...This is one of those Threads which I begin, seeking opinion, not having any other Public (Internet) Forum upon which to write a Theory...
Birdsong is, of course, a marvellous thing to hear. My "Theory" is exactly as I say there. Birds 'walk or run' using the Air. We, as mostly Heel-Pressing Walking Humans (in this country), do not press the Air to move... but Birds, with Wings, often do so. I have seen lots and lots of 'Scientific' perspectives as to "why birds sing", and wanted to make this Perspective to the Public.
...When Your Foot or House is "dirty", then usually You clean it! Cleaning it is as if "asserting Your own identity" over everything else where You must stay/live... but Humans cannot hear the sounds which their Chemicals/brooms/vacuum-cleaners leave in the Air. Yet This is what Birds do, and hear, and feel, and Use... and so, in order to "clear their own Air for efficient Flight... they assert their own Frequencies for use.
This also explains sometimes why such as Starlings or Corvids make "car alarm" or "siren" noises... they can hear these and mimic them in order to blast their own version of them to clear the Air so that they can navigate despite such "noise pollution".
...In closing, I do not mind getting no replies... as I said, This is My only (safe) Forum and I wanted to see if anyone else understands this perspective. Thanks for reading if Anyone did it all the way through. (About a "socially trivial topic", too.)
Disambiguating Cynosure said:Humans cannot hear the sounds which their Chemicals/brooms/vacuum-cleaners leave in the Air.
...I am emphasizing that part. Also, I do not mind if no-one gets this Thread. See Y'all later.