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Temporal Structuring (temporal + structuring)

Distribution by Scientific Domains

Life Sciences	75%

Selected Abstracts

Past Times: Temporal Structuring of History and Memory

ETHOS, Issue 2 2006
Kevin Birth
In On Collective Memory, Maurice Halbwachs asks, "Why does society establish landmarks in time that are placed close together,and usually in a very irregular manner, since for certain periods they are almost entirely lacking,whereas around such salient events sometimes many other equally salient events seem to gather, just as street signs and other signposts multiply as a tourist attraction approaches?" (1992:175). The recognition of the "irregular manner" of history and memory only emerges in contrast to a concept of the regularity of time implied by objectifying chronologies. Furthermore, such irregularity suggests that concepts of time other than chronology are crucial for understanding representations of the past, and experiences of the past in the present. This article draws on nondirected interviews conducted in rural Trinidad in which subjects discussed significant events in their lives. In examining this material, I address Halbwachs's question by emphasizing nonchronological, cultural models of time that organize autobiographical narratives. These cultural models position autobiographical narratives in space and connect them to events of historical significance. [time, memory, intersubjectivity, labor, Trinidad] [source]

Geographic variations of seasonality and coexistence in communities: The role of diversity and climate

AUSTRAL ECOLOGY, Issue 7 2009
ANDRÉS CANAVERO
Abstract One of the most conspicuous and widely analyzed patterns in ecology is the latitudinal gradient in species richness. Over the 200 years since its recognition, several hypotheses have accumulated in order to account for spatial variations in diversity. Geographic variations in seasonality have been repeatedly proposed as a determinant of community richness. However, the geographic structure of community seasonality has not yet been analyzed. In the present work we evaluated three hypotheses that account for variations in the temporal structuring of communities: first, environmental seasonality determines community seasonality; second, community richness determines its degree of structuring; and third, the presence of an increase in species segregation with latitude, reflected in a pattern of species negative co-occurrence. The hypotheses were evaluated using path analysis on 29 amphibian communities from South America, connecting latitude, environmental conditions, diversity, seasonality, and coexistence structure , nestedness and negative co-occurrence , within communities. Latitude positively affects community seasonality through an increase in temperature seasonality, but a weak negative direct effect suggests that other variables not considered in the model , such as the strength of biotic interactions , could also be involved. Both latitude and diversity (directly and indirectly) determine an increase in negative co-occurrence and nestedness. This suggests that groups of species that are mutually nested in time are internally segregated. Further, the strength of this structure is determined by community diversity and latitude. Temporal structuring of a community is associated with latitude and diversity, pointing to the existence of a systematic change in community organization far beyond, but probably interrelated, with the recognized latitudinal trend in richness. The available information and analysis supported the three hypotheses evaluated. [source]

Seasonality of a Diverse Beetle Assemblage Inhabiting Lowland Tropical Rain Forest in Australia

BIOTROPICA, Issue 3 2009
Peter S. Grimbacher
ABSTRACT One of the least understood aspects of insect diversity in tropical rain forests is the temporal structuring, or seasonality, of communities. We collected 29,986 beetles of 1473 species over a 4-yr period (45 monthly samples), with the aim to document the temporal dynamics of a trophically diverse beetle assemblage from lowland tropical rain forest at Cape Tribulation, Australia. Malaise and flight interception traps were used to sample adult beetles at five locations at both ground and canopy levels. Beetles were caught throughout the year, but individual species were patchy in their temporal distribution, with the 124 more abundant species on average being present only 56 percent of the time. Climatic variables (precipitation, temperature, and solar radiation) were poorly correlated with adult beetle abundance, possibly because: (1) seasonality of total beetle abundance was slight; (2) the peak activity period (September,November) did not correspond to any climatic maxima or minima; or (3) responses were nonlinear owing to the existence of thresholds or developmental time-lags. Our results do not concur with the majority of tropical insect seasonality studies suggesting a wet season peak of insect activity, perhaps because there is no uniform pattern of insect seasonally for the humid tropics. Herbivores showed low seasonality and individual species' peaks were less temporally aggregated compared to nonherbivores. Canopy-caught and larger beetles (> 5 mm) showed greater seasonality and peaked later in the year compared to smaller or ground-caught beetles. Thus seasonality of adult beetles varied according to the traits of feeding ecology, body size, and habitat strata. [source]