Productivity loss associated with functional disability in a contemporary small-scale subsistence population

  1. Jonathan Stieglitz  Is a corresponding author
  2. Paul L Hooper
  3. Benjamin C Trumble
  4. Hillard Kaplan
  5. Michael D Gurven
  1. Universite Toulouse 1 Capitole, France
  2. Chapman University, United States
  3. Arizona State University, United States
  4. University of California, Santa Barbara, United States

Abstract

In comparative cross-species perspective, humans experience unique physical impairments with potentially large consequences. Quantifying the burden of impairment in subsistence populations is critical for understanding selection pressures underlying strategies that minimize risk of production deficits. We examine among forager-horticulturalists whether compromised bone strength (indicated by fracture and lower bone mineral density, BMD) is associated with subsistence task cessation; we estimate the magnitude of productivity losses associated with compromised bone strength. Fracture is associated with cessation of hunting, tree chopping and walking long distances, but not tool manufacture. Age-specific productivity losses from hunting cessation associated with fracture and lower BMD are substantial: ~397 lost kcals/day, with expected future losses of up to 1.9 million kcals (22% of expected production). Productivity loss is thus substantial for high strength and endurance tasks. Determining the extent to which impairment obstructs productivity in contemporary subsistence populations improves our ability to infer past consequences of impairment.

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Data that support the findings of this study are available on Dryad.

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Article and author information

Author details

  1. Jonathan Stieglitz

    Institute for Advanced Study in Toulouse, Universite Toulouse 1 Capitole, Toulouse, France
    For correspondence
    jonathan.stieglitz@iast.fr
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5985-9643
  2. Paul L Hooper

    Economic Science Institute, Chapman University, Orange, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Benjamin C Trumble

    School of Human Evolution and Social Change, Arizona State University, Tempe, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Hillard Kaplan

    Economic Science Institute, Chapman University, Orange, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Michael D Gurven

    University of California, Santa Barbara, Santa Barbara, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5661-527X

Funding

National Institutes of Health (R01AG024119)

  • Jonathan Stieglitz
  • Benjamin C Trumble
  • Hillard Kaplan
  • Michael D Gurven

National Science Foundation (1748282)

  • Jonathan Stieglitz

Arizona State University

  • Benjamin C Trumble

University of California, Santa Barbara

  • Michael D Gurven

Agence Nationale de la Recherche (ANR-17-EURE-0010)

  • Jonathan Stieglitz

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Ethics

Human subjects: Institutional IRB approval was granted by UNM (HRRC # 07-157) and UCSB (# 3-16-0766), as was informed consent at three levels: (1) Tsimane government that oversees research projects, (2) village leadership, and (3) study participants.

Reviewing Editor

  1. George H Perry, Pennsylvania State University, United States

Publication history

  1. Received: September 10, 2020
  2. Accepted: November 30, 2020
  3. Accepted Manuscript published: December 1, 2020 (version 1)
  4. Version of Record published: December 16, 2020 (version 2)

Copyright

© 2020, Stieglitz et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Jonathan Stieglitz
  2. Paul L Hooper
  3. Benjamin C Trumble
  4. Hillard Kaplan
  5. Michael D Gurven
(2020)
Productivity loss associated with functional disability in a contemporary small-scale subsistence population
eLife 9:e62883.
https://doi.org/10.7554/eLife.62883
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