Goldfish aren’t curious – but this makes curiosity special
Curiosity is a fundamental feature of human intelligence, and influences much about our lives. But do other animals also share this trait?
A top-down view of how the goldfish tank was set up for the study
Some mammals and birds have been shown to prefer advance information – even if it’s costly to acquire – suggesting they are curious. In contrast, new research has revealed that goldfish don’t have this preference. Goldfish share basic reinforcement learning mechanisms with birds and mammals; not preferring advance information suggests that informative preferences seen in mammals and birds aren’t just a consequence of basic learning mechanisms, but have instead evolved as a distinct trait, perhaps more than once.
The researchers, based across Biology and Experimental Psychology, gave goldfish a choice between two options, both providing a 50% reward chance after a 5 second delay. One ‘informative’ option gave a hint of the outcome immediately after choosing, while choosing the ‘non-informative’ option only resolved the uncertainty at the end of the 5 seconds. In contrast with birds and mammals, the goldfish had no preference for one over the other, even though they could tell the difference.
Co-lead researcher Dr Tiago Monteiro (Oxford Biology at the time of the study, now University of Veterinary Medicine Vienna and University of Aveiro) highlights:
“When they had information that food was coming, they stayed closer to where the food was due to be delivered, meaning that they could use information when they had it, yet overall showed no preference between the two options.”
Co-lead researcher Dr Victor Ajuwon (Oxford Biology at the time of the study, now University of Cambridge) says:
“Being motivated to learn about things that may not be immediately useful is extremely important for being better prepared for unexpected challenges. Curiosity allows us to learn diverse strands of information and how things relate to each other in the world. This can be essential for future problem solving like locating food, maintaining social bonds, or finding your way home.”
While the study only looked at goldfish, other species might respond differently to the task. Understanding which species show curiosity can give us an idea into how and why it evolved. Victor added:
“To draw more concrete conclusions about the origins of information-seeking, we need to investigate a wider range of animals. Exploring the phenomenon in invertebrates will be another way of helping to reveal how universal curiosity is in animals.”
Understanding information-seeking could also contribute to the development of artificial intelligence that can act more autonomously. Additionally, it could offer insights into mental health disorders that are characterised by too much or too little information-seeking. Senior author Alex Kacelnik (Oxford Biology), adds:
“Seeking information per se, independently of immediate benefits, is a fundamental principle of natural and artificial intelligence, hence knowing how information-seeking works and how it differs between adaptive agents can have great significance. Goldfish are intelligent enough to solve the problems they normally face, but they may not solve them in the same way as humans or other species.”
https://www.youtube.com/embed/61kSgnKGNmg?si=S5Y2fwmn_OGawupT
To read more about this research, published in Proceedings of the Royal Society B, visit: https://doi.org/10.1098/rspb.2024.2842
