ABSTRACT
Visual motion, a critical cue in communication, can be manipulated and studied using video playback methods. A primary concern for the video playback researcher is the degree to which objects presented on video appear natural to the non-human subject. Here we argue that the quality of motion cues on video, as determined by the video's image presentation rate (IPR), are of particular importance in determining a subject's social response behaviour. We present an experiment testing the effect of variations in IPR on pigeon (Columbia livia) response behaviour towards video images of courting opposite sex partners. Male and female pigeons were presented with three video playback stimuli, each containing a different social partner. Each stimulus was then modified to appear at one of three IPRs: 15, 30 or 60 progressive (p) frames per second. The results showed that courtship behaviour became significantly longer in duration as IPR increased. This finding implies that the IPR significantly affects the perceived quality of motion cues impacting social behaviour. In males we found that the duration of courtship also depended on the social partner viewed and that this effect interacted with the effects of IPR on behaviour. Specifically, the effect of social partner reached statistical significance only when the stimuli were displayed at 60 p, demonstrating the potential for erroneous results when insufficient IPRs are used. In addition to demonstrating the importance of IPR in video playback experiments, these findings help to highlight and describe the role of visual motion processing in communication behaviour.
Footnotes
Competing interests
The authors have no competing or financial interests to declare.
Author contributions
This research was conceived and designed by E.L.R.W. and N.F.T. E.L.R.W. executed the experiments, analysis and interpretation of results. N.F.T. conceived of, while D.R.S. and E.L.R.W. designed and carried out the automatic coding techniques used for analysis. E.L.R.W. drafted the manuscript, including contributions from N.F.T and D.R.S. All authors edited, revised and approved the manuscript.
Funding
This work was funded by a Natural Sciences and Engineering Research Council of Canada Discovery Grant held by N.F.T. and by contributions from the Canadian Institute for Advanced Research.
- Received December 17, 2014.
- Accepted March 27, 2015.
- © 2015. Published by The Company of Biologists Ltd
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution and reproduction in any medium provided that the original work is properly attributed.