[Breast-feeding during the process of transculturation].
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Adult↗
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Results for “Cultural Evolution”
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A dialectical view of creativity.
This paper draws into alignment two time-honored psychoanalytic concepts which are addressed in diametrically different ways to the question of human origins. These are the family romance and the primal scene. Traditionally these terms have not been seen as related to each other, and while properly understood as opposites they may also be seen as complementary. Creativity offers the ideal area for certain connections to be examined. As a revision of origins by means of casting oneself as an orphan and adding another set of lofty , Olympian -style parents, the family romance also revises for the individual the critical sexual act which brought him into existence, the primal scene. It is this act of our animal heritage, from which the child is the excluded party, that also disturbingly reveals the parents in their necessarily lowly actions . Thus Freud's three-part formula can be invoked and implemented: the painful reality from which the artist turns is preeminently a primal scene; the fantasy ( daydream ) of choice to which he turns is the family romance . By working through certain accompanying, often cultural illusions, the artist finds his way back to reality, which often amounts to a corrected apprehension of the Primal Scene , archetypally the Sphinx 's riddle, the answer to which is adult sexuality and an important step toward ego-identity. Between the subjective pole of the family romance and the objective pole of the primal scene the artist's work develops. Properly specified, the two concepts serve as important organizers and regulators of creativity. In order to place creativity within a cultural context, I have examined two areas beyond the perimeters of art. Both in the psychotic condition of Schreber and in the tribal condition of the Dogon , the family romance and the primal scene exist in overlapping or undifferentiated states. I have hypothesized that in no small part the evolution of culture depends on mankind's understanding himself by learning to distinguish between supernatural and natural explanations of origins. The individual also faces the task of sorting out subjective and fanciful notions of his origin from objective and perceptual accounts. In this process he may wander afield and end up concocting his own personal mythology. The artist concentrates the subjective and objective aspects of origins around the poles of the family romance and the primal scene . In this he is not unique. But he draws on mythic and cultural traditions in such imaginative ways as to represent his fantasies indirectly and in such symbolic modes as can be most widely shared.
Adult↗
Systematic changes in gene expression patterns following adaptive evolution in yeast.
Culturing a population of Saccharomyces cerevisiae for many generations under conditions to which it is not optimally adapted selects for fitter genetic variants. This simple experimental design provides a tractable model of adaptive evolution under natural selection. Beginning with a clonal, founding population, independently evolved strains were obtained from three independent cultures after continuous aerobic growth in glucose-limited chemostats for more than 250 generations. DNA microarrays were used to compare genome-wide patterns of gene expression in the evolved strains and the parental strain. Several hundred genes were found to have significantly altered expression in the evolved strains. Many of these genes showed similar alterations in their expression in all three evolved strains. Genes with altered expression in the three evolved strains included genes involved in glycolysis, the tricarboxylic acid cycle, oxidative phosphorylation, and metabolite transport. These results are consistent with physiological observations and indicate that increased fitness is acquired by altering regulation of central metabolism such that less glucose is fermented and more glucose is completely oxidized.
Adaptation, Physiological↗
Medical Ethics: Evolution, Rights and the Physician, by Henry A. Shenkin.
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Altruism↗
The CO2-concentrating mechanism in the physiological context: lowering the CO2 supply diminishes culture growth and economises starch utilisation in Chlamydomonas reinhardtii.
In a synchronously grown Chlamydomonas reinhardtii (Chlorophyceae) culture the CO2-concentrating mechanism (CCM) was induced by lowering the CO2 level from 4% to 0.036% CO2 (culture HL). The effects of the reduced carbon supply on starch levels were studied over a period of up to 100 h and compared with control cultures kept either at 4% CO2 (culture H) or continuously at ambient air (0.036% CO2, culture L). Lowering the CO2 supply reduced culture growth as estimated by chlorophyll, protein and cell density. The starch level continued to show diurnal variations with an initially reduced rate of starch synthesis at reduced or abolished culture growth. Subsequently, starch maxima and minima increased. After 4 days the resulting pattern for culture HL was similar to that of culture L, which possessed higher minima but identical maxima to culture H. The intracellular starch localisation was examined on electron micrographs. Cell extracts were assayed for ADP-glucose pyrophosphorylase (EC 2.7.7.27) and starch phosphorylase (EC 2.4.1.1) activities. Over the assayed period of 2 days, there was a good correlation between the observed changes in the starch levels and the measured enzyme activities. The rate of CO2-dependent oxygen evolution of culture HL declined from 100% to 60% of the control over the day. This indicates that the diminished or abolished growth and the impairment of starch accumulation upon CO2 depletion are not simply consequences of the lowered level of the substrate CO2. The diminished growth and the peculiar starch accumulation pattern with higher positions of the starch minima in low-CO2 cells are interpreted as economised starch utilisation as long-term aspects of induction of the CCM.
Animals↗
Lactate dehydrogenase (LDH) activity of the cultured eukaryotic cells as marker of the number of dead cells in the medium [corrected].
One significant problem in monitoring a culture's evolution is to assess change in cell viability. We have demonstrated that LDH release could be a good indicator of cellular damage of many cell lines, especially during shear stress or sonication. Moreover, we have found a significant correlation between the number of dead cells, determined by Trypan Blue staining, and LDH activity measurements in the supernatant of hybridoma strains, whatever the culture conditions. We have also shown that when viability is still near 100% no LDH is released even at high cell concentrations. Therefore, LDH should serve as a potential marker of cell injury and death.
Animals↗
The animal cultures debate.
Recent interest in animal cultures has been fuelled by high-profile reports of intra- and interpopulation differences in the behavioural repertoires of primates and cetaceans, consistent with the existence of socially learned traditions. Several studies have mapped spatial differences in behaviour, revealing a mosaic of behavioural phenotypes within species. The dominant current approach attempts to determine whether this is cultural variation by excluding asocial learning, ecological or genetic factors. However, claims of animal cultures remain controversial because such comparisons are subject to weaknesses; thus, new approaches to isolating the influence of culture on behaviour are required. Here we suggest that, rather than attributing behaviour to explanatory categories, researchers would often be better advised to partition variance in behaviour to alternative sources.
Animal Communication↗
Evolutionary psychology: toward a unifying theory and a hybrid science.
Although evolutionary psychology is typically associated with "selfish gene theory," numerous other approaches to the study of mind and behavior provide a wealth of concepts for theorizing about psychology, culture, and development. These include general evolutionary approaches and theories focused on sociality, dual inheritance, multilevel selection, and developmental systems. Most evolutionary accounts use the same methods as Darwin-the "fit among facts"-to use natural selection as an explanation for behavior. Scientific standards for constraining and evaluating such accounts, research into the mutual influence of science and society on the understanding of evolution, and computational technologies for modeling species-typical processes are important considerations. Coevolutionary theories and developmental systems theories may eventually give rise to unification in a broad and general sense. Such a unification would be interdisciplinary and problem centered rather than discipline centered.
Biological Evolution↗
[Addiction--a contribution from the viewpoint of adolescent psychiatry].
While a single patient's addiction arises from a pattern of individual factors there appears to be a general cultural climate fostering its genesis in many variants. In the present contribution the metamorphosis of the metaparadigm from the dialectic to the dialogue is characterized as cultural transition-time demanding from the individual to cope and live with permanent contradictions and conflicts. On the background of this anthropologic situation addiction is understood as internalized foreign determination sustaining a common though antiquated scheme of psychic and social conflict conditioned by outdated patterns of education and socialisation. Addiction is appreciated as an inadequate attempt of the individual and of society toward adaptation, based on historic evolution of culture.
Adolescent↗
Child malnutrition and deprivation--observations in Guatemala and Costa Rica.
Traditional populations consisting of small tribal groups living in close contact with nature may be virtually free from endemic malnutrition owing to the relative absence of infectious diseases. Transition toward modern ways of life and population growth, leading to crowding and underdevelopment, favours endemic malnutrition due to the interaction of malnutrition and infection. Although important features of the traditional culture--breast-feeding, protective child rearing--may remain intact, they are not enough, and such populations exhibit high rates of infectious disease, malnutrition and premature death. In modern industrialized societies, malnutrition often appears related to child abuse and neglect. Organic and metabolic forms are observed but social pathology appears to be the main determinant of most malnutrition observed. Prevention and control of malnutrition requires improvement of the environment and interventions applied in a holistic manner. Emphasis should be given to education and maternal technology, and to promotion of mother-infant interactions, breast-feeding, adequate weaning procedures and detection of factors that may lead to child deprivation and abuse. Improvement is feasible for most developing nations if social forces become conscious of the needed changes, but positive elements of traditinal culture should be preserved.
Breast Feeding↗
Culture of Spirulina platensis in human urine for biomass production and O(2) evolution.
Attempts were made to culture Spirulina platensis in human urine directly to achieve biomass production and O(2) evolution, for potential application to nutrient regeneration and air revitalization in life support system. The culture results showed that Spirulina platensis grows successfully in diluted human urine, and yields maximal biomass at urine dilution ratios of 140 approximately 240. Accumulation of lipid and decreasing of protein occurred due to N deficiency. O(2) release rate of Spirulina platensis in diluted human urine was higher than that in Zarrouk medium.
Biomass↗
Evolution of CXCR4-using human immunodeficiency virus type 1 SF162 is associated with two unique envelope mutations.
CCR5-using human immunodeficiency virus type 1 (HIV-1) isolates typically gain CXCR4 use via multiple mutations in V3 and often V1/V2 regions of envelope, and patterns of mutations are distinct for each isolate. Here, we report that multiple CXCR4-using variants of a parental CCR5-using HIV-1 isolate, SF162, obtained by either target cell selection or CCR5 inhibition have a common mutation pattern characterized by the same two V3 mutations and that these mutations preexisted in some of the SF162 stocks. These results imply that SF162 has a single pathway for acquiring CXCR4 use and that prolonged culture is sufficient to select for R5X4 variants.
Cells, Cultured↗
Back to the roots of a new exon--the molecular archaeology of a SP100 splice variant.
Retropseudogenes are intronless DNA sequences sharing a high degree of homology with the cDNA of their corresponding active genes. They are thought to have originated by reverse transcription of messenger RNA and reintegration of the cDNA into the genome. Usually considered a type of evolutionary waste, they melt into the background of their surrounding DNA by the loss of similarity to the active gene or disappear from the genome by the accumulation of deletions. On the other hand, in this paper we describe the evolutionary recycling of this genomic waste. Recently, a splice variant of the gene encoding the nuclear protein SP100 was identified in which the 3' part of the cDNA is replaced by an alternative exon apparently encoding an HMG1-DNA-binding domain. We were able to show that this HMG box is contributed by a new exon arising from an HMG1 retropseudogene that we have molecularly characterized in detail. In addition to being found in human cells, corresponding fusion transcripts were shown in Pan troglodytes, Gorilla gorilla, and Hylobates lar, but not in Macaca mulatta. Genomic DNA from M. mulatta enabled us to amplify by PCR the 5' part but not the 3' part of the HMG1 retropseudogene. From our data we thus can date the underlying retrotransposition to more than 35 million years ago. Our findings offer a model as to how new exons may evolve during evolution. To our knowledge this is the first example of a retropseudogene becoming part of an active gene in which both parental parts are well characterized and remain in-frame with their cDNA.
Alternative Splicing↗
[Evolution of language: attempt at synthesis].
There are at least three traits that distinguish modern Homo sapiens from his closest relatives: bipedal locomotion, the unusual size of his brain and the ability to use symbolic language. To this day the emergence and evolution of these traits have not been explained sufficiently. New research in anthropology, linguistics, cognitive science and other disciplines shows, that the evolution of the human language faculty is a complex field that was influenced by a wide variety of factors. This paper tries to show the width of these factors and to work out the demands that are to be met by a theory of language evolution. After the introduction, in Section 2 the evolutionary principles and their role in the evolution of symbolic communication will be reviewed. Section 3 gives an overview of the results and controversies of brain evolution research, while Section 4 introduces our current knowledge of the neuronal basis of language. In Section 5 the controversies that had the greatest impact on the field and development of ways to solve them are reviewed before Section 6 summarizes the most important preadaptations for the evolving language faculty.
Animals↗
Skeletal evidence for the emergence of infectious disease in bronze and iron age northern Vietnam.
Human skeletal evidence for the emergence of chronic infectious disease in northern Vietnam is examined. The sample includes the remains of 192 individuals representing the Mid-Holocene and Bronze to Iron Ages. The objective is to see if the transition from sedentary, foraging, coastally oriented economies to centralized chiefdoms with attendant development and intensification of agriculture, trade, metal technologies, warfare, and population increase was accompanied by an emergence of and/or increase in infectious disease. It was found that skeletal evidence for infectious disease was absent in the Mid-Holocene, while over 10% of the Metal period sample exhibited lesions consistent with either infectious disease or immune system disorders. Factors potentially contributing to the emergence of infectious disease in northern Vietnam in the Metal period include: increased contact with bacterial or fungal pathogens either directly or by way of vertebrate and/or arthropod vectors; higher levels of debilitation and/or decreased levels of immunocompetence in the Metal period; and evolution of pathogens present in Mid-Holocene human hosts into more virulent forms in the Metal period. The first two factors may be related to historically and archaeologically documented major demographic (Han colonizing efforts) and economic (agricultural intensification) changes in the region during the Metal period.
Adolescent↗
Divergent evolution of hepatitis C virus in liver and peripheral blood mononuclear cells of infected patients.
In infected individuals, hepatitis C virus (HCV) exists as a variably complex population of related genetic variants known as quasispecies. The quasispecies of HCV were studied previously in 10 chronically infected patients by single-strand conformation polymorphism analysis of a segment of the envelope gene E2/NS1 containing the hypervariable region 1 and it was found that certain variants (LC variants) were present both in the liver and in peripheral blood mononuclear cells (PBMC), others (L variants) were present in the liver but not in the PBMC, and still others (C variants) showed the opposite distribution. The sequence data obtained from nine such patients are reported, indicating that, within individual subjects, L and C variants are distinct phylogenetically. Results are described on the growth of HCV in stimulated healthy donor PBMC cultures supporting the concept that genetic divergence might stem, at least in part, from virus adaptation to growth in different cell types. This information may help to understand how HCV persists and produces disease in infected patients, especially with regard to extrahepatic pathology.
Cells, Cultured↗
The evolution of a social construction: the case of male homosexuality.
Male homosexuality has been viewed by evolutionary psychologists as a Darwinian paradox, and by other social scientists as a social construction. We argue that it is better understood as an evolutionary social construction. Male homosexuality as we now know it is an 18th-century invention, but nonexclusive same-sex sexual behavior has a long evolutionary history. According to the alliance-formation hypothesis, same-sex sexuality evolved by natural selection because it created or strengthened male-male alliances and allowed low-status males to reposition themselves in the group hierarchy and thereby increase their reproductive success. This hypothesis makes sense of some odd findings about male homosexuality and helps to explain the rise in exclusive male homosexuality in the 18th century. The sociohistorical conditions around 1700 may have resulted in an increase in same-sex sexual behavior. Cultural responses to same-sex sexuality led to the spread of exclusive homosexual behavior and to the creation of a homosexual identity. Understanding male homosexuality as an evolutionary social construction can help us move beyond the traditionally polarized debate between evolutionary psychologists and social constructionists.
Attitude↗
A gene-culture model of human handedness.
A model of handedness incorporating both genetic and cultural processes is proposed, based on an evolutionary analysis, and maximum-likelihood estimates of its parameters are generated. This model has the characteristics that (i) no genetic variation underlies variation in handedness, and (ii) variation in handedness among humans is the result of a combination of cultural and developmental factors, but (iii) a genetic influence remains since handedness is a facultative trait. The model fits the data from 17 studies of handedness in families and 14 studies of handedness in monozygotic and dizygotic twins. This model has the additional advantages that it can explain why monozygotic and dizygotic twins and siblings have similar concordance rates, and no hypothetical selection regimes are required to explain the persistence of left handedness.
Biological Evolution↗