Pigeons can Place Objects in Categories, Study Finds

Pigeons can categorize objects by looking at specific characteristics, according to a new study.

Researchers at University of Iowa and colleagues found that pigeons, like humans, use selective attention to look at specific features of an object. The ability to locate unique signs helps the birds accomplish the task of sorting objects just like humans.

"The basic concept at play is selective attention. That is, in a complex world, with its booming, buzzing confusion, we don't attend to all properties of our environment. We attend to those that are novel or relevant," said Edward Wasserman, UI psychology professor and secondary author on the paper.

All animals need to be able to distinguish between a food and a potential poison or a predator and a harmless animal, according to Wasserman.

The team found that unlike other animals, pigeons learn and categorize objects simultaneously. Other animals follow a two-step thought process to sort things; step one is to learn about the object and step two is to place the object along with other objects with similar characteristics.

In the study, pigeons were shown two sets of four computer generated images on a touchscreen. The images were of bubbles, stars or spirals. The pigeons were then made to distinguish the objects.

Study results showed that pigeons could differentiate between images. According to the researchers, this selective attention could also be present in other animals such as goldfish and lizards.

"Because a pigeon's beak is midway between its eyes, we have a pretty good idea that where it is looking is where it is pecking," Wasserman said in a news release. "This could be true of any bird or fish or reptile."

Previous research by Wasserman had shown that even baboons can perform tasks that require an ability to understand the idea of relations.

Pigeons can also perform a complex string task, an intelligence test that involves a string attached to a treat.

The study is published in the Journal of Experimental Psychology: Animal Learning and Cognition.