CT scans of the brain cases of a dodo and its close relative the Rodrigues solitaire, which is also extinct, reveal that – relative to their large bodies – their brains were on a par with other members of the pigeon family.
“I would imagine that their extinction had more to do with them being three-foot [0.9m] flightless birds, trapped on a small island hunted by hungry sailors, than any measure of intelligence or learning,” said Eugenia Gold of the American Museum of Natural History, who led the study.
The scans also identified unusually large olfactory bulbs – the region of the brain that processes smell.
“Flight navigation relies on visually inspecting the upcoming environment. This could override the expansion of the olfactory bulbs and keep them small,” said Gold.
“However, since the dodo and solitaire could not fly, the birds’ brains may have emphasised smell instead.”