The fast and the fractalous: Speed and tortuosity trade off in running ants

Michael Angilletta, T. C. Roth, R. S. Wilson, A. C. Niehaus, P. L. Ribeiro

Research output: Contribution to journalArticle

23 Citations (Scopus)

Abstract

1. The thermal sensitivity of locomotor performance has often been described in terms of speed, but the trajectory of locomotion may play an equally important role in capturing prey or escaping predators. Hypotheses based on physical constraints or behavioural plasticity predict relationships between the speed and the tortuosity of running, which should affect the thermal sensitivity of locomotion. 2. We measured the speed and tortuosity of running by leaf-cutter ants over a range of temperatures from 10 °C to 40 °C. Tortuosity was estimated by the fractal dimension of each path. 3. As we expected, ants ran faster at higher temperatures, but they also followed straighter (less tortuous) paths. A negative relationship between speed and tortuosity was observed both within and among thermal environments. 4. Both biomechanical and behavioural mechanisms might have caused the observed relationship. Turning at high speeds should be more difficult because of the force needed to overcome inertia, and turning at low speeds could help ants evade a predator. Staged encounters with predators should help to define the ecological significance of the trade-off between speed and tortuosity.

Original languageEnglish (US)
Pages (from-to)78-83
Number of pages6
JournalFunctional Ecology
Volume22
Issue number1
DOIs
StatePublished - Feb 2008
Externally publishedYes

Fingerprint

tortuosity
trade-off
ant
Formicidae
predators
heat
locomotion
cutters
fractal dimensions
predator
trajectories
temperature
speed
leaves
inertia
plasticity
trajectory

Keywords

  • Fractal dimension
  • Locomotor performance
  • Protean movement
  • Speed
  • Temperature

ASJC Scopus subject areas

  • Ecology

Cite this

The fast and the fractalous : Speed and tortuosity trade off in running ants. / Angilletta, Michael; Roth, T. C.; Wilson, R. S.; Niehaus, A. C.; Ribeiro, P. L.

In: Functional Ecology, Vol. 22, No. 1, 02.2008, p. 78-83.

Research output: Contribution to journalArticle

Angilletta, Michael ; Roth, T. C. ; Wilson, R. S. ; Niehaus, A. C. ; Ribeiro, P. L. / The fast and the fractalous : Speed and tortuosity trade off in running ants. In: Functional Ecology. 2008 ; Vol. 22, No. 1. pp. 78-83.
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