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Abstract Guided by concepts from life history (LH) theory, a large human research literature has tested the hypothesis that exposures to extrinsic mortality (EM) promote the development of faster LH strategies (e.g., earlier/faster reproduction, higher offspring number). A competing model proposes that, because EM in the past was intimately linked to energetic constraints, such exposures specifically led to the development of slower LH strategies. We empirically address this debate by examining (1) LH variation among small-scale societies under different environmental conditions; (2) country-, regional- and community-level correlations between ecological conditions, mortality, maturational timing, and fertility; (3) individual-level correlations between this same set of factors; and (4) natural experiments leveraging the impact of externally-caused changes in mortality on LH traits. Partially supporting each model, we found that harsh conditions encompassing energetic stress and ambient cues to EM (external cues received through sensory systems) havecountervailing effectson the development of LH strategies, both delaying pubertal maturation and promoting an accelerated pace of reproduction and higher offspring number. We conclude that, although energetics are fundamental to many developmental processes, providing afirst tierof environmental influence, this first tier alone cannot explain these countervailing effects. An importantsecond tierof environmental influence is afforded by ambient cues to EM. We advance a 2-tiered model that delineates this second tier and its central role in regulating development of LH strategies. Consideration of the first and second tier together is necessary to account for the observed countervailing shifts toward both slower and faster LH traits.
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Modeling island effects with probabilistic tier-based strictly local grammars over trees
We fuse two recent strands of work in subregular linguistics—probabilistic tier projections (Mayer, 2021) and tier-based perspectives on movement (Graf, 2022a)—into a probabilistic model of syntax that makes it easy to add gradience to traditional, categorical analyses from the syntactic literature. As a case study, we test this model on experimental data from Sprouse et al. (2016) for a number of island effects in English. We show that the model correctly replicates the superadditive effects and gradience that have been observed in the psycholinguistic literature.
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- Award ID(s):
- 1845344
- PAR ID:
- 10496688
- Publisher / Repository:
- University of Massachusetts Amherst
- Date Published:
- Journal Name:
- Proceedings of the Society for Computation in Linguistics
- ISSN:
- 2834-1007
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.7275/nz4q-6b09
