re 'auditory fine structure', humans probably use this stuff too. check out 1970s work by smith etc on 'chimeric sounds', a study mixing low-frequency temporal envelope + high-frequency signal content from different speakers. humans apparently use one part for speech, the other for pitch + location.
sciam article hints at low harmonics mattering more to finches; some birds produce low harmonics via the 'pulse tone register', i.e. a mixing property of the dual syrinx. this is why birds sometimes sound like they've been run through an 8-bit encoder
This video[0] seems relevant on the topic of similarity between human speech and birdsong. I'm not nearly smart enough to conclude if that similarity means anything or is just a happy coincidence.
> One pivotal finding from such work is that birds perform surprisingly poorly on recognizing a melody shifted up or down in pitch.
I used to assume that the more fundamental mode of pitch perception would be intervals (the difference between two pitches) rather than absolute pitch perception. It is largely the other way around, however, which makes sense -- interval perception is based in pitch perception and comparison.
As someone who envies those with absolute pitch, it is still surprising to me that this mode of perception is biologically more fundamental.
As I understand it the inner ear performs a Fourier transform such that each location within in corresponds to a frequency detected in the sound.
That way, an interval or chord has a geometric shape plotted into the inner ear. The distance between detected points can be detected but not their absolute position.
It's probably a bit like how the eye detects objects: you see points of light that have set positions relative to each other (shape and size of the object), not the "absolute" positions in your field of view.
The absolute position is known to the brain; the mapping between locations on the basilar membrane and in the brain is called the tonotopic map. Why this information is only available to consciousness in some people is a mystery.
I would have liked to see a version of the test where they remove one of the symbols altogether, and see if the birds register it as different. There might be a gap of understanding as far as which songs the birds are reacting to. Pretty interesting study, though.
There are two main types of sound, I think. Alarm sounds and social sounds.
Alarm sounds indicate the presence of a predator or danger, and tend not to give away the position of the source. Think a continuous tone, it's hard to pinpoint the location by sound.
"Social" noises on the other hand have a more staccato character and allow the hearer to pinpoint the location of the source.
I live with a bird (parrot). There are alarm sounds, social sounds, and mood sounds.
The alarm sounds are very very loud. You can pinpoint them from the other side of the house, possibly the neighborhood. Any potential confusion about direction would come solely from the immense loudness and sound echoing off walls. The bird typically flies away from the location it made those sounds. In a smaller room, the sound itself can be incapacitating. It overwhelms your senses. I'm told in the wild those sounds can be heard up to a mile away.
The social sounds come in different forms. Everything from loud flock calls that were originally designed for isolated members of the flock to find each other in a dense jungle with no line of sight. These too can travel up to a mile in the wild, but they feel more pleasant to the ear. You can tell the bird is beckoning you and just making sure you're still within earshot. When you're close-by, the social sounds can be quiet womps, almost like a conversation. Especially funny when you're on a zoom call and the bird thinks you're talking to them. Sometimes they're loud sharp beeps. I don't know what those mean but they can make your ears ring.
Mood sounds are usually of the quiet wompy kind. Like the bird is entertaining itself, or being cozy and muttering to itself under its breath. Sometimes the bird gets excited and lets out a sharp scream ... this could be social of the "Hey look what I got!" variety.
When I was a teenager I kept birds, though not parrots and it's been a long while. (I don't think I could keep caged birds anymore, but that's a different can of worms).
What you say matches my experience! It's really funny when you hear a bird "muttering" to itself, they almost seem human. Also when it gets excited and lets out a loud beep!
> I don't think I could keep caged birds anymore, but that's a different can of worms
This one lives more like a dog or a cat. Flying around the apartment as he pleases. The only time he goes in his cage is when it’s safer for him (or us, parrots bite when displeased).
Funnily he gets very angry when his cage door is closed and he’s outside … even though he never goes in there. But he might … he does ask to be caged when it’s bed time. It’s quite endearing.
When I had birds that's precisely what they did. Birds typically like to be in the highest comfortable place in a room for instinctual reasons. In my apartments at the time, that meant the tops of virtually any open doors. (They also liked company so they'd generally follow me from room to room and sit on top of doors along the way.) You really don't want ceiling fans...
So, yeah. I made sure there was generally something on the floor below them. But the sides of the doors would need to be cleaned fairly regularly. I had cockatiels, and you couldn't "potty train" them.
Birds also like to chew things sometimes, so you needed to keep a close eye on them or realize your damage deposit was going to take a hit later.
The bird we have is a super social species so his favorite spot is on your shoulder or inside your shirt. He flies away to poop. We were able to potty train him so he doesn’t poop on us and generally avoids couches, beds, and such.
He does poop everywhere else though. Usually in a few common spots. Fortunately it doesn’t smell and we just wipe it with a paper towel.
Training him to poop in sinks had limited success. We aren’t patient enough.
As for windows, we keep screens on them. He probably wouldn’t fly away on purpose but when a bird gets spooked you never know.
Seems to be a conure trait. I have a green cheek that's also like that. Won't poop on us (except by accident or out of spite), but our budgie really doesn't care where he poops.
What's fascinating is that the warning calls of other bird species seem to be understood by Parrots, too.
I have a Rainbow Lorikeet and a Rose-Breasted Cockatoo that moved in along with the wife after we married - The Lorikeet is extremely animated, and the Cockatoo (a rescue) extremely timid.
The Lorikeet has learnt to mimic the warning calls of local Sulphur-Crested Cockatoos, Noisy Minors, Common Mynahs.
Occasionally, in the dead of night, the Lorikeet would make little satisfaction chirps while he's preening himself. He'd also recall all the sounds he's learnt to date, sometimes including warning calls of other birds - which sends the poor Cockatoo into a frenzy each time.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2268248/
sciam article hints at low harmonics mattering more to finches; some birds produce low harmonics via the 'pulse tone register', i.e. a mixing property of the dual syrinx. this is why birds sometimes sound like they've been run through an 8-bit encoder