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Statistical structure of locomotion and its modulation by odors

  1. Liangyu Tao
  2. Siddhi Ozarkar
  3. Jeffrey M Beck
  4. Vikas Bhandawat  Is a corresponding author
  1. Duke University, United States
Research Article
  • Cited 13
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Cite this article as: eLife 2019;8:e41235 doi: 10.7554/eLife.41235


Most behaviors such as making tea are not stereotypical but have an obvious structure. However, analytical methods to objectively extract structure from non-stereotyped behaviors are immature. In this study, we analyze the locomotion of fruit flies and show that this non-stereotyped behavior is well-described by a Hierarchical Hidden Markov Model (HHMM). HHMM shows that a fly's locomotion can be decomposed into a few locomotor features, and odors modulate locomotion by altering the time a fly spends performing different locomotor features. Importantly, although all flies in our dataset use the same set of locomotor features, individual flies vary considerably in how often they employ a given locomotor feature, and how this usage is modulated by odor. This variation is so large that the behavior of individual flies is best understood as being grouped into at least 3-5 distinct clusters, rather than variations around an average fly.

Data availability

Data has been deposited in Dryad Data Repository and is available at doi:10.5061/dryad.m930f2m.

The following data sets were generated

Article and author information

Author details

  1. Liangyu Tao

    Department of Biology, Duke University, Durham, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Siddhi Ozarkar

    Department of Biology, Duke University, Durham, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Jeffrey M Beck

    Department of Neurobiology, Duke University, Durham, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Vikas Bhandawat

    Department of Biology, Duke University, Durham, United States
    For correspondence
    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


National Institute of Neurological Disorders and Stroke

  • Vikas Bhandawat

National Institute on Deafness and Other Communication Disorders

  • Vikas Bhandawat

National Science Foundation

  • 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. Ronald L Calabrese, Emory University, United States

Publication history

  1. Received: August 21, 2018
  2. Accepted: January 5, 2019
  3. Accepted Manuscript published: January 8, 2019 (version 1)
  4. Version of Record published: February 4, 2019 (version 2)
  5. Version of Record updated: March 15, 2019 (version 3)


© 2019, Tao 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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