Mass enhances speed but diminishes turn capacity in terrestrial pursuit predators

  1. Rory P Wilson  Is a corresponding author
  2. Iwan W Griffiths
  3. Michael GL Mills
  4. Chris Carbone
  5. John W Wilson
  6. David M Scantlebury
  1. Swansea University, Wales
  2. The Lewis Foundation, South Africa
  3. Zoological Society of London, United Kingdom
  4. University of Pretoria, South Africa
  5. Queen's University Belfast, United Kingdom

Abstract

The dynamics of predator-prey pursuit appears complex, making the development of a framework explaining predator and prey strategies problematic. We develop a model for terrestrial, cursorial predators to examine how animal mass modulates predator and prey trajectories and affects best strategies for both parties. We incorporated the maximum speed-mass relationship with an explanation of why larger animals should have greater turn radii; the forces needed to turn scale linearly with mass whereas the maximum forces an animal can exert scale to a 2/3 power law. This clarifies why in a meta-analysis, we found a preponderance of predator/prey mass ratios that minimized the turn radii of predators compared to their prey. It also explained why acceleration data from wild cheetahs pursuing different prey showed different cornering behaviour with prey type. The outcome of predator prey pursuits thus depends critically on mass effects and the ability of animals to time turns precisely.

Article and author information

Author details

  1. Rory P Wilson

    Swansea Lab for Animal Movement, Department of Biosciences, College of Science, Swansea University, Swansea, Wales
    For correspondence
    r.p.wilson@swansea.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
  2. Iwan W Griffiths

    College of Engineering, Swansea University, Swansea, Wales
    Competing interests
    The authors declare that no competing interests exist.
  3. Michael GL Mills

    The Lewis Foundation, Johannesburg, South Africa
    Competing interests
    The authors declare that no competing interests exist.
  4. Chris Carbone

    Institute of Zoology, Zoological Society of London, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  5. John W Wilson

    Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa
    Competing interests
    The authors declare that no competing interests exist.
  6. David M Scantlebury

    School of Biological Sciences, Institute for Global Food Security, Queen's University Belfast, Belfast, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.

Ethics

Animal experimentation: Permission and ethical clearance were granted by SANParks ethical and research committees to conduct the field research, Project Number 2006-05-10 MGMI. The study was performed in accordance with the commendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All immobilizationand collaring of wild animals was conducted by a registered individual (GM), under the direction of a SANParks veterinarian.

Reviewing Editor

  1. Iain D Couzin, Princeton University, United States

Publication history

  1. Received: January 14, 2015
  2. Accepted: August 2, 2015
  3. Accepted Manuscript published: August 7, 2015 (version 1)
  4. Version of Record published: August 21, 2015 (version 2)

Copyright

© 2015, Wilson 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. Rory P Wilson
  2. Iwan W Griffiths
  3. Michael GL Mills
  4. Chris Carbone
  5. John W Wilson
  6. David M Scantlebury
(2015)
Mass enhances speed but diminishes turn capacity in terrestrial pursuit predators
eLife 4:e06487.
https://doi.org/10.7554/eLife.06487

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