New CT scans of three dodo skulls reveal that the extinct bird possessed a normal-sized brain for its body weight and average cognitive abilities, challenging centuries-old stereotypes of avian stupidity. According to researchers at the University of Lethbridge and the Natural History Museum Denmark, the bird’s reputation as sluggish and easily caught originated from 17th-century sailors’ written impressions rather than empirical measurements.
How Researchers Scanned the Extinct Dodo’s Skull
The study, published on August 5 in the Zoological Journal of the Linnean Society and led from the University of Lethbridge in Canada, utilized computed tomography (CT) data from three dodo skulls. Researchers digitally reconstructed the endocast—a 3D model of the brain cavity—and compared the results against scans of 36 living species of pigeons, along with the dodo’s extinct relative, the Rodrigues solitaire from a neighboring island. Because bird brains sit tightly against the bone wall, the cavity shape accurately reflects the relative sizes of different brain regions, according to Store norske leksikon.
Rare Museum Specimens Unlock Avian Neurology
Only two complete dodo skulls exist globally: one housed at the Natural History Museum Denmark in Copenhagen, and another at the Oxford University Museum of Natural History. Researchers supplemented these with a third, less complete but well-preserved specimen from the Natural History Museum in London. Peter Andrew Hosner, associate professor and bird curator at the Natural History Museum Denmark, notes that while the dodo remains one of the world’s most recognizable extinct animals, scientists still know surprisingly little about its actual biology. Christy Anna Hipsley, a colleague at the same museum, explains that studying extinct fauna functions like detective work, relying entirely on skeletal remains to infer behavior.
Normal Cognition Dispels Historical Myths
Neurological analysis shows that the region of the dodo’s brain responsible for cognition was proportionally normal for a bird of that size. Andrew Iwaniuk of the University of Lethbridge states that no evidence supports the idea that the dodo was less intelligent than its relatives. The persistent myth stems entirely from the bird failing to flee when humans landed. On an island devoid of terrestrial predators, this behavior reflected a lack of experience rather than a lack of intelligence.
Unusual Visual Systems and Sensory Adaptations
The most striking anatomical discovery involves the visual system. According to the study, the optic lobes—the brain structures processing visual stimuli—were more than 3.5 times smaller relative to endocast size than those of the Nicobar pigeon, the dodo’s closest living relative. Vera Weisbecker of Flinders University points out that while the birds possessed slightly larger eyes, their optic lobes remained unusually diminutive. This combination of large eyes and small optic lobes typically appears in owls rather than diurnal pigeons, leading the research group to suggest the dodo may have extended its activity into the twilight hours.
Did you know?
An endocast is a digital or physical replica of the cranial cavity. Modern CT scanning allows researchers to create these models without damaging fragile historical artifacts, replacing older plaster and latex techniques.
Olfactory and Tactile Findings
Other sensory assessments yielded mixed results. One dodo specimen exhibited clearly enlarged olfactory bulbs measuring 3.44 percent of the endocast, whereas a second specimen showed just 1.36 percent, leading researchers to classify the olfactory findings as inconclusive. In contrast, the trigeminal nerve—which transmits sensory signals from the face—showed an enlarged ophthalmic branch. This adaptation aligns with a large upper beak likely used for tactile foraging, though scientists emphasize that definitive confirmation of sensory capabilities remains impossible without preserved soft brain tissue.
Frequently Asked Questions
Was the dodo actually stupid?
No. According to CT scans of surviving skull specimens, the dodo’s cognitive brain centers were entirely normal for a bird of its size. Its reputation for stupidity arose because it did not run away when humans came ashore on an island with no land-dwelling predators.
How many complete dodo skulls exist?
Only two complete dodo skulls exist on the planet: one at the Natural History Museum Denmark in Copenhagen and another at the Oxford University Museum of Natural History.
What did the CT scans reveal about the dodo’s vision?
Researchers discovered that the dodo’s optic lobes were over 3.5 times smaller relative to brain cavity size than those of its closest living relative, the Nicobar pigeon, suggesting unusual visual adaptations that may have extended into the twilight hours.
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