How smart are birds? Smarter than cats? Smarter than snakes? Smarter than me? The birds around my house seem to have learned when and where I feed them and have even told some of their friends about the free lunch. So how does this rank on the smartometer?
-- B, San Diego
In the big brain weigh-in, birds are relative lightweights, I'm afraid. They have the highest brain-to-body weight ratio of any but the mammals, but of course birds' bodies are designed to be as light as possible, so that traditional measure may not say much. Most of their gray matter is devoted to vision and hearing, not analytical thinking. And if a snail pulls off what we see as a really clever stunt, we might be inclined to say it is "smart." Likewise, if your expectations of house sparrows are low, then certain behaviors might make them look like Nobel candidates.
Birds have innate systems of behaviors related to feeding, reproduction, safety, and social interaction. But through habituation, imitation, and trial and error, each bird refines these behaviors to suit its environment. And when food is the reward, many birds can appear to be very smart. Actually, they've just identified a location in their territory where there seems to be an abundance of food, so they return to it every day on their regular rounds of food gathering. And a few birds eating will attract other birds who want to share the chow. Stop feeding them, they'll go someplace else. Smart? Well....
But consider an anecdote reported in an ornithological journal about some house sparrows in Hamilton, New Zealand. The local bus station's sliding doors open automatically when an object passes through a light beam. The sparrows knew there were crumbs around the tables in the station's restaurant, and several of the learned that by hovering in the beam or by flying through it, the doors would open. Some sparrows even learned to perch on top of the light sensor and tilt their heads down to interrupt the beam. It's difficult to say how much they could generalize from this specific learning experience, but the bus station birds rank pretty high on the Matthew Alice smartometer.