Head Movements during Visual Orienting Toward Moving Prey in the Lizard Takydromus tachydromoides

Miyuki Fukudome, Yoshifumi Yamawaki

Research output: Contribution to journalReview article

Abstract

It is important to investigate visual orienting in reptiles to better understand the basic organization of the oculomotor system in vertebrates. However, quantitative analyses of visual orienting behavior in reptiles have rarely been conducted, except in chameleons. In the present study, we videorecorded the head and body movements of the lizard Takydromus tachydromoides during visual tracking of moving prey and analyzed them frame-by-frame. Before approaching prey, visual tracking mainly consisted of brief intermittent turns of the head (saccade). After the head saccades, the angular position of the prey relative to the lizard head was kept at 10-70° (laterally) in most cases, rather than at 0° (in front). In addition, the ratio of the amplitude of the head saccades to prey position was 0.2-0.3, which is much smaller than 1, suggesting that the head did not orient exactly toward the prey after most saccades. These results were observed under both white (homogeneous) and grating (structured) backgrounds. Possible functions of head saccades in the lizard are discussed.

Original languageEnglish
Pages (from-to)468-474
Number of pages7
JournalZoological science
Volume34
Issue number6
DOIs
Publication statusPublished - Dec 1 2017

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lizards
reptiles
Chamaeleonidae
vertebrates

All Science Journal Classification (ASJC) codes

  • Animal Science and Zoology

Cite this

Head Movements during Visual Orienting Toward Moving Prey in the Lizard Takydromus tachydromoides. / Fukudome, Miyuki; Yamawaki, Yoshifumi.

In: Zoological science, Vol. 34, No. 6, 01.12.2017, p. 468-474.

Research output: Contribution to journalReview article

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