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51.
This article argues that the rapid transfer of assisted conception technologies, such as in vitro fertilization, to India is not restricted merely to the modalities of offering potential biomedical resolution of infertility but includes, more crucially, how clinicians and infertile consumers assimilate the “Western technoscience” of conception. The article draws on a larger multisite ethnographic study of infertility and assisted conception in India’s five major cities and is principally based on narratives of clinicians and infertile couples and on clinic-based ethnographic observations. In this article I contend that the success or failure of assisted conception, when situated in the universe of Hindu faith, becomes a powerful critique of the “incompleteness” of the “Western” science of conception. Situating this contention in the broader context of a clinician’s faith, I assert that assisted conception—by conjoining seemingly disparate domains of the traditional and the modern, the sacred and the profane, the human and the superhuman, science and religion—produces clinical theodicies that help explain and contain the tentativeness permeating the conception technologies. The article concludes by arguing that this enchanted version of a thoroughly disenchanted worldview of biomedicine is part of a larger cultural process of indigenization of biomedicine in India.  相似文献   
52.
The ultimate causes for predominant male‐biased dispersal (MBD) in mammals and female‐biased dispersal (FBD) in birds are still subject to much debate. Studying exceptions to general patterns of dispersal, for example, FBD in mammals, provides a valuable opportunity to test the validity of proposed evolutionary pressures. We used long‐term behavioural and genetic data on individually banded Proboscis bats (Rhynchonycteris naso) to show that this species is one of the rare mammalian exceptions with FBD. Our results suggest that all females disperse from their natal colonies prior to first reproduction and that a substantial proportion of males are philopatric and reproduce in their natal colonies, although male immigration has also been detected. The age of females at first conception falls below the tenure of males, suggesting that females disperse to avoid father–daughter inbreeding. Male philopatry in this species is intriguing because Proboscis bats do not share the usual mammalian correlates (i.e. resource‐defence polygyny and/or kin cooperation) of male philopatry. They have a mating strategy based on female defence, where local mate competition between male kin is supposedly severe and should prevent the evolution of male philopatry. However, in contrast to immigrant males, philopatric males may profit from acquaintance with the natal foraging grounds and may be able to attain dominance easier and/or earlier in life. Our results on Proboscis bats lent additional support to the importance of inbreeding avoidance in shaping sex‐biased dispersal patterns and suggest that resource defence by males or kin cooperation cannot fully explain the evolution of male philopatry in mammals.  相似文献   
53.
The theoretical system Lyell presented in 1830 was composed of three requirements or principles: 1) the Uniformity Principle which states that past geological events must be explained by the same causes now in operation; 2) the Uniformity of Rate Principle which states that geological laws operate with the same force as at present; 3) the Steady-state Principle which states that the earth does not undergo any directional change. The three principles form a single thesis called uniformitarianism which has been repeatedly questioned and which has been reputed to be unable to face the competing directional synthesis based on the theory of the earth's cooling down. As a result, the significance of Lyell's system has been reduced to a simple actualism which admits the validity of the only Uniformity Principle. I believe that the only way to understand Lyell's role in the history of science is to maintain the unity of his synthesis. To show the Newtonian roots of this synthesis I will compare Lyell's principles and Newton's Rules of Reasoning. I will conclude with an analysis of the methodological function of principles in Lyell's scientific endeavour.  相似文献   
54.
Female northern muriquis (Brachyteles hypoxanthus) are known to engage in frequent copulations with multiple partners, a pattern that in other primates has been attributed to various functions such as confusing paternity, reducing male aggression, or ensuring fertilization. However, in some female primates, promiscuity is restricted to times when conceptions are unlikely. We investigated whether female northern muriquis might exhibit a similarly mixed strategy by examining their mating, social, and activity patterns during their conception cycles versus other times. Systematic behavioral data were collected during an 18-month period between August 2001 and February 2003 on 13 adult females in a well-studied group at the RPPN-Feliciano Miguel Abdala, Minas Gerais, Brazil. Females mated on an average of 12.5+/-7.9 days during the study period, and spent significantly less time resting and engaging in non-sexual social behaviors, and significantly more time in sexual behaviors on days that they copulated than on days they did not. Three of the eight females for which sufficient data were available copulated significantly more often with their spatially closest non-kin associates, and four of five females that could be analyzed copulated significantly more often with their most frequent non-kin embrace partners. Comparisons between conception and non-conception periods revealed no differences in female activity budgets or in either the number of copulations or the number of different mating partners per female. Our results suggest that some females mate preferentially with close associates and social partners, but there is no indication that females alter their behavior during the cycles in which they conceive.  相似文献   
55.
In primates and other mammals, weaning is an equivocal concept, as is reflected in the numerous ways it is measured: a) first intake of solid food, b) conflict over access to the nipple, c) ability to survive without mother, d) maternal resumption of cycling, or e) the cessation of nipple contact. The lack of a consistent definition means that weaning age, although it falls between gestation (fetal growth) and age at first reproduction (most energy diverted from growth), is currently not a reliable life history variable capturing offspring independence. Using data for wild Phayre's leaf monkeys (Trachypithecus phayrei crepusculus) at Phu Khieo Wildlife Sanctuary, Thailand (51 offspring, four groups), we asked whether the end of nipple contact indicates offspring independence as measured by survival to 3 years. To establish a baseline for the onset of independence, we assessed the youngest age at which individuals were orphaned (15–17 months) but then survived to 3 years. Next we determined that offspring age at last nipple contact (19.0 months) was comparable to two other independently calculated measures: offspring age at mother's first postpartum ovulation (11.5 months), and age at mother's re‐conception (15.6 months). Using these separate “starting points,” we arrived at similar ages for nipple contact cessation (18.4 and 19.2 months, respectively). Overall, in wild (but not in provisioned) Asian colobines, age at last nipple contact was allometrically related to adult female body mass, supporting its designation as a life history variable. Future comparisons need to show if this holds for other taxa. Am J Phys Anthropol 154:291–301, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
56.
Heat stress negatively impacts the reproductive performance of dairy cows. The main objective of this study was to dissect the genetic basis underlying dairy cow fertility under heat stress conditions. Our first goal was to estimate genetic components of cow conception across lactations considering heat stress. Our second goal was to reveal individual genes and functional gene-sets that explain a cow’s ability to conceive under thermal stress. Data consisted of 74 221 insemination records on 13 704 Holstein cows. Multitrait linear repeatability test-day models with random regressions on a function of temperature–humidity index values were used for the analyses. Heritability estimates for cow conception under heat stress were around 2–3%, whereas genetic correlations between general and thermotolerance additive genetic effects were negative and ranged between −0.35 and −0.82, indicating an unfavorable relationship between cows’ ability to conceive under thermo-neutral vs. thermo-stress conditions. Whole-genome scans identified at least six genomic regions on BTA1, BTA10, BTA11, BTA17, BTA21 and BTA23 associated with conception under thermal stress. These regions harbor candidate genes such as BRWD1, EXD2, ADAM20, EPAS1, TAOK3, and NOS1, which are directly implicated in reproductive functions and cellular response to heat stress. The gene-set enrichment analysis revealed functional terms related to fertilization, developmental biology, heat shock proteins and oxidative stress, among others. Overall, our findings contribute to a better understanding of the genetics underlying the reproductive performance of dairy cattle under heat stress conditions and point out novel genomic strategies for improving thermotolerance and fertility via marker-assisted breeding.  相似文献   
57.
1.  The Trivers–Willard model of optimal sex ratios predicts that in polygynous species mothers in better condition should produce more male than female offspring. However, empirical support for this hypothesis in mammals and especially ungulates has been equivocal. This may be because the fitness of mothers has been defined in different ways, reflecting morphological, physiological or behavioural measures of condition. In addition, factors other than maternal condition can influence a mother's fitness. Given that recent studies of wild ungulates have demonstrated the importance of the timing of conception and birth on offspring fitness, litters conceived at different stages of the rut might be expected to exhibit differences in types and embryonic sex ratio.
2.  Based on a 6-year survey of the reproductive tracts of female moose harvested in Estonia, we investigated the effect of conception date on the types of litters produced and on the foetal sex ratio.
3.  There was a clear relationship between conception date and litter characteristics. Overall, earlier conceived litters were more likely than those conceived late to contain multiple embryos and a high proportion of males. However, while foetal sex ratio varied nonlinearly with conception date in yearlings and subadults, no relationship was found in adults.
4.  We conclude that female moose adjust foetal sex ratio and litter type/size depending on their age and the date of conception, and that these adjustments are in accordance with the Trivers–Willard hypothesis if females that conceive earlier are in better condition.  相似文献   
58.
Existing empirical research often do not explain which concepts about genetics underlie the assumption that genetic information is deemed important for donor-conceived offspring. This study focused on how donor-conceived individuals following anonymous sperm donation give meaning to and make sense of genes and genetics. Analysis is based on focus groups and interviews with adult donor-conceived offspring. Findings suggest that genes are part of their specific context of being donor-conceived but also play a role in daily life. Genes make sense on an individual level and a relational level, both on parent-child as sibling-level. On an individual level they were perceived as (1) a biological starting package, (2) their own unique combination and (3) as a reference point. On a relational level, genes were seen as (1) “person-al”, (2) connecting and (3) locating individuals. This information is essential for those supporting/counseling donor conceived offspring and families as well as for policy-members.  相似文献   
59.
The role of social cues in the reproduction of social mammals, particularly carnivores, has been thoroughly studied and documented in literature. However, environmental cues such as resources of water, food, and shelter have been identified to a lesser extent. Pregnant lions (Panthera leo) are notoriously secretive during the final stages of pregnancy and postpartum. Behavioral indicators depicted by movement patterns obtained by remote detection of collared female lions in the Kruger National Park were necessary for the monitoring of birth timing. Over the study period, eight plus a potential three parturition incidences of collared females were recorded. Of the variables measured (step length, range size, duration, prey biomass, and rainfall), range size during the month of parturition was the most indicative movement pattern of a successful birth. By backdating the potential birth month of the litters, date of conception was calculated and our results revealed a correlation between the birthing peaks of preferred prey during the month of conception. Birth timing in conjunction with remote sensing and ecological factors were thus identified behaviors associated with denning.  相似文献   
60.
A probability distribution for the number of conceptions during a specified period of time is derived assuming that the fecundability as well as the proportion of incomplete conceptions vary between conceptions. A procedure for finding the estimate of some of the parameters has been outlined. The probability model was tested with the date from the Varnasi survey.  相似文献   
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