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1.
The nonreproductive role of religious women in the European Middle Ages presents the ideal forum for the discussion of elite family strategies within a historical context. I apply the evolutionary concept of kin selection to this group of women in order to explain how a social formation in which religious women failed to reproduce benefited medieval noble lineages. After a brief review of the roles of noble women in the later Middle Ages, I identify two benefits that nonreproductive women provided within a patrilineal inheritance system. First, spatial segregation and Christian ideology together served to curtail the production of offspring who could pose a threat to lineage interests. Second, cloistered noble women served as a strong political and economic bloc that could further lineage interests within a religious context. Finally, I discuss the evolutionary basis for the formation of groups of nonreproductive women. Using the foundation provided by animal behavioral studies, I apply the twin concepts of cooperative breeding and parental manipulation to noble lineages of the medieval period. The comments of Jim Boone, Jeffrey Dickemann, Bob Leonard, Lance Lundquist, Randy Thornhill, and one anonymous reviewer have greatly contributed to the improvement of this paper. Erica Hill is a Ph.D. candidate in anthropology at the University of New Mexico. She is an archaeologist with multidisciplinary interests in the study of ethnohistory, gender, and anthropological theory.  相似文献   

2.
Plants Used for Reproductive Health by Nahua Women in Northern Veracruz, Mexico. This paper reports the use of medicinal plants by Nahua women in the state of Veracruz, Mexico. It documents the women’s plant knowledge for reproductive purposes, which includes uses such as conception, pregnancy, birth, contraception, menstruation, post-partum, and general reproductive health. The concept of equilibrium is very important in regaining health among the Nahua; consequently, many of the medicinal plants have this as their primary purpose. The introduction of biomedical clinics and hospitals in the region has had a significant effect on the loss of knowledge about medicinal plants. Additionally, the midwives are not taking any new apprentices and laywomen are not passing on their knowledge to future generations. This generational gap contributes to the loss of knowledge about medicinal plants. This research contributes to the study of indigenous ethnobotany by (a) creating a record of the plant knowledge possessed by indigenous women, (b) giving voice to some of their health concerns, (c) indicating how the introduction of biomedicine has affected their plant use, and (d) providing a framework for understanding how marginal peoples around the world respond to the impact that globalization and change has on their health needs and local ethnobotanical knowledge.  相似文献   

3.
The determinants of the geographic distribution of avian hematozoa are poorly understood. Sampling parasites from one avian host species across a wide geographic range is an accepted approach to separate the potential influence of host species distribution from geographic effects not directly related to host species biology. We used polymerase chain reaction to screen samples for hematozoan infection from 490 house finches (Carpodacus mexicanus) collected at 8 sites spanning continental North America. To explore geographic patterns of parasite lineage distributions, we sequenced a portion of the mitochondrial cytochrome b gene of Plasmodium species infecting 77 house finches. We identified 5 distinct Plasmodium haplotypes representing 3 lineages that likely represent 3 species. One lineage was common at all sites where we detected Plasmodium species. The second lineage contained 3 haplotypes that showed phylogeographic structuring on a continent-wide scale, with 1 haplotype common in eastern North America and 2 common in western North America. The third divergent lineage was recovered from 1 individual host. Considered together, the partial phylogeographic structuring of Plasmodium cytochrome b lineages over the range of the house finch suggests that parasite lineage distribution is not solely dependent on host species distribution, and other factors such as arthropod vector competence and distribution may be important.  相似文献   

4.
A combined data set of DNA sequences (6021 bp) from five protein-coding genes of the chloroplast genome (rbcL, atpB, psaA, psaB, and psbC genes) were analyzed for 42 strains representing 30 species of the colonial Volvocales (Volvox and its relatives) and 5 related species of green algae to deduce robust phylogenetic relationships within the colonial green flagellates. The 4-celled family Tetrabaenaceae was robustly resolved as the most basal group within the colonial Volvocales. The sequence data also suggested that all five volvocacean genera with 32 or more cells in a vegetative colony (all four of the anisogamous/oogamous genera, Eudorina, Platydorina, Pleodorina, and Volvox, plus the isogamous genus Yamagishiella) constituted a large monophyletic group, in which 2 Pleodorina species were positioned distally to 3 species of Volvox. Therefore, most of the evolution of the colonial Volvocales appears to constitute a gradual progression in colonial complexity and in types of sexual reproduction, as in the traditional volvocine lineage hypothesis, although reverse evolution must be considered for the origin of certain species of Pleodorina. Data presented here also provide robust support for a monophyletic family Goniaceae consisting of two genera: Gonium and Astrephomene.  相似文献   

5.
J. S. Furnivall's characterization of Java in the last half‐century of colonial rule as a ‘plural society’ has largely been taken for granted by most scholars who have supported or opposed the applicability of the concept in a Caribbean or African context. In the ‘plural society’ of colonial Java, according to Furnivall, Europeans, Chinese and natives each held by their own religion, their own culture and language, meeting as individuals only in the market place. This article re‐examines the case of colonial Java, which first prompted Furnivall to use the concept, paying particular attention to the Chinese. It argues that at the time he invented the term, he exaggerated the ‘pluralistic’ features of colonial society, and that, when applied to the situation at the turn of the century, the concept was quite misleading. Rather, it is suggested, colonial society in the urban centres of Java at that time might in many respects just as well be characterized as a ‘mestizo society’.  相似文献   

6.
A Sensory Ecology of Medicinal Plant Therapy in Two Amazonian Societies   总被引:3,自引:0,他引:3  
Sensory anthropology has explored sensation as a fruitful but poorly examined domain of cross-cultural research. Curiously, sensory anthropologists have mostly ignored scientific research into sensation, even that which addresses cross-cultural variation. A comparative study in two Amazonian societies (Matsigenka, Yora [Nahua]) documented the role of the senses in medicinal plant therapy and benefited greatly from theoretical insights gleaned from sensory science. The study reveals a complex interweaving of cultural and ecological factors in medicinal plant selection, with sensation standing at the culture--nature nexus linking medical ideas with medical materials. By synthesizing (rather than antagonizing) scientific and anthropological insights, sensation can be understood as a biocultural phenomenon rooted in human physiology yet constructed through individual experience and culture. Overcoming the limitations of a narrowly defined sensory anthropology, sensory ecology is here proposed as a new theoretical perspective for addressing human--environment interactions mediated by the senses.  相似文献   

7.
H. J. Hoops 《Protoplasma》1997,199(3-4):99-112
Summary The colonial Volvocales are often said to be composed of Chlamydomonas-like cells, but there are substantial differences in motility and flagellar apparatus construction between the unicellular forms and the individual members of a colony or spheroid. These changes appear to be required for effective organismal motion and might possibly limit the rate at which new colonial forms evolve from unicellular ones. The flagellar-beat envelopes in colonial members are modified such that they beat in the same direction and in parallel planes with their effective strokes at right angles to the cellular anterior-posterior axis. These changes result from a series of developmental events of the flagellar apparatus of the colonial forms while the colony is still an embryo. Differences in the flagellar-apparatus structure in the members of the Goniaceae and Volvocaceae are not obviously correlated with the traditional placement of these algae in a simple volvocine lineage. Effective colonial motion clearly requires precise positioning and rotational orientation of the cells within the colony. Almost any arrangement where the cells are placed with rotational symmetry within the colony results in colonial progression with rotation. Such rotational symmetry is present from the time of embryogenesis. The mechanism that leads to organismal steering in behavioral responses (e.g., phototaxis) must likewise differ between colonial and unicellular forms. In at least some cases, this appears to result from changes in beat frequency in some parts of the spheroid, but changes in beat direction cannot be ruled out for all forms.  相似文献   

8.
9.
The genetic structure of eight Mus musculus L. populations in Primorskii krai was studied with the use of taxon-specific markers of different inheritance systems: nDNA (RAPD), mtDNA (D-loop), and chromosomes. The results obtained demonstrate that although the compared nuclear marker characteristics (nDNA and chromosomes) have the same basis they are not linke with each other and, moreover, are often mutually inconsistent. Discordance in the inheritance of the marker characteristics in most of the animals studied is a result of extensive hybridization involving two to four house mouse subspecies. To identify taxon-specific nuclear markers revealed by RAPD, they were cloned and sequenced, and their localization on chromosomes was determined. It was found that some fragments similar in size consist of two different comigrating sequences that are localized on different chromosomes and belong to different subspecies. All sequenced anonymous markers are localized in protein-coding genes. The functions of genes containing the marker sequences have been established. Differences in the taxon-specific RAPD fragments are associated with changes in the structure of important functional genes, and this can be considered as a significant genetic marker.  相似文献   

10.
The genetic structure of eight Mus musculus L. populations in Primorskii krai was studied with the use of taxon-specific markers of different inheritance systems: nDNA (RAPD), mtDNA (D-loop), and chromosomes. The results obtained demonstrate that although the compared nuclear marker characteristics (nDNA and chromosomes) have the same basis they are not linke with each other and, moreover, are often mutually inconsistent. Discordance in the inheritance of the marker characteristics in most of the animals studied is a result of extensive hybridization involving two to four house mouse subspecies. To identify taxonspecific nuclear markers revealed by RAPD, some RAPD PCR products were cloned, and their localization on chromosomes was determined. It was found that some fragments similar in size consist of two different comigrating sequences that are localized on different chromosomes and belong to different subspecies. All sequenced anonymous markers are localized in protein-coding genes. The functions of genes containing the marker sequences have been established. Differences in the taxon-specific RAPD fragments are associated with changes in the structure of important functional genes, and this can be considered as a significant genetic marker.  相似文献   

11.
Molecular phylogeny of the volvocine flagellates.   总被引:8,自引:0,他引:8  
Phylogenetic studies of approximately 2,000 bases of sequence from the large and small nuclear-encoded ribosomal RNAs are used to investigate the origins of the genus Volvox. The colonial and multicellular genera currently placed in the family Volvocaceae form a monophyletic group that is significantly closer phylogenetically to Chlamydomonas reinhardtii than it is to the other unicellular green flagellates that were tested, including Chlamydomonas eugametos, Chlorella pyrenoidosa, and Haematococcus lacustris. Statistical analysis of 251 phylogenetically informative nucleotide positions rejects the "volvocine lineage" hypothesis, which postulates a monophyletic evolutionary progression from unicellular organisms (such as Chlamydomonas), through colonial organisms (e.g., Gonium, Pandorina, Eudorina, and Pleodorina) demonstrating increasing size, cell number, and tendency toward cellular differentiation, to multicellular organisms having fully differentiated somatic and reproductive cells (in the genus Volvox). The genus Volvox appears not to be monophyletic. Volvox capensis falls outside a lineage containing other representatives of Volvox (V. aureus, V. carteri, and V. obversus), and both of these Volvox lineages are more closely related to certain colonial genera than they are to each other. This implies either a diphyletic origin of Volvox from different colonial volvocacean ancestors, a phylogenetic derivation of some of the colonial genera from a multicellular (i.e., Volvox) ancestor, or both. Considered together with previously published observations, these results suggest that the different levels of organizational and developmental complexity found in the Volvocaceae represent alternative stable states, among which evolutionary transitions have occurred several times during the phylogenetic history of this group.  相似文献   

12.

Objectives

The aim of this study was to test the hypothesis that ethnic and ethnolinguistic discrimination, and Post-Traumatic Stress Disorder (PTSD) related to being Indigenous as well as different aspects of acculturative stress, are associated with poorer health and higher levels of depression among the Nahua Indigenous communities.

Materials and methods

Our quantitative survey was carried out in four different regions inhabited by the Nahua people in Mexico. Self-rated health and depression, the symptoms of PTSD, two facets of acculturative stress and ethnolinguistic discrimination were assessed by questionnaires. The data were analyzed using binary logistic regression models.

Results

The symptoms of PTSD and acculturative stress experienced in the workplace were significantly associated with a higher risk of poor self-rated health, adjusted for various socio-demographic characteristics. Acculturative stress, discouragement of language use, language avoidance and ethnolinguistic discrimination were related to a higher risk of depression and PTSD.

Discussion

Our research implies that ethnic and linguistic discrimination, acculturative stress and the memory of harm linked to being Indigenous reflected in the symptoms of PTSD, are important predictors of poorer health and depression among Nahua groups in Mexico. These adverse effects could be significantly counteracted by effective dealing with stigmatization and discrimination against Indigenous people in Mexico and by replacing strong assimilation pressures with integrational approaches that respect ethnolinguistic diversity and reduce socioeconomic marginalization.  相似文献   

13.
The molecular events triggered by MHC recognition and how they lead to the emergence of mature CD4 and CD8 lineage thymocytes are not yet understood. To address these questions, we have examined what signals are necessary to drive the development of CD8 lineage thymocytes in TCRalpha(-) mice in which TCR/MHC engagement cannot occur. We find that the combination of constitutive Notch activity and constitutive Bcl-2 expression are necessary and sufficient to allow the appearance of mature CD8 lineage thymocytes in TCRalpha(-) mice. In addition, Notch activity alone in TCRalpha(-) mice can induce the up-regulation of HES1, suggesting that thymocytes are competent to respond to Notch signaling in the absence of MHC recognition. These data indicate that survival and lineage commitment represent distinct, parallel pathways that occur as a consequence of MHC recognition, both of which are necessary for the development of mature CD8 lineage T cells.  相似文献   

14.
This paper reassesses Robert Koch's work on tropical infections of humans and cattle as being inspired by an underlying interest in epidemiology. Such an interest was developed from the early 1890s when it became clear that an exclusive focus on pathogens was insufficient as an approach to explain the genesis and dynamics of epidemics. Koch, who had failed to do so before, now highlighted differences between infection and disease and described the role of various sub-clinical states of disease in the propagation and--consequently--in the control of epidemics. Studying pathologies of men and cattle in tropical countries eventually facilitated the application of such measures in Europe through the screening of healthy carriers of typhoid, which was carried out in 1902. The concept of the carrier state can be understood as a spin-off from tropical medicine into the study and control of infectious disease in Europe. With it travelled assumptions that were typical for colonial and veterinary medicine where the health of indigenous individuals or cattle would be a secondary objective compared to the control of diseases in populations.  相似文献   

15.
Recent work on inheritance systems can be divided into inclusive conceptions, according to which genetic and non-genetic inheritance are both involved in the development and transmission of nearly all animal behavioral traits, and more demanding conceptions of what it takes for non-genetic resources involved in development to qualify as a distinct inheritance system. It might be thought that, if a more stringent conception is adopted, homologies could not subsist across two distinct inheritance systems. Indeed, it is commonly assumed that homology relations cannot survive a shift between genetic and cultural inheritance systems, and substantial reliance has been placed on that assumption in debates over the phylogenetic origins of hominin behavioral traits, such as male-initiated intergroup aggression. However, in the homology literature it is widely accepted that a trait can be homologous—that is, inherited continuously in two different lineages from a single common ancestor—despite divergence in the mechanisms involved in the trait’s development in the two lineages. In this paper, we argue that even on an extremely stringent understanding of what it takes for developmental resources to form a separate inheritance system, homologies can nonetheless subsist across shifts between distinct inheritance systems. We argue that this result is a merit of this way of characterizing what it is to be an inheritance system, that it has implications for adjudicating between alternative accounts of homology, and that it offers an important cautionary lesson about how (not) to reason with the homology concept, particularly in the context of cultural species.  相似文献   

16.
It is widely held that organelles inherit from the maternal lineage. However, the plastid genome in quite a few angiosperms appears to be biparentally transmitted. It is unclear how and why biparental inheritance of the genome became activated. Here, we detected widespread occurrence of plastids in the sperm cells (a cellular prerequisite for biparental inheritance) of traditional Caprifoliaceae. Of the 12 genera sampled, the sperm cells of Abelia, Dipelta, Heptacodium, Kolkwitzia, Leycesteria, Linnaea, Lonicera, Symphoricarpos, Triosteum and Weigela possessed inheritable plastids. The other genera, Sambucus and Viburnum, lacked plastids in sperm cells. Interestingly, such exclusion of plastids in the sperm cells of some Caprifoliaceae appeared to be associated with the divergence of Dipsacales phylogeny. Closer examination of Weigela florida revealed that both plastids and plastid DNA were highly duplicated in the generative cells. This implies that the appearance of plastids in sperm cells involved cellular mechanisms. Because such mechanisms must enhance the strength of plastid transmission through the paternal lineage and appear ubiquitous in species exhibiting biparental or potential biparental plastid inheritance, we presume that biparental plastid genetics may be a derived trait in angiosperms. This is consistent with our extended phylogenetic analysis using species with recently discovered modes of potential plastid inheritance. The results show that basal and early angiosperms have maternal plastid transmission, whereas all potential biparental transmission occurs at terminal branches of the tree. Thus, unlike previous studies, we suggest that biparental plastid inheritance in angiosperms was unilaterally converted from the maternal transmission mode during late angiosperm evolution.  相似文献   

17.
The afro-alpine region comprises the high mountains of Ethiopia and tropical East Africa, which represent biological 'sky islands' with high level of endemism. However, some primarily arctic-alpine plants also occur in the afro-alpine mountains. It has been suggested that these plants are Tertiary relicts, but a recent worldwide study of Arabis alpina suggests that this species colonized the region twice during the Pleistocene. Here we investigate the detailed colonization history of A. alpina in the afro-alpine region based on chloroplast DNA sequences from 11 mountain systems. The results confirm the twice-into-Africa scenario. The Asian lineage is confined to the mountains closest to the Arabian Peninsula, on opposite sides of the Rift Valley (Simen Mts and Gara Muleta in Ethiopia), suggesting long-distance dispersal of this lineage. The African lineage is divided into two phylogeographic groups with distinct geographic distribution. The observed pattern is consistent with isolation of the African lineage in at least two interglacial refugia, located on separated highlands, followed by range expansion in cooler period(s), when the afro-alpine habitat extended further down the mountains. Several long-distance dispersal events, also across the Rift Valley, are suggested by single haplotypes observed outside the area occupied by the phylogeographic groups they belonged to.  相似文献   

18.
19.
Evolution of solitary or colonial life histories in tunicates is accompanied by dramatic developmental changes that affect morphology and reproduction. We compared vasa expression in a solitary ascidian and a closely related colonial ascidian, in an effort to uncover developmental mechanisms important during the evolution of these contrasting life histories, including the ability to reproduce by budding. In this study, we explored the origin of germ cells in new buds developing by asexual reproduction in a colonial ascidian, Botrylloides violaceus and compared it to the source of germ cells in a solitary ascidian Boltenia villosa. We studied expression by in situ hybridization of vasa, a DEAD box RNA helicase gene found in germ cells across the metazoans. In B. villosa, bv-vasa mRNA was expressed in putative germ cells and oocytes of adult gonads, and was sequestered into a posterior lineage during embryogenesis. In mature colonies of the ascidian B. violaceus, bot-vasa mRNA was expressed in putative spermatogonia, in oocytes of zooids, and in some circulating cells in the zooids and differentiating buds. We propose that expression of vasa in cells other than gonadal germ cells of zooids in a colonial ascidian may serve as a source of germ-line stem cells in the colony.  相似文献   

20.
Simian immunodeficiency virus of chimpanzees (SIVcpz) has a significant negative impact on the health, reproduction, and life span of chimpanzees, yet the prevalence and distribution of this virus in wild-living populations are still only poorly understood. Here, we show that savanna chimpanzees, who live in ecologically marginal habitats at 10- to 50-fold lower population densities than forest chimpanzees, can be infected with SIVcpz at high prevalence rates. Fecal samples were collected from nonhabituated eastern chimpanzees (Pan troglodytes schweinfurthii) in the Issa Valley (n = 375) and Shangwa River (n = 6) areas of the Masito-Ugalla region in western Tanzania, genotyped to determine the number of sampled individuals, and tested for SIVcpz-specific antibodies and nucleic acids. None of 5 Shangwa River apes tested positive for SIVcpz; however, 21 of 67 Issa Valley chimpanzees were SIVcpz infected, indicating a prevalence rate of 31% (95% confidence interval, 21% to 44%). Two individuals became infected during the 14-month observation period, documenting continuing virus spread in this community. To characterize the newly identified SIVcpz strains, partial and full-length viral sequences were amplified from fecal RNA of 10 infected chimpanzees. Phylogenetic analyses showed that the Ugalla viruses formed a monophyletic lineage most closely related to viruses endemic in Gombe National Park, also located in Tanzania, indicating a connection between these now separated communities at some time in the past. These findings document that SIVcpz is more widespread in Tanzania than previously thought and that even very low-density chimpanzee populations can be infected with SIVcpz at high prevalence rates. Determining whether savanna chimpanzees, who face much more extreme environmental conditions than forest chimpanzees, are more susceptible to SIVcpz-associated morbidity and mortality will have important scientific and conservation implications.  相似文献   

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