When someone does something stupid or behaves in a scatter-brained way, we may jeeringly, scornfully, call that person a ‘birdbrain’! But wait a minute: is that epithet really accurate or fitting? Consider some of the amazing things that avian brains accomplish!
Chickadees, nuthatches, and corvids (jays, crows, ravens) cache food and can remember hundreds and thousands of cache locations for weeks and months. Clark’s Nutcrackers (another corvid) spread their hidden stores of pine seeds over many square miles and can retrieve almost all of them, even after several months. That’s a lot better than what many humans could do, even with practice.
Crows of various species have shown considerable ability to figure out problems that require insight. New Caledonian crows invent new ways of extracting a food item, by using a sequence of tools in the appropriate order. They can do this without practice, sometimes even inventing tools. For instance, one of these crows figured out how to use a little hook to extract a tiny food basket from inside a container, and when such a hook was not provided by the experimenter, the crow made one from a straight piece of wire. European rooks invent tools too and use them in novel situations; a rook quickly figured out that it could raise the water level in a beaker by dropping stones into the water, thus raising a floating food item up where the crow could get it. Crows in Japan drop nuts in front of traffic, letting the vehicles crack them open; if the vehicles miss a crow’s prize item, the crow may pick it up and drop it in the traffic lane again. This is a relative new trick, just developed a couple of decades ago, and it shows that the birds are capable of insight.
Some birds (parrots) are capable of reasoning by analogy. For example if items A and B are different from each other, but C and D are identical, these birds learn the concept of ‘different’ and ‘same’ and can apply it to a novel situation, recognizing that items W and X are different but Y and Z are the same. Thus they show some ability for abstract reasoning. I know some otherwise apparently normal humans that would have trouble doing that!
Many birds are capable of observational learning—watching another bird do something and copying what they see–and some birds (parrots, some songbirds) can copy sounds or songs too. Many mammals cannot do this. Certain birds go on learning new songs all their lives: canaries learn new songs (and grow new neurons to do it) every year, replacing the old neurons and songs, while mockingbirds and parrots can go on increasing their repertoires throughout their lives.
The tiny brain of a hummingbird (smaller than a pea) is capable of guiding the bird on extended migrations, up and down the Pacific Rim in the case of our rufous hummer and over the Gulf of Mexico in the case of the ruby-throated hummer. No mean feat!
All that is not to imply that bird brains are like human brains. Like our brains, bird brains do have right and left sides, which function differently. But birds have considerably bigger brains, relative to body size, than humans do. As in all vertebrates, bird brains are divided into three parts (fore, mid, and hind) and in both birds and mammals, it is the forebrain that is specialized for ‘smarts’. In birds, however, it is the so-called hyperstriatum (an inner part of the forebrain) that provides what we call intelligence, whereas in mammals it is the cerebral cortex (the outer part of the forebrain). (But contrary to what you might read on Wikipedia, bird brains are NOT located in the thorax!)
So, the bottom line here is that bird brains are really not to be scoffed at. Perhaps they should even be admired for some of their amazing accomplishments! Humans have had a hard time learning that other animals have talents, skills, wit, and emotions, worthy of respect, even though Darwin paved the way over a hundred and fifty years ago. We can be very slow learners, despite our much-vaunted gray cells. Perhaps there is a lesson there!