Did you know that the convict cichlid (Amatitlania siquia), a monogamous fish species that forms long-lasting pairs, can exhibit pessimism? In a recent study, female fish selected male partners and were then paired with preferred or non-preferred partners. The fish that were paired with non-preferred partners did not spawn as quickly as the others. Furthermore, scientists tested both groups of female fish and found that the females assigned a non-preferred mate showed pessimistic bias, suggesting that they may be in a negative affective state. The lead author likened pessimistic bias to seeing the world from a “glass half empty” point of view.
Sources: Laubu, C., Louâpre, P., & Dechaume-Moncharmont, F. X. (2019). Pair-bonding influences affective state in a monogamous fish species. Proceedings of the Royal Society B: Biological Sciences. 286. http://doi.org/10.1098/rspb.2019.0760
Sigal, S. (2019, July 20). Breakups really suck, even if you’re a fish. Retrieved from https://www.vox.com/future-perfect/2019/7/20/20700775/fish-pain-love-emotion-animal-cognition-study