Baby Ducks Are Capable of Abstract Thoughts

Experiments show that ducklings can find deeper meaning in the objects they imprint on.

Are ducklings the new avian Picassos? Recent research suggests they might have an abstract perspective when it comes to shape and color.

Right out of the egg, one of the first things a duckling does is recognize its mother—or at least, what it thinks is its mother. Ducklings form a bond with whatever they see in front of them, even if it’s another species, an object, or a human. Such mix-ups might suggest a chink in the evolutionary advantage of “imprinting.” But a new study, published this week in Science, suggests that the process is much more complex than biologists previously thought. Recent experiments conducted by scientists at the University of Oxford show that during imprinting, Mallard ducklings not only record sensory information, like color, sound, or smell, but also abstract information, like whether two objects are the same or different from each other.

“Even very young animals may be able to display behavioral signs of abstract thinking,” wrote University of Iowa psychologist Edward Wasserman in an accompanying editorial. In the wild, this level of cognizance probably strengthens the imprint, helping the young birds better attach to their parents.

Imprinting is a crucial stage of development in many young mammals and birds. Among avians, the process is particularly important for species that are precocial, a.k.a mobile and self-feeding soon after hatching, says Sunny Bettley, wildlife rehabilitation and outreach specialist at Sharon Audubon. Through observation, ducklings must learn to forage and swim in order to survive, Bettley explains. They need to know whom to follow, both in terms of imitating behavior and, more literally, to avoid getting lost. For this reason, wildlife rescuers must be careful about how they approach newborn ducks, she says. “Imprinted wildlife can’t be released into the wild as they won’t know how to properly or effectively find food, be aware of natural predators, or communicate with others of their species. They will not being able to reproduce.”

In the study, Oxford behavioral ecologist Alex Kacelnik and graduate student Antone Martinho III tested whether ducklings could tell if items were the same or different, and ultimately, whether they could process abstract information. In other words, could they go beyond the concrete identities of the objects and draw comparisons? In their first experiment, domestic Mallards were either introduced to objects that were the same shape (say, two spheres) or different shapes (like a cone and a rod). Next, the researchers put the ducklings in another chamber with two pairs of previously unseen objects—one pair with the same shape, one pair with different shapes. They then monitored the birds to see which objects were approached, followed, or avoided over the course of 10 minutes. As expected, the ducklings seemed to prefer pairs that were similar to the first set they imprinted on. Chicks that got identical-shaped objects tended to stick to that pattern, while those that imprinted on mismatched objects leaned toward those sets throughout the test. A second experiment that used same- or different-colored spheres yielded similar results.

“The essence of the study is that the animals couldn’t [choose] by similarity to what they had seen before,” says Kacelnik. Instead, the birds seemed to make their decisions based on the abstract relationship (defined here as same or different) between the articles they imprinted on.

Several animals, including pigeons, parrots, primates, and, of course, humans, are known to distinguish between same and different. For example, an African Gray Parrot called Alex, trained by biologist Irene Pepperberg, could shout out the one shared attribute among varying objects. But in many of these cases, the subjects were trained through a reward-based system. The ducklings, by contrast, made these distinctions without expecting a prize.

Pepperberg lauds the study for demonstrating “identity versus non-identity and the capacity for processing that level of abstraction” in baby ducks. But she also believes that the researchers have yet to confirm a true understanding of same-different in the species. If a duckling really can master this concept, it should be able to transfer that knowledge across two modalities, like shape and color, she says.

Kacelnik would like to perform tests with multiple stimuli, but adds that they’re tricky to design. Regardless, he thinks these relationships may show how a duckling processes its parents—perhaps by using a library of properties that it connects to an individual. “The mother is characterized by a particular value in all these different traits,” he says. Now, wouldn’t that make a great Hallmark card?