Understanding the Intelligence of Pigeons: Challenging Old Beliefs
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For a long time, many assumed that birds, especially pigeons, lacked intelligence. However, Professor Michael Colombo from the University of Otago, New Zealand, aims to alter this perception. Research indicates that pigeons can learn to count and recognize words comparably to monkeys. This capability is surprising given that birds do not possess a cortex, a brain region typically linked to intelligence in primates. Nevertheless, they can grasp and excel in complex tasks.
Birds often do not rank high on the list of intelligent animals. Instead, they are commonly viewed as simple-minded creatures, and terms like ‘birdbrain’ are frequently used as insults. This perspective is prevalent among both the public and the scientific community.
In the 1960s, a few researchers attempted to show that birds could perform tasks similar to monkeys, but their findings were often dismissed as mere tricks. The belief was that birds could only exhibit these abilities through training, while monkeys were recognized for their inherent skills.
During the 1980s and 1990s, the narrative began to shift, particularly with studies on scrub jays, a vibrant member of the corvid family. These birds demonstrated remarkable memory, perspective-taking, and future planning capabilities. Consequently, perceptions of bird intelligence began to change, elevating parrots and crows as ‘feathered apes,’ while pigeons remained overlooked.
“The similarity in performance between pigeons and baboons suggests that the ability to process written information is not exclusive to primates,” stated Colombo.
The turning point for pigeon research came in the 1990s, when groundbreaking experiments revealed their cognitive skills. For instance, Shigeru Watanabe’s lab at Keio University in Tokyo trained pigeons to critique art, discerning between works by Picasso and Monet.
Colombo and his team are now training pigeons to tackle challenging tasks, with the goal of comparing their performance to that of monkeys.
Can Birds Learn to Count and Read?
The first challenge presented to the pigeons involved counting. While humans have advanced numerical skills, these abilities are thought to derive from a fundamental number system present in various species.
Monkeys, for instance, have been shown to grasp this concept. Researchers Elisabeth Brannon and Herb Terrace from Columbia University taught monkeys to arrange images based on quantities. The monkeys quickly learned to arrange up to four items and could independently count beyond that.
To examine the mathematical capabilities of pigeons, Colombo’s team trained them similarly, beginning with one to three items before progressing to four through nine. To their surprise, pigeons matched the monkeys’ performance. “In terms of numerical skills, pigeons align closely with primates and can provide insights into the evolutionary pressures and brain structures essential for abstract numerical understanding,” the researchers noted.
The second challenge involved reading, a more intricate task. Children learning to read must connect letters to sounds and visually recognize words. While associating letters with sounds seems unique to humans, recent studies suggest that word recognition may stem from the ability to identify familiar objects.
For example, Jonathan Grainger and his team at Aix-Marseille University trained baboons to distinguish words from nonwords. Over several months, the monkeys learned over 300 words, demonstrating an ability to identify unfamiliar words.
Colombo’s research found that pigeons could similarly differentiate between words and nonwords, even recognizing new words they had never encountered before. This indicates that pigeons have developed an understanding of word structures.
“The performance of pigeons was comparable to that of baboons, indicating that the ability to process written information isn't limited to primates,” Colombo explained. “We showed that pigeons trained to differentiate words from nonwords recognized the characteristics that define words, applying this knowledge to previously unseen words.”
Colombo and his colleagues argue that there is no cognitive skill that monkeys display that pigeons cannot also exhibit. They assert that ranking one species as more intelligent than another is misguided. When controlling for factors like visual perception in monkeys and olfactory capabilities in rats, the performance of different species becomes indistinguishable.
As psychologist Euan Macphail from the University of York posited in the 1980s, Colombo believes there are no fundamental differences in intelligence among vertebrate species. This view faced initial skepticism, as recognizing the intelligence of pigeons—a species often dismissed as ‘winged rats’—is challenging for many. However, society is gradually beginning to acknowledge that intelligence manifests in various forms.
“It’s plausible that the structure of avian brains, due to their unique nuclear organization, may actually provide greater cognitive capacity than primate brains,” Colombo remarked.
The Remarkable Structure of the Avian Brain
These findings reveal that birds are far from unintelligent. It is essential to explore the origins of this misconception. Birds lack a cortex, often associated with advanced cognitive functions in mammals. Early studies concluded that without a cortex, birds lacked the capacity for higher-level thinking.
Yet, birds exhibit remarkable capabilities without one. Their neurons are clustered, known as nuclei, rather than layered as seen in mammalian brains. Intriguingly, this architecture allows birds to contain more neurons than similarly sized primates.
For instance, songbirds and parrots have twice the number of neurons compared to similarly sized primates. “Even pigeons, often stereotyped as lacking intelligence, possess the same neuron count as primates of a similar size due to their nuclear structure. The avian brain may actually hold more cognitive potential than its primate counterpart!” Colombo noted.
Intrigued by the pigeon brain, the research team is delving deeper into its unique nuclear architecture to uncover how it supports such extraordinary abilities. “Perhaps modern software built on primate brain architecture should consider the avian design instead,” Colombo mused.
What Next for Pigeon Research?
By investigating how the avian brain supports skills comparable to those of nonhuman primates, we can begin to discern what makes the human brain distinct. The team is pushing the boundaries of what pigeons can achieve, currently training them to play classic memory games involving matching cards and even tic-tac-toe. Given sufficient time, Colombo believes he could train a pigeon to solve a Rubik’s Cube!
References - Colombo M and Scarf D. (2020) Are there differences in “intelligence” between nonhuman species? The role of contextual variables. Front. Psychol, https://doi.org/10.3389/fpsyg.2020.02072 - Scarf D, Boy K, Reinert A, Devine J, Güntürkün O, and Colombo M. (2016) Orthographic processing in pigeons (Columba livia). PNAS, 113 (40) 11272–11276. https://doi.org/10.1073/pnas.1607870113 - Scarf D, Hayne H, Colombo M. (2011) Pigeons on par with primates in numerical competence. Science, 23;334(6063):1664. https://doi:10.1126/science.1213357
Research Objectives
Michael Colombo’s primary research focuses on the neural underpinnings of learning and memory, as well as the cognitive capabilities of animals.
Funding
Research funding was provided by a Royal Society of New Zealand Marsden grant 19-UOO-162 to MC.
Collaborators
- Dr. Damian Scarf
- Professor Onur Güntürkün
Bio
Professor Colombo earned his undergraduate degree in molecular biology and psychology from the University of Colorado, followed by a PhD from Rutgers University focusing on comparative animal cognition and neuroscience. After his PhD, he completed an NIH Postdoctoral Fellowship studying neural mechanisms of visual processing and memory in monkeys at Princeton University. He joined the Department of Psychology at the University of Otago in 1992.
Contact Department of Psychology University of Otago PO Box 56 Dunedin 9054 New Zealand
E: [email protected] T: +64–3–479–7626 W: https://www.otago.ac.nz/psychology/staff/mikecolombo.html