Fuzzy little creatures can learn abstract concepts like “same” and “different” within hours of hatching.
By Nathan Collins
Despite what many people believe, scientists have known for decades that abstract reasoning is not exclusively available to human beings. A new study proves that fact once again: Mallard ducklings can learn the concepts “same” and “different” and develop preferences for one or the other with a bare minimum of training and within just two hours of hatching.
Anyone who’s paid attention to our evolving understanding of learning in animals knows that human beings aren’t the only intelligent creatures. In one especially remarkable experiment, researchers taught bees to identify whether two smells were the same or different, although such lessons often require extensive training using reinforcement learning (think Pavlov’s dogs).
To see if animals could learn even faster, University of Oxford zoologists Antone Martinho and Alex Kacelnik looked to a different kind of learning, called filial imprinting. Ordinarily, that’s the process by which animals form attachments to their parents, but it’s also been used extensively by psychologists to study how humans and other animals learn in the earliest phases of their lives.
“Animals not generally believed to be especially intelligent are capable of abstract thought.”
Martinho and Kacelnik exposed 36 one- and two-day old ducklings to a single pair of objects that were the same — a pair of pyramids, say — and another 36 to a pair of different objects — a cone and a cylinder, for example. Then, they tested whether the ducklings showed a preference for one style of pairing over the other. For example, some ducklings were first exposed to a pair of pyramids, then put in a box with two new pairs of objects — four objects total — one illustrating “same” and one illustrating “different” — like a “same” pair of matched spheres alongside a “different” cube and rectangular box pairing. If more ducklings were drawn to the pair of matched spheres, that would suggest they had learned the concepts “same” and “different” and formed a preference for one — in this case, “same.”
And that’s exactly what happened: Two-thirds of the ducklings who’d been exposed to a pair of identical objects during the first phase approached pairs of identical objects in the second phase, while a third approached the mismatched pair. Likewise, two-thirds of the ducklings exposed to a pair of mismatched objects in the first phase were drawn to mismatched objects in the second phase, while only a third preferred the matched pair. The researchers confirmed those results in a second experiment with 80 ducklings, this time using same- or different-colored spheres.
In an accompanying commentary on the research, University of Iowa psychologist Edward Wasserman notes that, while humans are capable of much more than ducks, “animals not generally believed to be especially intelligent are capable of abstract thought.” What’s more, “we should appreciate that whatever heights of cognition may be attainable by humans must have arisen via an evolutionary process about which we may gain key insights by studying the cognitive processes of our animal kin.”