink)

In most social species, position in the male social hierarchy and reproductive success are positively correlated; in humans, however, this relationship is less clear, with studies of traditional societies yielding mixed results. In the most economically advanced human populations, the adaptiveness of status vanishes altogether; social status and fertility are uncorrelated. These findings have been interpreted to suggest that evolutionary principles may not be appropriate for the explanation of human behavior, especially in modern environments. The present study tests (...) the adaptiveness of social status with actual mating and reproductive data in a representative sample of males from an industrial society. Reproductive success, even when assessed by a more reliable measure ofactualmale fertility than the one commonly used, fails to correlate with social status. In striking contrast, however, status is found to be highly correlated withpotentialfertility, as estimated from copulation frequency. Status thus accounts for as much as 62% of the variance in thisproximatecomponent of fitness. This pattern is remarkably similar to what is found in many traditional societies and would result in a substantial positive relationship between cultural and reproductive success in industrial populations were it not for the novel conditions imposed by contraception and monogamy. Various underlying mechanisms are suggested for these findings, illustrating the value of current behavioral and reproductive data in the study of adaptation. It is concluded that evolutionary explanations of human behavior remain entirely relevant in modern societies. (shrink)

Darwin's “mystery of mysteries,” the origin of species, is caused by the evolution of speciation phenotypes, i.e. phenotypic differences that depress gene flow between daughter species during speciation. Postmating, prezygotic (PMPZ) differentiation characterizes many closely related species causing conspecific sperm precedence (CSP), wherein a female preferentially utilizes conspecific over heterospecific sperm in fertilization. Until recently, the components of CSP have been difficult to observe and study in internally fertilizing organisms. Research into the mechanisms of CSP is now progressing rapidly with (...) the help of new innovative research tools. With the recent development of a sperm labeling system enabling distinct labels for different males, direct observations of competing male sperm within the female reproductive tract are possible, revealing multiple PMPZ phenotypes that combine to cause CSP. The discovery of mechanisms underlying CSP predicts an exciting future for studies of PMPZ speciation phenotypes and possible general principles underlying the origin of species. (shrink)

Plant reproduction is vital for species survival, and is also central to the production of food for human consumption. Seeds result from the successful fertilization of male and female gametes, but our understanding of the development, differentiation of gamete lineages and fertilization processes in higher plants is limited. Germ cells in animals diverge from somatic cells early in embryo development, whereas plants have distinct vegetative and reproductive phases in which gametes are formed from somatic cells after the plant has (...) made the transition to flowering and the formation of the reproductive organs. Recently, novel insights into the molecular mechanisms underlying male germ‐line initiation and male gamete development in plants have been obtained. Transcriptional repression of male germ‐line genes in non‐male germ‐line cells have been identified as a key mechanism for spatial and temporal control of male germ‐line development. This review focuses on molecular events controlling male germ‐line development especially, on the nature and regulation of gene expression programs operating in male gametes of flowering plants. BioEssays 29:1124–1132, 2007. © 2007 Wiley Periodicals, Inc. (shrink)

Male-male competition is involved in inter- and intrasexual selection, with both endocrine and psychological factors presumably contributing to reproductive success in human males. We examined relationships among men’s naturally occurring testosterone, their self-perceived mate value, self-esteem, sociosexuality, and expected likelihood of approaching attractive women versus situations leading to child involvement. We then monitored changes in these measures in male rowers from Cambridge, UK, following a manipulated “win” or “loss” as a result of an indoor rowing contest. (...) Baseline results revealed that men with heightened testosterone and SPMV values typically had greater inclinations toward engaging in casual sexual relationships and a higher likelihood of approaching attractive women in a hypothetical social situation. As anticipated, both testosterone and SPMV increased following a manipulated “victory” and were associated with heightened sociosexuality, and increased expectations toward approaching attractive women versus individuals who would involve them in interacting with children after the race. SPMV and self-esteem appeared to mediate some of the effects of testosterone on post-race values. These findings are considered in the broader context of individual trade-offs between mating and parental effort and a model of the concurrent and dynamic androgenic and psychological influences contributing to male reproductive effort and success. (shrink)

Ramathal et al. have employed an elegant xenotransplantation technique to study the fate of human induced pluripotent stem cells (hiPSCs) from fertile males and from males carrying Y chromosome deletions of the azoospermia factor (AZF) region. When placed in a mouse testis niche, hiPSCs from fertile males differentiate into germ cell‐like cells (GCLCs). Highlighting the crucial role of cell autonomous factors in male sterility, hiPSCs derived from azoospermic males prove to be less successful under similar circumstances. Their studies argue (...) that the agametic “Sertoli cell only” phenotype of two of the AZF deletions likely arises from a defect in the maintenance of germline stem cells (GSCs) rather than from a defect in their specification. These observations underscore the importance of the dialogue between the somatic niche and its inhabitant stem cells, and open up interesting questions concerning the functioning of the somatic niche and how it communicates to the GSCs. (shrink)

Two recent studies have shown a relationship between male height and number of offspring in contemporary developed-world populations. One of them argues as a result that directional selection for male tallness is both positive and unconstrained. This paper uses data from a large and socially representative national cohort of men who were born in Britain in March 1958. Taller men were less likely to be childless than shorter ones. They did not have a greater mean number of children. (...) If anything, the pattern was the reverse, since men from higher socioeconomic groups tended to be taller and also to have smaller families. However, clear evidence was found that men who were taller than average were more likely to find a long-term partner, and also more likely to have several different long-term partners. This confirms the finding that tall men are considered more attractive and suggests that, in a noncontracepting environment, they would have more children. There is also evidence of stabilizing selection, since extremely tall men had an excess of health problems and an increased likelihood of childlessness. The conclusion is that male tallness has been selected for in recent human evolution but has been constrained by developmental factors and stabilizing selection on the extremely tall. (shrink)

Differentiated instruction is an approach that centers on the fact that every student is different and shapes the teaching process according to this reality. Students in the learning environment differ from each other in terms of characteristics such as prior knowledge, interest, needs, learning style, socio-cultural background, cognitive-affective-psychomotor readiness. In order for students with different characteristics to benefit from education in the best way, it is necessary to diversify education in terms of content, teaching-learning process and measurement-evaluation dimensions, taking these (...) differences into account. In this diversification, students' readiness, interest and learning profiles are taken into account as a whole. Although educational programs are prepared by taking the similarities between individuals into account in practice, teachers are expected to diversify the process by taking the individual differences of the students into account and design different learning paths for students with different characteristics. One of the areas that needs to be planned and implemented with a differentiated teaching approach within formal education is religious education. Differentiated religious teaching is to diversify religious teaching in terms of content, learning-teaching process and measurement and evaluation dimensions, taking the individual differences of students into account such as their prior religious knowledge, interest and attitudes towards religion, cultural affiliations and learning profiles. In this study, the self-efficacy perceptions of Religious Culture and Moral Knowledge (“Din Kültürü ve Ahlâk Bilgisi”, abb. DKAB in Turkish) teachers towards differentiated teaching were examined. Determining the self-efficacy perceptions of DKAB teachers regarding differentiated instruction is important in terms of providing information about their success in planning, implementing and evaluating according to differentiated instruction in the Religious Culture and Moral Knowledge course. The research sought answers to the following questions: 1. What are DKAB teachers' self-efficacy perceptions towards differentiated instruction? 2. Is there a significant relationship between DKAB teachers' self-efficacy perceptions towards differentiated instruction and teachers' gender, age, years of service, graduated higher education program and the type of school they work in? The research is a descriptive study and is of quantitative type and survey model. The population of the research consists of DKAB teachers working in primary and secondary education institutions in the 2nd semester of the 2021-2022 academic year. The sample of the research consists of 425 DKAB teachers selected from the population using the appropriate sampling method. Differentiated Instruction Self-Efficacy Scale developed by Mutlu, Öztürk and Aktekin was used to collect the data used in the research. The data collected in the study was analyzed using the SPSS 25.0 package program. According to the findings obtained in the study, DKAB teachers' self-efficacy perceptions regarding differentiated instruction are at a high level. The characteristics of DKAB teachers' age, years of service, and the type of school they work in do not have a significant effect on teachers' self-efficacy perceptions regarding differentiated instruction. There is a significant relationship between DKAB teachers' gender and the characteristics of the higher education program they graduated from and their self-efficacy perceptions. Male teachers consider themselves more competent in differentiated instruction. The self-efficacy perceptions of the teachers who graduated from the primary education DKAB Teaching program are at a higher level than the teachers who graduated from the theology (Ilahiyat) program, which is described as the faculty of theology. It is thought that the research will contribute to the field of differentiated religious teaching. (shrink)

This study aims to investigate assortative mating based on mate value from male perspective. Male participants (132 Brazilian and 106 American) evaluated hypothetical “stimulus” males described in terms of physical attractiveness, social skills, and social status (each varied in high or low levels). Participants rated each stimulus and each stimulus' preferred mating partner on nine traits. The results showed that (1) positive assortative mating was expected in romantic relationships; (2) the stimulus ratings did not vary (...) independently, suggesting that mate value is the result of the interaction of the characteristics of individuals; and (3) that participants expected physically attractive and healthier female partners to pair with high-status male stimuli. The American and Brazilian mating expectations were similar, minor differences indicate that Brazilian participants considered men with high levels of social skills to be more ambitious and intelligent; American participants expected men of high status to be healthier; Brazilians expect men of high status to have more attractive faces, while Americans expected these men to possess more attractive bodies; and Brazilian participants assigned more attractive bodies to men of lower status. These differences reflect the influence of economic and cultural factors on the local environment. The study contributes to the understanding of the construction of market value and reveals that male expectations are in line with human mating preferences. The investigation of mating expectations can be a rich approach to investigate socio-cultural aspects that are related to mating in different cultures. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:The Tragic Evolutionary Logic of The IliadBrian BoydThe Rape of Troy: Evolution, Violence, and the World of Homer, by Jonathan Gottschall; xii & 223 pp. Cambridge: Cambridge University Press, 2008, $32.00 paperback.Jonathan Gottschall has conquered the oldest and craggiest peak of Western literature, The Iliad, by a new face. He stakes out the Darwin route to Homer so directly and clearly that he makes the climb inviting and inspiring (...) even to curious newcomers without high-altitude evolutionary training. And the vista he opens up offers us a chance to look in multiple directions: at Homer, at literary evolutionism and its possibilities, and at Gottschall's role in exploring this new route to discovery.One previous monograph has investigated a single literary work from a Darwinian viewpoint: Brett Cooke's analysis of Evgeny Zamyatin's 1921 science-fiction classic, We.1 Cooke's Human Nature in Utopia, by showing how Zamyatin appeals to the evolved nature of readers, in the face of the denial of human nature in his imagined One State and in early Soviet Communism, deepens our natural response to a modern classic. But where Cooke merely succeeds, Gottschall triumphs. The Rape of Troy not only deepens our response to a classic discussed for almost three millennia but also explains the world of Homer in a way no one could have seen without the multi-million-year perspective evolution allows—and does so with conceptual clarity, tight argument, effortless imagery, and copious verbal energy. [End Page 234]Gottschall emphasizes that his "evolutionary anthropology of conflict in Homeric society" does not attempt a Homeric "theory of everything" (pp. 3, 9). There is much of interest in The Iliad he does not touch on, and much even in possible evolutionary approaches to Homer that he does not consider. He focuses intently on a single two-part question: Why is there so much violence in the Iliad, and what effect does it have on how those in Homeric society see their world?After a brilliant introductory overview, he shows in his first two chapters how over the last century Homerists have increasingly turned to comparative anthropology to augment the meagre direct data. They have clarified that the Iliad was long obscured by later Western assumptions about states and kings, and that the poem probably reflects something like Homer's own world, within (at about 800 BCE) the late Greek Dark Age, a pre-state society in many ways closer to Highland New Guinea than to the worlds of Caesar or Charlemagne.Everyone who knows about the Trojan War knows that the Greeks fight Troy because the Trojan prince Paris took Helen from her husband, the Greek lord Menelaus. But readers of the Iliad want to know why thousands of soldiers on both sides persisted through ten years of brutal battle. Surely war on this scale cannot have been over just a woman? Scholars have proposed many explanations of what was really at stake. Immortal honor for men all too aware, day after bloody day, of their own physical mortality? Power? Status? Material goods? Prestige goods? A chance to neutralize enemies?By drawing on evolutionary biology and anthropology, Gottschall can show that this war, like most human violence against other humans, and even like most intraspecies animal violence, stems ultimately from male competition over females. He introduces the powerful and far-reaching principle of differential parental investment developed by Robert Trivers.2 As Gottschall lucidly elaborates: "males will attempt to mate more promiscuously both because sex is cheaper for them, and because they have the potential to produce many offspring with multiple females. I emphasize the words 'attempt' and 'potential' because if every male adopts a relatively promiscuous strategy, and if some males succeed, then other males will not reproduce at all" (p. 44). The far more divergent rates of reproductive success among males than among females prove to be the key determinant. Gottschall sums up: "males typically face higher risks of total reproductive failure and higher hopes of extraordinary reproductive success. This creates strong incentives to compete for mates. Males who are better able to compete for access to [End Page 235] scarce female reproductive capacity, in whatever form... (shrink)

The finding that women are attracted to men older than themselves whereas men are attracted to relatively younger women has been explained by social psychologists in terms of economic exchange rooted in traditional sex-role norms. An alternative evolutionary model suggests that males and females follow different reproductive strategies, and predicts a more complex relationship between gender and age preferences. In particular, males' preferences for relatively younger females should be minimal during early mating years, but should become more pronounced as (...) the male gets older. Young females are expected to prefer somewhat older males during their early years and to change less as they age. We briefly review relevant theory and present results of six studies testing this prediction. Study 1 finds support for this gender-differentiated prediction in age preferences expressed in personal advertisements. Study 2 supports the prediction with marriage statistics from two U.S. cities. Study 3 examines the cross-generational robustness of the phenomenon, and finds the same pattern in marriage statistics from 1923. Study 4 replicates Study 1 using matrimonial advertisements from two European countries, and from India. Study 5 finds a consistent pattern in marriages recorded from 1913 through 1939 on a small island in the Philippines. Study 6 reveals the same pattern in singles advertisements placed by financially successful American women and men. We consider the limitations of previous normative and evolutionary explanations of age preferences and discuss the advantages of expanding previous models to include the life history perspective. (shrink)

Over the course of the 20th century the sex differential in life expectancy at birth in the industrialized countries has widened considerably in favour of women. Starting in the early 1970s, the beginning of a reversal in the long-term pattern of this differential has been noted in some high-income countries. This study documents a sustained pattern of narrowing of this measure into the later part of the 1990s for six of the populations that comprise the G7 countries: Canada, (...) France, Germany, Italy, England and Wales (as representative of the United Kingdom) and USA. For Japan, a persistence of widening sex differences in survival is noted. The sex differences in life expectancy are decomposed over roughly three decades (early 1970s to late 1990s) from the point of view of four major cause-of-death categories: circulatory diseases, cancers, accidents/violence/suicide, and (residual) causes. In the six countries where the sex gap has narrowed, this has resulted primarily from reduced sex differences in circulatory disease mortality, and secondarily from reduced differences in male and female death rates due to accidents, violence and suicide combined. In some of the countries sex differentials in cancer mortality have been converging lately, and this has also contributed to a narrowing of the difference in life expectancy. In Japan, males have been less successful in reducing their survival disadvantage in relation to Japanese women with regard to circulatory disease and cancer; and in the case of accidents/violence/suicide, male death rates increased during the 1990s. These trends explain the divergent pattern of the sex difference in life expectation in Japan as compared with the other G7 nations. (shrink)

Not all of the studies cited in the target article as evidence that fluctuating asymmetry (FA) predicts male mating success demonstrate that the observed asymmetry is, in fact, FA. FA is a population-level pattern of differences between sides. Unless the population-level distributional criteria of bilateral traits are reported, the meaning of asymmetry in individuals is unknown.

Humans have a complex and dynamic mating system, and there is evidence that our modern sexual preferences stem from evolutionary pressures. In the current paper we explore male use of a dual mating strategy: simultaneously pursuing both a long-term relationship (pair-bonding) as well as short-term, extra-pair copulations (variety-seeking). The primary constraint on such sexual pursuits is partner preferences, which can limit male behavior and hence cloud inferences about male preferences. The aim of this study was (...) to investigate heterosexual male mating preferences when largely unconstrained by female partner preferences. In service of this goal, female full-service sex workers (N = 6) were surveyed on the traits and behaviors of their male clients (N = 516) and iterative cluster analysis was used to identify male mating typologies. Two clusters emerged: clients seeking a pair-bonding experience and clients seeking a variety experience. Results also suggested that romantically committed men were more likely to seek a variety experience than a relationship experience. We conclude that men desire both pair-bonding and sexual variety, and that their preference for one might be predicted by fulfilment of the other. These findings have implications for relationships, providing insight into motivations for male infidelity. (shrink)

Zusammenfassung Im Rahmen dieses Beitrags soll der Versuch unternommen werden, eine Antwort auf die Frage zu geben, welche Faktoren für den sportlichen Erfolg im modernen Berufsfußball verantwortlich sind bzw. hinsichtlich welcher Faktoren sich die sportlich erfolgreichen Vereine von den weniger erfolgreichen Vereinen unterscheiden. In diesem Zusammenhang ist insbesondere von Interesse, ob der sportliche Erfolg, wie vielfach behauptet wird, ausschließlich von monetären Faktoren determiniert wird und damit sprichwörtlich käuflich ist. Zu diesem Zweck wird eine diskriminanzanalytische Untersuchung möglicher Erfolgsfaktoren durchgeführt, wobei es (...) das umfangreich verfügbare Datenmaterial erlaubt, insgesamt 18 erfolgsrelevante Merkmalsvariablen in die Analysen einzubeziehen. (shrink)

This paper reviews the work on gendered achievement in the English?speaking Caribbean, with its often explicit focus on underachieving males. However, patterns of gendered achievement are more likely region?specific and variegated in some contexts. In Trinidad and Tobago, the full?scale implementation of national assessments in 2004 provided an opportunity to evaluate mathematics and language performance across the entire pupil population at standards 1 (7? to 8?year?olds) and 3 (9? to 10?year?olds). Census data from the high?stakes 2003 Secondary Entrance Assessment (SEA) (...) administered at standard 5 (ages: 10?11+) were also included in the analysis. Therefore the entire dataset consisted of 52,284 primary school students (26,574 males and 25,710 females). The findings confirmed that female pupils had a statistically significant advantage on all assessments. However, in terms of practical significance, most differentials were negligible to small. Medium?sized differentials were obtained for pupils of low ability, living in rural educational districts, and on language arts. Male achievement scores were also more variable for lower grade levels, low ability groups and language arts. Paradoxically, in some educational districts secondary school placement opportunities still favoured males. These variegated patterns of gendered achievement may be associated with differences in institutional effectiveness and variations in male socialization practices that are especially evident across the urban?rural divide. (shrink)

We report three studies which test a sexual selection hypothesis for male war heroism. Based on evolutionary theories of mate choice we hypothesize that men signal their fitness through displaying heroism in combat. First, we report the results of an archival study on US-American soldiers who fought in World War II. We compare proxies for reproductive success between a control sample of 449 regular veterans and 123 surviving Medal of Honor recipients of WWII. Results suggest that the heroes (...) sired more offspring than the regular veterans. Supporting a causal link between war heroism and mating success, we then report the results of two experimental studies. We find evidence that female participants specifically regard men more sexually attractive if they are war heroes. This effect is absent for male participants judging female war heroes, suggesting that bravery in war is a gender specific signal. Finally, we discuss possible implications of our results. (shrink)

O’BYRNE P and WATTS J. Nursing Inquiry 2012 [Epub ahead of print] Include, differentiate and manage: gay male youth, stigma and healthcare utilizationIn Canada, there has been a recent increase in HIV incidence among young men who have sex with men. However, gay male youth (GMY) may forego HIV testing due to fear of stigmatization. Therefore, the aim of this research was to explore the perceptions of stigma in health care within this population. The research was conducted through (...) a series of semi‐structured interviews with eight GMY aged 20–29, who frequented a gay‐friendly clinic in downtown Ottawa, Canada. In a sub‐analysis of the interviews utilizing the work of Hardt and Negri’s three‐part sequence – inclusion, differentiation and management – we found that homosexuality‐related stigmatization affects the interaction between GMY and health professionals. Interview participants perceived HIV‐related risk counselling as a manifestation of stigma. These findings reveal that the experience of stigma and stigmatization is not necessarily based on health professionals’ intentions, but rather, on patients’ perceptions of the interactions they have with health professionals. Specific modifications to the delivery of health care may help to overcome stigmatization. (shrink)

In previous research, acoustic characteristics of the male voice have been shown to signal various aspects of mate quality and threat potential. But the human voice is also a medium of linguistic communication. The present study explores whether physical and vocal indicators of male mate quality and threat potential are linked to effective communicative behaviors such as vowel differentiation and use of more salient phonetic variants of consonants. We show that physical and vocal indicators of male threat (...) potential, height and formant position, are negatively linked to vowel space size, and that height and levels of circulating testosterone are negatively linked to the use of the aspirated variant of the alveolar stop consonant /t/. Thus, taller, more masculine men display less clarity in their speech and prefer phonetic variants that may be associated with masculine attributes such as toughness. These findings suggest that vocal signals of men’s mate quality and/or dominance are not confined to the realm of voice acoustics but extend to other aspects of communicative behavior, even if this means a trade-off with speech patterns that are considered communicatively advantageous, such as clarity and indexical cues to higher social class. (shrink)

Previous theoretical accounts have predicted that warfare and intergroup conflict are environmental factors that contribute to the emergence of a fast life-history strategy. However, this assumption has never been directly empirically tested. We examined youth who grew up in a territory that experienced violent intergroup conflict and compared them with a control group on various life-history measures: age of first sexual intercourse, mating behavior, desired timing of marriage and first reproduction and desired number of children. We also measured other (...) characteristics to explore the congruence between them and exposure to conflict. Participants from the postconflict society showed indications of faster life-history strategy: greater mating effort, a tendency to marry and have their first child sooner, and a larger desired number of children. Furthermore, interactions between exposure to conflict and participants’ sex were found: females from a postconflict society want to have their child earlier, and males have elevated short-term mating success. Finally, the exposure to violent conflict turned out to have congruent effects with economic poverty but not troublesome family relations. The findings are in accordance with life-history theory and show the adaptiveness of human behavior related to fitness optimization in hostile and dangerous environments. (shrink)

Different housing conditions, including housing space and the physiological and social environment, may affect rodent behavior. Here, we examined the effects of different housing conditions on post-stroke angiogenesis and functional recovery to clarify the ambiguity about environmental enrichment and its components. Male rats in the model groups underwent right middle cerebral artery occlusion followed by reperfusion. The MCAO rats were divided into four groups: the physical enrichment group, the social enrichment group, the combined physical and social enrichment group and (...) the ischemia/reperfusion + standard conditioning group. The rats in the sham surgery group were housed under standard conditions. In a set of behavioral tests, including the modified Neurological Severity Score, rotarod test, and adhesive removal test, we demonstrated that the animals in the enriched condition groups exhibited significantly improved neurological functions compared to those in the standard housing group. Smaller infarction volumes were observed in the animals of the PSE group by MRI detection. The enriched conditions increased the microvessel density in the ischemic boundary zone, as revealed by CD31 immunofluorescent staining. The immunochemical and q-PCR results further showed that environmental enrichment increased the expression levels of angiogenic factors after ischemia/reperfusion injury. Our data suggest that all three enrichment conditions promoted enhanced angiogenesis and functional recovery after ischemia/reperfusion injury compared to the standard housing, while only exposure to the combination of both physical and social enrichment yielded optimal benefits. (shrink)

This study investigates an example of human altruism which is neither kin-directed nor reciprocal: giving to a panhandler. Data were collected on the proportions of passers-by who gave to panhandlers in Boston and Cambridge, Massachusetts. Three hypotheses were tested, each predicting that passers-by should behave “selfishly,” capitalizing on opportunities that, in an evolutionarily appropriate context, could increase mating success. Male passers-by, when alone, gave disproportionately to female panhandlers. Male passers-by, when in the company of a female (...) partner, disproportionately avoided giving to female panhandlers. Male passers-by in the company of a female partner did not “show off” by giving disproportionately to male panhandlers. (shrink)

No single theory so far proposed gives a wholly satisfactory account of the origin and maintenance of bird-song dialects. This failure is the consequence of a weak comparative literature that precludes careful comparisons among species or studies, and of the complexity of the issues involved. Complexity arises because dialects seem to bear upon a wide range of features in the life history of bird species. We give an account of the principal issues in bird-song dialects: evolution of vocal learning, experimental (...) findings on song ontogeny, dialect descriptions, female and male reactions to differences in dialect, and population genetics and dispersal.We present a synthetic theory of the origin and maintenance of song dialects, one that accommodates most of the different systems reported in the literature. The few data available suggest that large, regional dialect populations are genetically differentiated; this pattern is correlated with reduced dispersal between dialects, assortative mating by females, and male-male exclusion. At the same time, “subdialects” may be formed within regional dialects. Subdialect clusters are usually small and may represent vocal mimicry among a few adjacent territorial males. The relative importance of genetic and social adaptation may contribute to the emergence of subdialects; their distinctiveness may be correlated with the degree of polygyny, for example. Thus, subdialect formation is linked to one theory of the evolution of repertoire size, but data are too fragmentary to examine this idea critically. (shrink)

Drosophila males sing a courtship song to achieve copulations with females. Females were recently found to sing a distinct song during copulation, which depends on male seminal fluid transfer and delays female remating. Here, it is hypothesized that female copulation song is a signal directed at the copulating male and changes ejaculate allocation. This may alter female remating and sperm usage, and thereby affect postcopulatory mate choice. Mechanisms of how female copulation song is elicited, how males respond to (...) copulation song, and how remating is modulated, are considered. The potential adaptive value of female signaling during copulation is discussed with reference to vertebrate copulation calls and their proposed function in eliciting mate guarding. Female copulation song may be widespread within the Drosophila genus. This newly discovered behavior opens many interesting avenues for future research, including investigation of how sexually dimorphic neuronal circuits mediate communication between nervous system and reproductive organs. (shrink)

The average male–female performance difference in the three sports of track athletics, swimming and time trial cycling are examined between the years 1948 and 1976. During this period females have gradually come to participate in a much larger number of events, particularly those of longer duration. In each of these three sports, women's performances in relation to men's have more or less continuously improved and it appears that if the changes between 1948 and 1976 are maintained, average female performance (...) will equal that of males for all events currently competed in by both sexes in these sports at some time during the next century. Estimates as to when, precisely, this will occur vary somewhat according to the basis on which the calculations are made. The other main change evident during these years is that in all three sports women's performances relative to men's for events of long duration have become as good or better than their relative performance at events of short duration. (shrink)

Previous research has shown that the qualities of nuptial gifts among nonhumans and marriage-related property transfers in human societies such as bridewealth and dowry covary with aspects of mate quality. This article explores this issue for another type of marriage-related property transfer: engagement rings. We obtained data on engagement ring costs and other variables through a mail survey sent to recently married individuals living in the American Midwest. This article focuses on survey responses regarding rings that were purchased by men (...) acting alone and using only their own funds who then presented the rings while making surprise proposals of marriage (n = 127). Men marrying younger women spent more on rings, as did men who earned more money and whose fiancées earned more money. These findings suggest that the amounts spent on engagement rings, like bridewealth and dowry payments in other societies, reflect aspects of both male and female mate quality. (shrink)

Many male traits are well explained by sexual selection theory as adaptations to mating competition and mate choice, whereas no unifying theory explains traits expressed more in females. Anne Campbell's “staying alive” theory proposed that human females produce stronger self-protective reactions than males to aggressive threats because self-protection tends to have higher fitness value for females than males. We examined whether Campbell's theory has more general applicability by considering whether human females respond with greater self-protectiveness than males to (...) other threats beyond aggression. We searched the literature for physiological, behavioral, and emotional responses to major physical and social threats, and found consistent support for females' responding with greater self-protectiveness than males. Females mount stronger immune responses to many pathogens; experience a lower threshold to detect, and lesser tolerance of, pain; awaken more frequently at night; express greater concern about physically dangerous stimuli; exert more effort to avoid social conflicts; exhibit a personality style more focused on life's dangers; react to threats with greater fear, disgust, and sadness; and develop more threat-based clinical conditions than males. Our findings suggest that in relation to threat, human females have relatively heightened protective reactions compared to males. The pervasiveness of this result across multiple domains suggests that general mechanisms might exist underlying females' unique adaptations. An understanding of such processes would enhance knowledge of female health and well-being. (shrink)