Drosophila uses a tripod gait across all walking speeds, and the geometry of the tripod is important for speed control

  1. Chanwoo Chun
  2. Tirthabir Biswas
  3. Vikas Bhandawat  Is a corresponding author
  1. Duke University, United States
  2. Janelia Research Campus, Howard Medical Institute, United States
  3. Drexel University, United States

Abstract

Changes in walking speed are characterized by changes in both the animal's gait and the mechanics of its interaction with the ground. Here we study these changes in walking Drosophila. We measured the fly's center of mass (CoM) movement with high spatial resolution and the position of its footprints. Flies predominantly employ a modified tripod gait that only changes marginally with speed. The mechanics of a tripod gait can be approximated with a simple model – angular and radial spring-loaded inverted pendulum (ARSLIP) – which is characterized by two springs of an effective leg that become stiffer as the speed increases. Surprisingly, the change in the stiffness of the spring is mediated by the change in tripod shape rather than a change in stiffness of the individual leg. The effect of tripod shape on mechanics can also explain the large variation in kinematics among insects, and ARSLIP can model these variations.

Data availability

Data is available on Dryad under doi:10.5061/dryad.m63xsj41g and Github https://github.com/vbhandawat/FlyTripod_eLife_2021/

The following data sets were generated

Article and author information

Author details

  1. Chanwoo Chun

    Department of Biology, Duke University, Durham, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0759-6727
  2. Tirthabir Biswas

    Janelia Research Campus, Howard Medical Institute, Ashburn, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Vikas Bhandawat

    Biomedical Engineering, Sciences and Health Systems, Drexel University, Philadelphia, United States
    For correspondence
    vb468@drexel.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2608-0403

Funding

National Science Foundation (IOS-1652647)

  • Vikas Bhandawat

National Institute on Deafness and Other Communication Disorders (RO1DC015827)

  • Vikas Bhandawat

National Institute of Neurological Disorders and Stroke (RO1NS097881)

  • Vikas Bhandawat

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

Reviewing Editor

  1. Gordon J Berman, Emory University, United States

Publication history

  1. Received: December 17, 2020
  2. Accepted: January 22, 2021
  3. Accepted Manuscript published: February 3, 2021 (version 1)
  4. Version of Record published: March 4, 2021 (version 2)

Copyright

© 2021, Chun 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. Chanwoo Chun
  2. Tirthabir Biswas
  3. Vikas Bhandawat
(2021)
Drosophila uses a tripod gait across all walking speeds, and the geometry of the tripod is important for speed control
eLife 10:e65878.
https://doi.org/10.7554/eLife.65878

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