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E H Kluge 《CMAJ》1991,144(3):359-360
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Menstrual taboos are nearly ubiquitous and assume parallel forms in geographically distant populations, yet their function has baffled researchers for decades. This paper proposes that menstrual taboos are anticuckoldry tactics. By signaling menstruation, they may advertise female reproductive status to husbands, affines, and other observers. Females may therefore have difficulty in obfuscating the timing of the onset of pregnancy. This may have three consequences: (a) males are better able to assess their probabilities of paternity and to direct their parental investment toward genetic offspring; (b) adulterous pregnancies are more easily detected and penalized, enhancing sexual fidelity; and (c) males avoid marrying pregnant females by relying on menstruation as evidence of nonpregnancy. This hypothesis is tested with 29 months of field data on menstrual taboos among the Dogon of Mali. Key results include the following: (a) cuckoldry is a major Dogon concern, (b) menstrual huts advertise female reproductive status, (c) husbands impose the taboos upon their wives, (d) female defiance of the taboos is undetectable and probably rare, and (e) informants think that the taboos help husbands and patrilineages to avoid cuckoldry. Thus the anti-cuckoldry hypothesis provides helpful insight into the menstrual taboos of the Dogon and should be tested among other populations. This research was supported by The Evolution and Human Behavior Program at the University of Michigan (through Dick Alexander), the L.S.B. Leakey Foundation, and the National Science Foundation (BNS-8612291). Beverly Strassmann is a National Institutes of Health postdoctoral fellow at the Reproductive Sciences Program, University of Michigan. Her primary research interest is human evolutionary ecology, with recent emphasis on menstruation in natural fertility populations, the effect of polygyny on female fitness, and reproductive endocrinology.  相似文献   

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How small can a macroscopic object be made without losing its intended function? Obviously, the smallest possible size is determined by the size of an atom, but it is not so obvious how many atoms are required to assemble an object so small, and yet that performs the same function as its macroscopic counterpart. In this review, we are concerned with objects of intermediate nature, lying between the microscopic and the macroscopic world. In physics and chemistry literature, this regime in-between is often called mesoscopic, and is known to bear interesting and counterintuitive features. After a brief introduction to the concept of mesoscopic systems from the perspective of physics, we discuss the functional aspects of mesoscopic architectures in cell biology, and supramolecular chemistry through many examples from the literature. We argue that the biochemistry of the cell is largely regulated by mesoscopic functional architectures; however, the significance of mesoscopic phenomena seems to be quite underappreciated in biological sciences. With this motivation, one of our main purposes here is to emphasize the critical role that mesoscopic structures play in cell biology and biochemistry.  相似文献   

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How small can a macroscopic object be made without losing its intended function? Obviously, the smallest possible size is determined by the size of an atom, but it is not so obvious how many atoms are required to assemble an object so small, and yet that performs the same function as its macroscopic counterpart. In this review, we are concerned with objects of intermediate nature, lying between the microscopic and the macroscopic world. In physics and chemistry literature, this regime in-between is often called mesoscopic, and is known to bear interesting and counterintuitive features. After a brief introduction to the concept of mesoscopic systems from the perspective of physics, we discuss the functional aspects of mesoscopic architectures in cell biology, and supramolecular chemistry through many examples from the literature. We argue that the biochemistry of the cell is largely regulated by mesoscopic functional architectures; however, the significance of mesoscopic phenomena seems to be quite underappreciated in biological sciences. With this motivation, one of our main purposes here is to emphasize the critical role that mesoscopic structures play in cell biology and biochemistry.  相似文献   

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Background

One of the main obstacles for the mainstreaming of religious traditions as tools for the conservation of nature is the limited applicability of research results in this field. We documented two different restrictions implemented by local people (taboos and sacrifices) related to the use of ritual plants in Benin (West Africa) and Gabon (Central Africa).

Methods

To see whether these restrictions reflected plant scarcity from an etic perspective (official threat status) and an emic viewpoint (perceived scarcity by local people), we conducted 102 interviews with traditional healers and adepts of traditional faiths.

Results

We documented a total of 618 ritual plants, from which 52 species were used in both countries. In Benin, the use of 63 of the 414 ritual plant species was restricted; while in Gabon 23 of the 256 ritual plants were associated with taboos and sacrifices. In Benin, restricted plants were significantly more often officially threatened, perceived as scarce, and actively protected than non-restricted plants. In the more forested and less densely populated Gabon, plants that were perceived as scarce were more often associated to local restrictions than officially threatened species.

Conclusions

These results prove the presence of a form of adaptive management where restrictions are related to resource scarcity and protection of ritual plant species. By providing baseline data on possibly endangered species, we demonstrate how plant use in the context of religious traditions can yield important information for conservation planning.

Electronic supplementary material

The online version of this article (doi:10.1186/1746-4269-11-5) contains supplementary material, which is available to authorized users.  相似文献   

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The application of evolutionary theory to understanding the origins of our species'' capacities for social learning has generated key insights into cultural evolution. By focusing on how our psychology has evolved to adaptively extract beliefs and practices by observing others, theorists have hypothesized how social learning can, over generations, give rise to culturally evolved adaptations. While much field research documents the subtle ways in which culturally transmitted beliefs and practices adapt people to their local environments, and much experimental work reveals the predicted patterns of social learning, little research connects real-world adaptive cultural traits to the patterns of transmission predicted by these theories. Addressing this gap, we show how food taboos for pregnant and lactating women in Fiji selectively target the most toxic marine species, effectively reducing a woman''s chances of fish poisoning by 30 per cent during pregnancy and 60 per cent during breastfeeding. We further analyse how these taboos are transmitted, showing support for cultural evolutionary models that combine familial transmission with selective learning from locally prestigious individuals. In addition, we explore how particular aspects of human cognitive processes increase the frequency of some non-adaptive taboos. This case demonstrates how evolutionary theory can be deployed to explain both adaptive and non-adaptive behavioural patterns.  相似文献   

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Baby Check, a scoring system for assessing the severity of illness in babies under 6 months old, has not met with the success its developers expected. The inclusion of rectal temperature in the assessment was strongly opposed by the Royal College of Midwives, which refused to alter its view despite evidence of the safety and accuracy of rectal thermometry. British parents appear not to like rectal thermometers either. Most other medical bodies have supported Baby Check and the reason for midwives'' opposition may have more to do with professional pique at not being consulted than clinical wisdom.  相似文献   

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Systems biology versus molecular biology   总被引:3,自引:0,他引:3  
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Ricquier D 《Comptes rendus biologies》2006,329(8):578-86; discussion 653-5
Thermogenesis is an obligatory consequence of cellular metabolism and is identified as a unique property of homeotherms which have to maintain constant their body temperature in a cold environment. Physiologically, thermogenesis is made of basal metabolism, post-prandial thermogenesis, exercise-induced thermogenesis and adaptive thermogenesis induced by changes in the environmental temperature. Biochemically, thermogenesis comes from exergonic reactions from a loose coupling between endergonic and exergonic reactions. In cells, respiration and oxidations occur in mitochondria which ensure the coupling of oxidative energy to ATP synthesis. Identification of mitochondrial uncoupling proteins UCP allowed further understanding of the mechanism of coupling or uncoupling of respiration to ADP phosphorylation. Such data maybe of help in the understanding, or possible treatment, of certain types of obesity.  相似文献   

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