Choosy copiers

Posted on March 26, 2010

Social learning, where animals learn by observing others, can significantly reduce the costs of foraging by providing indirect information on the location and quality of food patches.  However, because  demonstrator individuals vary in their ability to indicate the most profitable sources of food, observer animals will benefit most if they can identify the most reliable demonstrators.  Using the nine-spined stickleback (Pungitius pungitius) as a study species,U.K. researchers tested the prediction that individuals should prefer to copy demonstrators that are relatively large, and therefore more successful or experienced.   Fish were first trained to distinguish between rich and poor food patches (i.e., patches where either six or two bloodworm prey were provided in a ten minute trial) that were marked by differently coloured columns.  Then the same individuals watched groups of large or small demonstrator fish feeding at the two locations after the patch profitabilities were reversed.  When the observer fish were retested, they spent significantly more time near the newly-rich patch after a demonstration by large fish than after a demonstration by small fish.  The findings show that foraging fish are more prepared to abandon their reliance on their own  personally-acquired  information when social information is available from large conspecifics.

Reference:   Duffy, G.A., Pike, T.W. & Laland, K.N.  2009.  Size-dependent directed social learning in nine-spined sticklebacks.  Animal Behaviour 78 , 371–375.

Posted in: behaviour, fish