1. Ecology
  2. Neuroscience
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Burst muscle performance predicts the speed, acceleration, and turning performance of Anna's hummingbirds

  1. Paolo S Segre
  2. Roslyn Dakin
  3. Victor B Zordan
  4. Michael H Dickinson
  5. Andrew D Straw
  6. Douglas L Altshuler  Is a corresponding author
  1. University of British Columbia, Canada
  2. University of California, Riverside, United States
  3. California Institute of Technology, United States
Research Article
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Cite this article as: eLife 2015;4:e11159 doi: 10.7554/eLife.11159

Abstract

Despite recent advances in the study of animal flight, the biomechanical determinants of maneuverability are poorly understood. It is thought that maneuverability may be influenced by intrinsic body mass and wing morphology, and by physiological muscle capacity, but this hypothesis has not yet been evaluated because it requires tracking a large number of free flight maneuvers from known individuals. We used an automated tracking system to record flight sequences from 20 Anna's hummingbirds flying solo and in competition in a large chamber. We found that burst muscle capacity predicted most performance metrics. Hummingbirds with higher burst capacity flew with faster velocities, accelerations, and rotations, and they used more demanding complex turns. In contrast, body mass did not predict variation in maneuvering performance, and wing morphology predicted only the use of arcing turns and high centripetal accelerations. Collectively, our results indicate that burst muscle capacity is a key predictor of maneuverability.

Article and author information

Author details

  1. Paolo S Segre

    Department of Zoology, University of British Columbia, Vancouver, Canada
    Competing interests
    The authors declare that no competing interests exist.
  2. Roslyn Dakin

    Department of Zoology, University of British Columbia, Vancouver, Canada
    Competing interests
    The authors declare that no competing interests exist.
  3. Victor B Zordan

    Department of Computer Science and Engineering, University of California, Riverside, Riverside, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Michael H Dickinson

    Biology and Bioengineering, California Institute of Technology, Pasadena, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Andrew D Straw

    Biology and Bioengineering, California Institute of Technology, Pasadena, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Douglas L Altshuler

    Department of Zoology, University of British Columbia, Vancouver, Canada
    For correspondence
    doug@zoology.ubc.ca
    Competing interests
    The authors declare that no competing interests exist.

Ethics

Animal experimentation: All procedures were conducted under approval of the Institutional Animal Care and Use Committee at the University of California, Riverside and the Animal Care Committee at the University of British Columbia.

Reviewing Editor

  1. Russ Fernald, Stanford University, United States

Publication history

  1. Received: August 27, 2015
  2. Accepted: November 13, 2015
  3. Accepted Manuscript published: November 19, 2015 (version 1)
  4. Version of Record published: January 18, 2016 (version 2)

Copyright

© 2015, Segre 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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