Are Caribbean reef sharks, Carcharhinus perezi, able to perceive human body orientation?
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The present study examines the potential capability of Caribbean reef sharks to perceive human body orientation, as well as discussing the sharks’ swimming patterns in a person’s vicinity. A standardized video method was used to record the scenario of single SCUBA divers kneeling in the sand and the approach patterns of sharks, combined with a control group of two divers kneeling back-to-back. When approaching a single test-subject, significantly more sharks preferred to swim outside the person’s field of vision. The results suggest that these sharks are able to identify human body orientation, but the mechanisms used and factors affecting nearest distance of approach remain unclear.
KeywordsApproach Humans Swim patterns Sharks
We thank M. Tomasello and A. Miklósi for their suggestions, as well as the two anonymous reviewers for critical reading of the manuscript and editorial suggestions. Furthermore, we also thank the test-subjects for their efforts, which made this project possible.
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