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321.
Victoria Stead 《The journal of the Royal Anthropological Institute》2021,27(2):303-320
The temporary labour migrations of Pacific Islanders to work in the orchards and packing sheds of the Australian horticultural industry feed the demands for flexible labour that are marks of the precarious present. At the same time, their labour experiences call attention to the diverse, historically situated, and racialized configurations of power and risk that converge in the present moment within particular places and within the intersecting lives and bodies of differently positioned others. Focused on a fruit packing shed in north-central Victoria, and on the ni-Vanuatu workers, farmers, managers, and mediating agents who meet there, this article seeks to develop an ethnography of precarity's intersections. Here, the insecurities and fraying reciprocities widely theorized in the context of post-Fordist, neoliberal precarity articulate with the hierarchies and imaginaries of development regimes, the colonial co-production of Global North and South, and the always-precarious rhythms of horticultural production. Precarity, I argue, is neither particular to the post-Fordist relations of Western Europe, nor an all-consuming leveller of historical, cultural, and place-based difference. Rather, it emerges out of the situated convergences of diverse people and histories, and practices of both mobility and containment, producing intersecting but ultimately unequal distributions of risk. 相似文献
322.
Frances V. Adams T. Jean M. ArseneauRobar Tyler R. Bonnell Samantha M. Stead Julie A. Teichroeb 《Ecology and evolution》2021,11(7):3251
- Multi‐level societies are complex, nested social systems where basic social groups (i.e., core units) associate in a hierarchical manner, allowing animals to adjust their group sizes in response to variables such as food availability, predation, or conspecific threat. These pressures fluctuate over time and examining the extent to which this variation affects the clustering of core units into different tiers may be instrumental in understanding the evolution of multi‐level societies.
- The goal of our study was to determine the degree of temporal variability in interunit associations in a multi‐level society of Rwenzori Angolan colobus monkey (Colobus angolensis ruwenzorii), and to determine the social and ecological factors that underlie association patterns. The C. a. ruwenzorii multi‐level society consists of at least three tiers, with core units clustering into clans that share a home range in a band tier.
- We performed social network analyses on 21 months of association data from 13 core units (totaling 139 identifiable individuals) at Lake Nabugabo, Uganda. We described the patterns of variation in core‐unit associations over time and investigated how changes in rainfall, food availability, and interunit dispersals were correlated with these associations over the short‐term (month to month) and long‐term (year to year).
- Although clans were relatively stable, larger‐scale changes in association patterns included the formation of an all‐male unit and the transfer of one core unit between clans (within the band tier). Seasonally, core units associated significantly more when fruit, their preferred food source, was abundant (i.e., social networks were denser and more clustered) and there was no direct effect of rainfall seasonality or young leaf availability. Male dispersals also occurred more during periods of high fruit availability, suggesting that greater band cohesion allowed males to prospect and transfer between core units. Once males transferred, their previous and new units associated significantly more with one another than with other core units for 1–2 months postdispersal. The dispersal of five males from one core unit to another in a different clan co‐occurred with this core unit switching its clan affiliation.
- By examining temporal shifts in social network structure among core units, this study shows the interconnected roles that food availability and dispersal have in shaping the C. a. ruwenzorii multi‐level social system. Our findings highlight how ecological conditions can drive association patterns, impact interunit relationships, and influence social organization.
323.
The flowers of Digitalis purpurea respond to pollination by rapid corolla abscission without any loss of corolla turgor, nor any significant loss of corolla constituents, relative to the corollas of unpollinated flowers of a similar age. The corollas of unpollinated flowers too eventually abscise, 6 d after the stigma opens, however, they do so with only a minimal loss of fresh weight or corolla constituents. Pollination causes an increase in ethylene production detectable within 1 h. Increased ethylene production occurs initially only from the upper portion of the style, later from the lower portion, and lastly, between 23 and 48 h after pollination, from the ovary plus calyx. The pollination response can be induced by exogenous ethylene, the degree of weakening of the corolla abscission zone being dependent upon the concentration and duration of the exposure period and on the stage of flower development. The regulation of ethylene biosynthesis and its involvement in the control of pollination-induced corolla abscission are discussed. 相似文献