This is wild. Crows in this study could tell that recordings of people speaking Japanese (the language of the researchers) was different from recordings of people speaking Dutch. We can’t do that listening to birds. Unless we were a highly trained specialist, we couldn’t distinguish between mockingbird songs in one part of the country from mockingbird songs in another part of the country, though each song has a ‘dialect” that makes them mutually unintelligible. All the mockingbird would know is that another mockingbird is yelling at it. It has to learn to sing in the local dialect (meaning mockingbirds have learned cultures, actually.) But when a crow hears recordings of humans speaking different languages, it can tell that we are not speaking the same language, and it reacts to them differently. They were used to Japanese. They were wary of the recording in Dutch. What were they hearing? Japanese isn’t tonal like Chinese, so it’s not that the crows can tell that one is melodic and the other not. Can they detect the different phonemes (the vowel and consonant sounds) the languages use? Can they distinguish stresses, like what part of a sentence rises or drops? Can they detect the specific rhythms or sound patterns of grammar? How is it that a goddam bird can tell if a person is speaking Dutch or speaking Japanese while we with our enormous brains can’t tell if a recording of a mockingbird screaming at five in the morning is in Southern California Mockingbirdese or Danish Mockingbirdese? I can write about the concept of a crow distinguishing human languages, but damn if I can imagine what it is they actually hear in our human sounds.
Listening to these mockingbirds improv reminds me of a factoid I read today in Daniel Tammet’s Embracing the Wide Sky that in order for male songbirds to sing some of the incredibly complex songs which change constantly, up to one per cent of the neurons in their song center are replaced by new neurons every single day, which adds up pretty quickly. That’s what those mockingbird brains are doing, rebuilding themselves continuously. Not adding brain cells to what is there already, but replacing them. It’s as if in order to speak we had to replace 100% of the neurons in our language center every 100 days. That is, all the grammar we’ve hardwired into our brain is replaced by entirely new brain cells with all new intricately laced connections between them four times a year. It’s not quite that simple (some of the neurons in the mockingbird’s song center will be replaced more often than others and others are more permanent), but still, our grammar and vocabulary would completely and fundamentally change over a period of a hundred days. Not all at once, but a little everyday so that you’d be speaking a completely different language in April from what you were speaking on January 1. I’m writing this in English now and a hundred days from now I’d be writing this in Armenian, and next year in Sioux. Plus I’d wake you up at five in the morning screaming outside your window.
I could hear a pair of great horned owls calling to each other just now, first the female’s somewhat higher pitch, sort of like that of a mourning dove. Then the male’s deeper, louder response. They alternated like that for several minutes. Each call was five or six notes in a monotone, breathy and eerie, and by day would be buried under the cacophony of mockingbirds, but in the weird silence of our neighborhood tonight, like a country town and not just a couple miles from Hollywood and downtown, I could hear them plainly even though the windows are shut. I snuck outside to see if I could glimpse a silhouette, but nothing, just the haunting notes back and forth. Soon only the female called, the male having stolen away in silence. Then she too stopped, and there was almost complete silence but for the steady hum of traffic on the freeway in the distance.