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Results for “Cultural Evolution”

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At least 523 records · Page 29Linked to original sources
PubMed2004

Effect of captivity on genetic variance for five traits in the large milkweed bug (Oncopeltus fasciatus).

Understanding the changes in genetic variance which may occur as populations move from nature into captivity has been considered important when populations in captivity are used as models of wild ones. However, the inherent significance of these changes has not previously been appreciated in a conservation context: are the methods aimed at founding captive populations with gene diversity representative of natural populations likely also to capture representative quantitative genetic variation? Here, I investigate changes in heritability and a less traditional measure, evolvability, between nature and captivity for the large milkweed bug, Oncopeltus fasciatus, to address this question. Founders were collected from a 100-km transect across the north-eastern US, and five traits (wing colour, pronotum colour, wing length, early fecundity and later fecundity) were recorded for founders and for their offspring during two generations in captivity. Analyses reveal significant heritable variation for some life history and morphological traits in both environments, with comparable absolute levels of evolvability across all traits (0-30%). Randomization tests show that while changes in heritability and total phenotypic variance were highly variable, additive genetic variance and evolvability remained stable across the environmental transition in the three morphological traits (changing 1-2% or less), while they declined significantly in the two life-history traits (5-8%). Although it is unclear whether the declines were due to selection or gene-by-environment interactions (or both), such declines do not appear inevitable: captive populations with small numbers of founders may contain substantial amounts of the evolvability found in nature, at least for some traits.

Animal Husbandry↗
PubMed2005

[Menstruation in the systemic context. New questions -- questionable connections].

Experiencing and the significance of menstruation could possibly be a decisive factor in your physiology or pathologic physiology, in accordance with blood flow disturbance or endometriosis. Menstruation is a systemic, characteristic experience. Evolution, family, culture, community, media, health service and even the economy have an influence on the "period system". Damage and use, sense and the nonsensical of regular bleeding stand to the test. The cycle comes under increasing "pressure" and is no longer in "rhythm". Counter regulation, through regulation of the period seems to prevent the personal, community and health-wise restrictions. The price for this is unknown. Clearly, there is no longer a path between a natural, relaxed acceptance of and an artificial abolition of blood flow. The question of direction is posed in the menarche. This question remains unanswered even in our time.

Attitude to Health↗
PubMed2004

Evolutionarily conserved sequence elements that positively regulate IFN-gamma expression in T cells.

Our understanding of mechanisms by which the expression of IFN-gamma is regulated is limited. Herein, we identify two evolutionarily conserved noncoding sequence elements (IFNgCNS1 and IFNg CNS2) located approximately 5 kb upstream and approximately 18 kb downstream of the initiation codon of the murine Ifng gene. When linked to the murine Ifng gene (-3.4 to +5.6 kb) and transiently transfected into EL-4 cells, these elements clearly enhanced IFN-gamma expression in response to ionomycin and phorbol 12-myristate 13-acetate and weakly enhanced expression in response to T-bet. A DNase I hypersensitive site and extragenic transcripts at IFNgCNS2 correlated positively with the capacity of primary T cell subsets to produce IFN-gamma. Transcriptionally favorable histone modifications in the Ifng promoter, intronic regions, IFNgCNS2, and, although less pronounced, IFNgCNS1 increased as naïve T cells differentiated into IFN-gamma-producing effector CD8+ and T helper (TH) 1 T cells, but not into TH2 T cells. Like IFN-gamma expression, these histone modifications were T-bet-dependent in CD4+ cells, but not CD8+ T cells. These findings define two distal regulatory elements associated with T cell subset-specific IFN-gamma expression.

Animals↗
PubMed2004

Environment, agriculture, and settlement patterns in a marginal Polynesian landscape.

Beginning ca. A.D. 1400, Polynesian farmers established permanent settlements along the arid southern flank of Haleakala Volcano, Maui, Hawaiian Islands; peak population density (43-57 persons per km(2)) was achieved by A.D. 1700-1800, and it was followed by the devastating effects of European contact. This settlement, based on dryland agriculture with sweet potato as a main crop, is represented by >3,000 archaeological features investigated to date. Geological and environmental factors are the most important influence on Polynesian farming and settlement practices in an agriculturally marginal landscape. Interactions between lava flows, whose ages range from 3,000 to 226,000 years, and differences in rainfall create an environmental mosaic that constrained precontact Polynesian farming practices to a zone defined by aridity at low elevation and depleted soil nutrients at high elevation. Within this productive zone, however, large-scale agriculture was concentrated on older, tephra-blanketed lava flows; younger flows were reserved for residential sites, small ritual gardens, and agricultural temples.

Agriculture↗
PubMed2001

Genetic evidence for different male and female roles during cultural transitions in the British Isles.

Human history is punctuated by periods of rapid cultural change. Although archeologists have developed a range of models to describe cultural transitions, in most real examples we do not know whether the processes involved the movement of people or the movement of culture only. With a series of relatively well defined cultural transitions, the British Isles present an ideal opportunity to assess the demographic context of cultural change. Important transitions after the first Paleolithic settlements include the Neolithic, the development of Iron Age cultures, and various historical invasions from continental Europe. Here we show that patterns of Y-chromosome variation indicate that the Neolithic and Iron Age transitions in the British Isles occurred without large-scale male movements. The more recent invasions from Scandinavia, on the other hand, appear to have left a significant paternal genetic legacy. In contrast, patterns of mtDNA and X-chromosome variation indicate that one or more of these pre-Anglo-Saxon cultural revolutions had a major effect on the maternal genetic heritage of the British Isles.

Cultural Evolution↗
PubMed1972

The upper temperature limit for eukaryotic organisms.

An upper temperature limit near 60 degrees for eukaryotic organisms is documented by results of a systematic search for fungi able to grow at higher temperatures. Samples from hot springs, thermal soils, self-heating coal waste piles, and other natural and man-made heated habitats did not yield fungi when enrichments were done at 62 degrees , whereas fungi able to grow at 55-60 degrees can be readily isolated from such habitats. Earlier work had shown that eukaryotic algae are also absent from environments with temperatures above 55-60 degrees . It is suggested that the failure of eukaryotes to evolve members able to grow at higher temperatures is due to their inability to form organellar membranes that are both thermostable and functional.

Biological Evolution↗
PubMed1995

Genetics and the origin of European languages.

A new set of European genetic data has been analyzed to dissect independent patterns of geographic variation. The most important cause of European genetic variation has been confirmed to correspond to the migration of Neolithic farmers from the area of origin of agriculture in the Middle East. The next most important component of genetic variation is apparently associated with a north-south gradient possibly due to adaptation to cold climates but also to the differentiation of the Uralic and the Indo-European language-speaking people; however, the relevant correlations are not significantly different from zero after elimination of the spatial autocorrelation. The third component is highly correlated with the infiltration of the Yamna ("Kurgan") people, nomadic pastoralists who domesticated the horse and who have been claimed to have spread Indo-European languages to Europe; this association, which is statistically significant even when taking spatial autocorrelations into account, does not completely exclude the hypothesis of Indo-European as the language of Neolithic farmers. It is possible that both expansions were responsible for the spread of different subfamilies of Indo-European languages, but our genetic data cannot resolve their relative importance.

Alleles↗
PubMed1994

Exploring the self-concept in an African culture.

Self-concept orientations (individualistic, collectivistic, and moralistic) were examined for 210 Zimbabwe college students of a Shona cultural background. Although the students tended to endorse an individualistic self-concept orientation to a significant extent, the women and the older students were more inclined to perceive of the self-concept as collectivistic and moralistic in orientation. Implications for self-concept models for African cultures and suggestions for further research are discussed.

Adult↗
PubMed1975

The fall of man.

Explore the source record for details and available documents.

Anthropology↗
PubMed2004

Therapeutic communities: a therapeutic bridge.

The original therapeutic community movement has seen a variety of interpretations that may bear little resemblance to the original model. The democratic model concept of social learning offers one approach to further social maturation and personality change. The programmatic or concept model offers another approach based on a behavior code and behavioral concepts. Both of these communities are human groups and appear to share the hereditary behavior of such groups. A Darwinian approach is used to facilitate understanding of both communities. A generic biosocial therapeutic community is described.

Cultural Evolution↗
PubMedDate not supplied

William Penn and the peace of Europe.

The Quaker William Penn proposed a European Union to ensure peace in the continent in 1693. Penn was unusual among Quakers in being of the landed upper classes. When converted, he became a leader of the Quakers and other Dissenters. He had the two related ideals of peace and religious toleration, and dreamed of realizing both ideals in the New World. A practical idealist, he took advantage of four factors: friends at Court made through his social position; King Charles II's gratitude for services rendered by his father, Admiral Sir William Penn; the King's desire to conciliate the City merchants, who were ready to invest in Penn's scheme; and above all the King's concern to get North America settled by British colonists. Penn received a charter to found Pennsylvania in 1681. In England he worked hard, especially in collaboration with James II, for toleration for the cruelly persecuted Quakers and other Dissenters. In Pennsylvania he was able to establish complete toleration and his fair and friendly treatment gave the colony 70 years of peaceful co-existence with the Indians. In his essay on the peace of Europe, he virtually invented collective security and with amazing foresight planned in detail something very like the present European Union.

Christianity↗