The prevalent myth that goldfish only have a three-second memory does goldfish a great disservice, says Ellen Husain.
In fact, goldfish can retain memories for at least three months, can be trained, and can also tell the time. In experiments at Plymouth University, the diminutive members of the carp family learned to push a lever in order to get food. When the experiment was adjusted so ti lever worked for only one hou each day, the fish learned to nudge it at the right time.
Most people are surprised in evolutionary terms that goldfish would remember where, when and how to get food - a process called time-place learning. Studies at St Andrews University also suggest that minnows are as intelligent as rats. Social fish often inspect threats from predators together; if one hangs back, leaving another in danger, that individual will no longer be trusted in future. Ellen Husain
