UK - Scientists from the University of Oxford have shown that newly hatched ducklings can readily acquire the concepts of 'same' and 'different' - an ability previously known only in highly intelligent animals such as apes, crows and parrots.
Ducklings and other young animals normally learn to identify and follow their mother through a type of learning called imprinting, which can occur in as little as 15 minutes after hatching. Imprinting is a powerful form of learning that can allow ducklings to follow any moving object, provided they see it within the species' typical 'sensitive period' for imprinting.
In this new study, published in the journal Science, ducklings were initially presented with a pair of objects either the same as or different from each other - in shape or in colour - which moved in a circular path.
The ducklings therefore 'imprinted' on these pairs of moving objects before being tested for their preferences between different sets of objects.
About three-quarters of the ducklings preferred to follow the stimulus pair exhibiting the relationship they had learned in imprinting, and their accuracy was as good whether they had to learn the concept of equal or different, or whether they were tested with shapes or colours.
Professor Alex Kacelnik of Oxford University's Department of Zoology, who has worked extensively on learning and decision-making in animals, said: "To our knowledge this is the first demonstration of a non-human organism learning to discriminate between abstract relational concepts without any reinforcement training."
Antone Martinho, a doctoral student in Oxford's Department of Zoology and the study's first author, said: 'While it seems surprising at first that these one-day-old ducklings can learn something that normally only very intelligent species can do, it also makes biological sense. When a duckling is young, it needs to be able to stay near its mother for protection, and an error in identifying her could be fatal."