Study Finds Bird Brains are More Neuron Dense Than Mammal Brains

Posted on June 20, 2016

A new study has found that brains of birds are more densely packed with neurons than the brains of mammals, including primate brains. Researchers found birds' forebrains contain as many neurons as are found in the forebrains of mid-sized primates.

Neurons in avian brans are smaller and more densely packed than in mammalian brains. Parrot and songbird brains contain about twice as many neurons as primate brains of the same mass and two to four times as many neurons as equivalent rodent brains.

Vanderbilt University neuroscientist Suzana Herculano-Houzel says in a statement, "In designing brains, nature has two parameters it can play with: the size and number of neurons and the distribution of neurons across different brain centers and in birds we find that nature has used both of them."

The researchers say the finding suggests the densely packed avian brains provide birds with a much higher "cognitive power" per pound than mammals.Studies have shown birds demonstrating intelligence and tool use. Scientists say parrots and crows can manufacture and use tools, use insight to solve problems, make inferences about cause-effect relationships, recognize themselves in a mirror and plan for future needs. The neuron dense bird brain could explain why some birds seem to be as smart as monkeys with larger brains.

Vanderbilt researcher Suzana Herculano-Houzel explains her bird brain research in this video. A research paper on the study can be found here in the journal, PNAS. Take a look: