Summary

Computer-Generated Animal Model Stimuli

Published: July 29, 2007
doi:

Summary

Computer-generated stimuli using the Jacky dragon as a model.

Abstract

Communication between animals is diverse and complex. Animals may communicate using auditory, seismic, chemosensory, electrical, or visual signals. In particular, understanding the constraints on visual signal design for communication has been of great interest. Traditional methods for investigating animal interactions have used basic observational techniques, staged encounters, or physical manipulation of morphology. Less intrusive methods have tried to simulate conspecifics using crude playback tools, such as mirrors, still images, or models. As technology has become more advanced, video playback has emerged as another tool in which to examine visual communication (Rosenthal, 2000). However, to move one step further, the application of computer-animation now allows researchers to specifically isolate critical components necessary to elicit social responses from conspecifics, and manipulate these features to control interactions. Here, I provide detail on how to create an animation using the Jacky dragon as a model, but this process may be adaptable for other species. In building the animation, I elected to use Lightwave 3D to alter object morphology, add texture, install bones, and provide comparable weight shading that prevents exaggerated movement. The animation is then matched to select motor patterns to replicate critical movement features. Finally, the sequence must rendered into an individual clip for presentation. Although there are other adaptable techniques, this particular method had been demonstrated to be effective in eliciting both conspicuous and social responses in staged interactions.

Protocol

Animation Design Object Scan Acquire taxidermic lizard. Scan the model with a Konica Minolta VI-9i. It produces a 3D object (*.lwo and *.obj files) in a single polygon mesh of 50,000 polygons. Lightwave® v8.3 has two programs used for 3D animation: Modeller and Layout. Lightwave® Modeller designs and manipulates the object. Lightwave® Layout program creates animation scenes. Lightwave® Modeller and Layout have three dimensions of positioning, orientation…

Discussion

Computer-generated animations are increasingly becoming a popular tool in which to investigate questions regarding communication in animal behaviour. By using animation techniques, researchers can focus on specific aspects of signal design, and manipulate features that previously were unable to be investigated due to limited technology. Although conventional staged animal encounters still demonstrate theoretical principles, animation techniques now provide a sophisticated tool for examining more detailed interactions.

Disclosures

The authors have nothing to disclose.

Acknowledgements

I would like to thank Daniel Van Dyk from the Centre for the Integrative Study of Animal Behavour (CISAB) for much help in model design and access to archival video. Christopher Evans (CISAB) provided technical support, Daniel Warner (University of Sydney) provided the taxidermic model, and Richard Peters (Australian National University) provided early design features.

Materials

Material Name Type Company Catalogue Number Comment
New Item Digital camera Konica Minolta Holdings, Inc. VI-9i Used to acquire 3D mesh (done by New Dawn® – Bexley North, NSW Australia)
Lightwave® 3D Software program NewTek Inc. v8.3 To create animation
Canon Digital camera Canon, Inc. EOS 5D 12.8 megapixels
Grab Software program Apple Computer, Inc. v1.2 Extract texture from photographs and UV map
Adobe® Photoshop® Elements Software program Adobe Systems Inc. v3.0 Extract texture from photographs
Render Farm Commander Software program Bruce Rayne© v2.9 Mass rendering across local area network
Mac Pro Computer Apple Computer, Inc.   Four dual processors (eight threads); Create and render animation
Sony MiniDV Digital video recorder Sony Corporation GV-D300E Playback stimuli during stimulus acquisition
Sony Trintron Colour viewfinder Sony Corporation PVM-14M2A One monitor for stimulus acquisition
Canon Digital camcorder Cannon Inc. MV650i Records behavior during stimulus acquisition

References

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  2. Newtek, Inc, Lightwave [8] Reference Manual. , (2004).
  3. Ord, T. J., Evans, C. S. Interactive video playback and opponent assessment in lizards. Behav. Process. 59, 55-65 (2002).
  4. Ord, T. J., Peters, R. A., Evans, C. S., Taylor, A. J. Digital video playback and visual communication in lizards. Anim. Behav. 63, 879-890 (2002).
  5. Rosenthal, G. G. Design considerations and techniques for constructing video stimuli. Acta Ethol. 3, 49-54 (2000).
  6. Van Dyk, D. A., Evans, C. S. Familiar-unfamiliar discrimination based on visual cues in the Jacky dragon, Amphibolurus muricatus. Anim. Behav. 74, 33-44 (2007).
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Cite This Article
Woo, K. L. Computer-Generated Animal Model Stimuli. J. Vis. Exp. (6), e243, doi:10.3791/243 (2007).

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