Bright bird brains are packed full of neurons: study
When it comes to brain cells, our feathered friends are remarkably good at making the most of their skull space. Amy Middleton reports.
How do birds manufacture and use tools, solve problems, understand words, recognise their own reflections and learn to predict human behaviours – despite having a brain the size of a walnut?
It turns out our clever feathered friends are packing more cells in their brains than we do, when calculated by weight, according to new research published in the Proceedings of the National Academy of Sciences.
Seweryn Olkowicz at Charles University in Prague and colleagues counted the cells in specific brain regions in 28 different birds species, focusing on parrots and corvids, the group that includes crows.
In these birds, higher numbers of neurons were concentrated towards the front of the brain where, in mammals, higher-order processing takes place.
And large parrots had as many neurons in their forebrains as monkeys, despite the vast difference in brain size.
"With their higher neuronal densities, songbird and parrot brains accommodate about twice as many neurons as primate brains of the same mass and two to four times more neurons than rodent brains of equivalent mass," the researchers write.
The researchers suggest birds may have developed these densely packed brains because they need to stay small and lightweight in order to fly.