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Adaptive Patterns (adaptive + pattern)
Selected AbstractsDoing and Being Well (for the Most Part): Adaptive Patterns of Narrative Self-Evaluation During BereavementJOURNAL OF PERSONALITY, Issue 3 2001Jack J. Bauer Narrative self-evaluation patterns were studied in relation to longitudinal measures of adaptation to the death of a spouse in midlife. Narrative self evaluations, identified in open-ended interview transcripts at 6 months post-loss, were coded as either positive or negative and as either doing-based (evaluations of "what one does") or being-based (evaluations of "what one is"). These narrative variables were then compared with separate, clinical-interview measures of grief at 6, 14, and 25 months post-loss. Results confirmed three predictions. First, participants who made an optimal proportion of positive to negative self-evaluations (approximately a 5:1 positive-to-negative ratio) had lower grief levels over time than did those who made either higher or lower proportions. Second, the tendency to focus on evaluations of what one does rather than what one is predicted lower grief levels over time. Third, participants who directly integrated doing-based and being-based self-evaluations had lower grief levels over time than those who did not link the two. Implications for the narrative construction of personal meaning and identity in relation to adaptation are discussed. [source] THE ADAPTIVE DYNAMICS OF ALTRUISM IN SPATIALLY HETEROGENEOUS POPULATIONSEVOLUTION, Issue 1 2003JEAN-FRANÇOIS LE GALLIARD Abstract., We study the spatial adaptive dynamics of a continuous trait that measures individual investment in altruism. Our study is based on an ecological model of a spatially heterogeneous population from which we derive an appropriate measure of fitness. The analysis of this fitness measure uncovers three different selective processes controlling the evolution of altruism: the direct physiological cost, the indirect genetic benefits of cooperative interactions, and the indirect genetic costs of competition for space. In our model, habitat structure and a continuous life cycle makes the cost of competing for space with relatives negligible. Our study yields a classification of adaptive patterns of altruism according to the shape of the costs of altruism (with decelerating, linear, or accelerating dependence on the investment in altruism). The invasion of altruism occurs readily in species with accelerating costs, but large mutations are critical for altruism to evolve in selfish species with decelerating costs. Strict selfishness is maintained by natural selection only under very restricted conditions. In species with rapidly accelerating costs, adaptation leads to an evolutionarily stable rate of investment in altruism that decreases smoothly with the level of mobility. A rather different adaptive pattern emerges in species with slowly accelerating costs: high altruism evolves at low mobility, whereas a quasi-selfish state is promoted in more mobile species. The high adaptive level of altruism can be predicted solely from habitat connectedness and physiological parameters that characterize the pattern of cost. We also show that environmental changes that cause increased mobility in those highly altruistic species can beget selection-driven self-extinction, which may contribute to the rarity of social species. [source] Insularity and adaptation in coupled victim,enemy associationsJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 4 2001M. E. Hochberg Employing a mathematical model we show how insularity, genotypic interactions and victim life-history/demography can influence adaptation in a simple enemy,victim interaction where genotypes migrate between a large source and a smaller, initially unoccupied, isolated habitat. We find that when there are explicit costs to heightened enemy virulence and victim resistance, large/close islands resemble their immigration sources, whereas small and/or distant islands tend to be occupied only by the least defended victims and least virulent enemies. In a model with no explicit cost to genotypic identity, frequencies do not differ on average between source and island. Despite these trends in genotype frequencies, for a range of realistic conditions, both cost and cost-free genotypic interactions yield an increase in the frequency of resistant encounters as a function of isolation. Moreover, in models with explicit costs, maximal island to island variation in genotypic frequencies is found on islands of intermediate distance from the source. In contrast, the model without explicit costs produces more variable communities, attaining maximum variability in genotypic frequencies at the most isolated islands. We hypothesize that adaptive patterns in mainland,island comparisons may differ substantially from those generated by centre-periphery comparisons in continental systems. [source] | ||||||||||