Multiple preferred escape trajectories are explained by a geometric model incorporating prey's turn and predator attack endpoint
Abstract
The escape trajectory (ET) of prey - measured as the angle relative to the predator's approach path - plays a major role in avoiding predation. Previous geometric models predict a single ET; however, many species show highly variable ETs with multiple preferred directions. Although such a high ET variability may confer unpredictability to avoid predation, the reasons why animals prefer specific multiple ETs remain unclear. Here, we constructed a novel geometric model that incorporates the time required for prey to turn and the predator's position at the end of its attack. The optimal ET was determined by maximizing the time difference of arrival at the edge of the safety zone between the prey and predator. By fitting the model to the experimental data of fish Pagrus major, we show that the model can clearly explain the observed multiple preferred ETs. By changing the parameters of the same model within a realistic range, we were able to produce various patterns of ETs empirically observed in other species (e.g., insects and frogs): a single preferred ET and multiple preferred ETs at small (20-50°) and large (150-180°) angles from the predator. Our results open new avenues of investigation for understanding how animals choose their ETs from behavioral and neurosensory perspectives.
Data availability
The datasets (Dataset1-5) of the escape response in P. major, used for statistical analysis and figures, and the R code (Source code 1-3) for the mathematical model, statistical analysis, and figures are available in Figshare: https://figshare.com/s/bea4ee4e7f7664ccd80c.
Article and author information
Author details
Funding
Japan Society for the Promotion of Science (Grants-in-Aid for Young Scientists B,17K17949)
- Yuuki Kawabata
Japan Society for the Promotion of Science (Grant-in-Aid for Scientific Research on Innovative Areas,19H04936)
- Yuuki Kawabata
Sumitomo Foundation (Grant for Environmental Research Projects,153128)
- Yuuki Kawabata
ISM Cooperative Research Program (2014-ISM.CRP-2006)
- Yuuki Kawabata
- Ken-ichiro Shimatani
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: The animal care and experimental procedures were approved by the Animal Care and Use Committee of the Faculty of Fisheries (Permit No. NF-0002), Nagasaki University in accordance with the Guidelines for Animal Experimentation of the Faculty of Fisheries and the Regulations of the Animal Care and Use Committee, Nagasaki University.
Copyright
© 2023, Kawabata et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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