Social-like responses are inducible in asocial Mexican cavefish despite the exhibition of strong repetitive behaviour
Abstract
Social behaviour is a hallmark of complex animal systems; however, some species appear to have secondarily lost this social ability. In these non-social species, whether social abilities are permanently lost or suppressed is unclear. The blind cavefish Astyanax mexicanus is known to be asocial. Here, we reveal that cavefish exhibited social-like interactions in familiar environments but suppressed these interactions in stress-associated unfamiliar environments. Furthermore, the level of suppression in sociality was positively correlated with that of stereotypic repetitive behaviour, as seen in mammals. Treatment with a human antipsychotic drug targeting the dopaminergic system induced social-like interactions in cavefish, even in unfamiliar environments, while reducing repetitive behaviour. Overall, these results suggest that the antagonistic association between repetitive and social-like behaviours is deeply shared from teleosts through mammals.
Data availability
All data generated and analyzed during this study are included in the supplementary Source Data file. Program scripts/codes are available in the public data depository (https://zenodo.org/record/5122894#.YPnDBR1ujsF). All raw video data are available upon request. Sample video files are available at https://zenodo.org/record/5122894#.YPnDBR1ujsF)
Article and author information
Author details
Funding
National Institutes of Health (P20GM125508)
- Masato Yoshizawa
Hawaii Community Foundation (18CON-90818)
- Masato Yoshizawa
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols (#17-2560) of the University of Hawaii at Manoa. The protocol was approved by the Committee on the Ethics of Animal Experiments of the University of Hawaii at Manoa (Permit Number: A3423-01). All vital-dye imaging were performed under ice-cold MS222 anesthesia, and every effort was made to minimize suffering
Copyright
© 2021, Iwashita & Yoshizawa
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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