New CT scans of the three completely preserved dodo skulls reveal that the extinct flightless bird possessed a forebrain proportioned similarly to modern pigeons and likely adapted to low-light foraging, challenging centuries of historical caricatures portraying it as unusually foolish.
Reconstructing the Dodo’s Skull with High-Resolution CT Scans
More than three centuries after its extinction on the island of Mauritius, the dodo remains a potent cultural icon of human-caused environmental loss. Lewis Carroll’s Alice in Wonderland helped popularise the image of a clumsy, foolish creature, while 18th-century Swedish naturalist Carl Linnaeus dubbed the species Dodus ineptus
due to its perceived lack of wit.
An international collaboration involving researchers across Canada, Australia, the United States, Europe, and the UK sought to test those historical assumptions.
Evaluating Avian Intelligence Against Modern Pigeons
As a member of the pigeon family, the dodo shares evolutionary lineage with birds renowned for their navigational capabilities and cognitive skills. When researchers compared the brain proportions of the dodo to living pigeons, they discovered that the forebrain—the region linked directly to memory and cognition—matched the relative proportions found in modern relatives.
Associate Professor Andrew Iwaniuk from the University of Lethbridge noted that the dodo featured an unusually domed skull, yet the brain center responsible for cognition measured exactly what scientists would predict for a bird of its size.
Sensory Adaptations and Nighttime Foraging Habits
While cognitive capacity matched modern relatives, the dodo’s sensory architecture revealed an unexpected twist. The optic lobes—the specific brain region handling early visual processing—proved unusually small when compared both to living pigeons and to its closest relative, the extinct Rodrigues solitaire.
Professor Vera Weisbecker of Flinders University explained that similarly reduced optic lobes typically appear in nocturnal or low-light specialists such as owls, kiwis, the New Zealand kakapo, and the Australian night parrot. This anatomical trait suggests the dodo’s vision was optimized for darker conditions.
“We suspected that dodos were better adapted to seeing in darker conditions. They had slightly larger eyes, but unusually small optic lobes, an area of the brain that processes light.”
Professor Vera Weisbecker, Flinders University
PhD student Sara Citron of the University of Lethbridge noted that this adaptation likely made the dodo active at dawn, dusk, or night-time, potentially functioning as the world’s only nocturnal pigeon.
Ecological Competition and Food Sources on Mauritius
Operating during cooler, darker hours offered a distinct survival advantage on Mauritius. The island once supported large populations of giant tortoises that fed on many of the identical fruits and plants consumed by the dodo.
By shifting foraging habits into twilight and nighttime hours, the dodo could access food sources with substantially reduced competition from local reptiles. Additionally, researchers observed that a relatively large olfactory brain region hinted at a strong sense of smell, though further comparative data across museum collections remains necessary to confirm the extent of that reliance.
Rethinking the Demise of a Trusting Island Species
The historical narrative surrounding the dodo’s rapid extinction within decades of human arrival often framed the bird’s cooperative passivity as proof of dim wits. Early sailors described capturing individuals and letting them cry out to attract others.
Researchers emphasize that this vulnerability stemmed from evolution on a predator-free island rather than intellectual deficiency. These gentle animals were possibly quite social. Like many island species, they were also used to a life without predators. They may simply have had no reason to learn fearful behaviour,
Citron explained, adding that calling the birds stupid for exhibiting natural naivety unfairly shifts blame for human-driven extinction onto the species itself.
