A new study revealed that pigeons are smarter than previously thought and that they learn the same way children do.

Researchers at the University of Iowa experimented on three pigeons by playing the "name game" with them. The pigeons were presented with 128 black-and-white images from 16 different categories: baby, bottle, cake, car, cracker, dog, duck, fish, flower, hat, key, pen, phone, plan, shoe and tree. The researchers associated icons on each image as well so that the pigeons can remember them.

The researchers showed the pigeons images of different dogs and placed two different icons below each. The pigeons were asked to peck on the correct icon associated with dogs. They were rewarded with pellets each time they chose the correct icon. The researchers repeated the experiment with the rest of the categories.

The experiment revealed that not only did the pigeons learn the task, they also applied them correctly in all categories.

The researchers concluded that the pigeons are much smarter than previously thought. The team has been studying animal intelligence for decades.

"Unlike prior attempts to teach words to primates, dogs, and parrots, we used neither elaborate shaping methods nor social cues," Ed Wasserman, study co-author and UI professor of psychology, said in a university news release. "And our pigeons were trained in all 16 categories simultaneously, a much closer analog of how children learn words and categories."

The results of the experiment showed similarities between pigeons' learning and how children learn words. The researchers believe that the method they used for the pigeon can be applied to other animals to learn more about animal cognition.

"Differences between humans and animals must indeed exist: many are already known. But, they may be outnumbered by similarities. Our research on categorization in pigeons suggests that those similarities may even extend to how children learn words," Wasserman said.

The study was published in the journal Cognition.