A study publishing in Proceedings of the National Academy of Sciences finds that olive baboons and Rhesus macaques, human preschoolers, and adults — including 79 Bolivian Tsimane' farmer-foragers without U.S.-style formal schooling — match abstract two-dimensional shapes using fundamentally the same cognitive strategy. Geometric intuition, the researchers argue, is part of the basic architecture of the primate mind, predating schools and culture.
The Research
Jessica Cantlon, a cognitive neuroscientist at Carnegie Mellon University's Department of Psychology and Neuroscience Institute and senior author of the study, led a team that tested multiple species on the same touchscreen matching game. Monkeys earned fruit snacks for participating. The task was deceptively hard: shapes carried no distinctive colors, sizes, or surface textures, so matches had to rely on geometric similarity alone.
"You'd get tripped up, too," Cantlon said. "That might seem easy, but it's actually pretty difficult, because there are no distinctive features among the objects."
The researchers compared olive baboons and Rhesus macaques with dozens of preschoolers (ages 3–6) at CMU's Children's School, 21 American adults, and 79 adults from Bolivia's indigenous Tsimane' community. Because the Tsimane' do not undergo the same formal schooling found in the United States, the design isolated raw developmental and evolutionary intuitions from academic training.
"That allowed us to sort of tease apart age and cultural experience," Cantlon explained, "because sometimes when you're trying to study something in children, it can be difficult to untangle whether their ability is developmental or something learned from education or experience."
Across every group, the team found clear continuity: monkeys, children, and adults evaluated abstract geometric relationships in fundamentally the same way. "What surprised us wasn't just that monkeys could do the task," Cantlon said. "It was that monkeys, children and adults seemed to think about geometric relationships in fundamentally the same way." Part of the data came through the Primate Portal at Seneca Park Zoo, an open-access touchscreen kiosk where free-ranging baboons volunteer for cognitive tasks while generating open data for K-12 STEM programs.
Why It Matters
Geometry is not something we build from scratch in a classroom. Formal education appears to elaborate on deep, biologically ancient foundations shared with other primates. For anyone curious about their own mind, that reframes what "math ability" is: less a talent you either have or lack, and more a set of intuitions that schooling sharpens. It also means spatial and geometric reasoning is worth practicing at any age, because the underlying machinery is already there.
What You Can Do
- Practice matching and mentally rotating shapes without relying on color or labels — the harder, feature-free version strengthens the same reasoning the study measured.
- Spend a few minutes on spatial puzzles or pattern-matching tasks daily rather than in one long session.
- Notice your own geometric intuitions when estimating distances, angles, or symmetry in everyday life; naming them makes the skill more deliberate.
Source: Neuroscience News
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