Monogamous fish found to show pessimistic bias when separated from mate

cichlid
Credit: CC0 Public Domain

A team of researchers at the University of Burgundy has found that a certain type of monogamous female fish exhibits a pessimistic bias when separated from its mate. In their paper published in Proceedings of the Royal Society B, the group describes experiments they conducted with convict cichlid fish and what they found.

When humans pair-bond in a sexually relationship, there is an element of emotion involved—but what about other animals? That was the question the researchers sought to answer. To learn more, they conducted experiments with convict cichlid fish in their lab.

In the wild, convict mate monogamously. After , when the female produces , the males hang around to protect her and the eggs. And after the eggs hatch, the young are protected by both parents. To learn more about the bonds they forge, the researchers conducted a two-part experiment.

In the first part of the experiment, the researchers separated a large tank into three sections. They placed a female in the middle tank and a male in each of the other two sections. The team watched to see which she demonstrated a preference for by cozying up to one or the other. The researchers then put one of the males in with the female and allowed them to mate. They report that the who were allowed to mate with their preferred choice spawned faster, had more offspring and took better care of them compared to those paired with a rejected male.

  • Monogamous fish found to show pessimistic bias when separated from mate
    The same set-up was used for experiments 1 and 2. The box in the front of the tank was only introduced in experiment 2. Credit: Proceedings of the Royal Society B: Biological Sciences (2019). DOI: 10.1098/rspb.2019.0760
  • To effectively measure each fish's mental response to separation, researchers from the University of Burgundy in Dijon trained f
    To effectively measure each fish's mental response to separation, researchers from the University of Burgundy in Dijon trained females to use their mouths to open two small boxes, placed either side of their tanks

In the second part of the experiment, the researchers trained the females to recognize the difference between a box containing food and one that was empty. Then, they introduced a new box that required investigation to determine if it held food. The level of interest interest they showed in investigating the new box was considered a marker of her mood. They found that when her chosen mate was present in the tank with her, she expressed far more interest in checking out the new box than if the rejected male was with her. The researchers claim this is an example of "pessimistic bias," demonstrating that the females do become gloomier when separated from their desired mate.


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More information: Chloé Laubu et al. Pair-bonding influences affective state in a monogamous fish species, Proceedings of the Royal Society B: Biological Sciences (2019). DOI: 10.1098/rspb.2019.0760

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Citation: Monogamous fish found to show pessimistic bias when separated from mate (2019, June 12) retrieved 21 August 2019 from https://phys.org/news/2019-06-monogamous-fish-pessimistic-bias.html
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Jun 12, 2019
I wonder just what , exactly, the information will be applicable to?
Learning about 'bonds' implies that they want to know how to overcome the individual's choice which leads a thinking individual to consider that the social media would kill for this application refined down to media manipulation. Your and my future, ladies, altho in my case, my future is extremely limited.

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