Ducklings: not the bird brains you thought they were
A new study shows baby ducks can recognise concepts of 'same' and 'different' – a feat previously thought only possible in more intelligent animals. Belinda Smith reports.
There's no doubt ducklings are incredibly cute. But inside their adorable fuzzy head is a brain capable of recognising if a pair of objects are the same or different colour or shape without any training, a new study shows.
This level of cognition was thought to be limited to more intelligent animals such as apes, parrots and crows.
The study, by Antone Martinho and Alex Kacelnik from the University of Oxford in the UK, was published in Science.
Seeing a band of fluffy ducklings follow their mother around, seemingly stuck like glue, is a common sight in springtime. This is because ducklings "imprint" on the first moving object they see after hatching – sometimes within the first 15 minutes.
To see how well ducklings can differentiate between imprinted objects and others, Martinho and Kacelnik put their adorable subjects in an arena and presented them with two objects suspended from an arm that moved them in a circle.
Pairs of objects were either the same as or different from each other in shape or in colour.
The ducklings were then tested in the arena again for their preferences between two new, different pairs of objects. For instance, if a duckling imprinted on a pair of green spheres, it may have to choose between two blue spheres (same) or a pair consisting of a pink sphere and a purple sphere (different).
If they learnt the relationship between the original pair – they were the same colour – they'd head towards the blue pair in the test.
Other ducklings, for instance, were imprinted on a cone and pyramid, then tested to see if they preferred a pair made of two spheres or a pair comprising a cuboid and cube.
And they didn't disappoint. In three-quarters of the tests, the ducklings waddled towards the pair most like their imprinted pair. And their accuracy didn't change if the test was colour- or shape-based, or if tested their ability to recognise "same" or "different".
So what's happening in their little brains?
Martinho suspects ducklings need to recognise their parent from any and all angles, so need to understand relational concepts.
'Ducks walk, swim and fly, and are constantly changing their exact shape and appearance as they extend their wings or become partially submerged, or even change angle with respect to the viewer," he says.
"If the ducklings just had a visual 'snapshot' of their mother, they would lose her.
"They need to be able to flexibly and reliably identify her, and a library of concepts and characteristics describing her is a much more efficient way to do so, compared with a visual memory of every possible configuration of the mother and her environment."
Watch some experiments in the video below.