The Nervous System in Birds

Birds, while commonplace and even boring to some, may actually be our greatest rivals in terms of nervous system efficiency.

The Scrub-Jay, a species of Corvid. From the Creagrus Website

Despite the strong senses of smell, taste, touch, and hearing that birds don, they are just as much or likely more reliant on visual cues than us. As a result, they have incredibly acute eyesight and typically have more detailed vision than humans.

The eye of a starling takes up about 15% of the weight of its head, whereas human eyes only take up about 1%. Most birds can adjust to light 2 times as quickly as a 20 year old person. They are also able to drastically change the lens shape to focus on different objects in quick succession. Most diurnal (opposite of nocturnal) birds can see as many if not more colors than humans. Their impeccable vision makes sense due to their lifestyle as tiny pilots. If they were not able to see the details of their environment and adjust swiftly, they would likely not be as aerially adept as we see them today.

Some birds can see UV light and other shades of colors that we don't see as vibrantly.

Like reptiles and amphibians, birds use a nictitating membrane to keep their eyes hydrated above water.

Graph of songbird and parrot neuron density in the brain compared to various mammals.

Diagram of brain region sizes in both birds and mammals.

Studies have shown that birds tend to have more dense brains than mammals, especially in a region called the pallium that deals with higher-level thinking. Even though they are much smaller than most primates, many reach the same level of cognitive ability. Corvids especially are known to be able to learn and problem-solve similarly to young children. These skills aid their hunting and foraging behaviors in the wild.